/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.appunite.list;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.support.v4.view.KeyEventCompat;
import android.util.AttributeSet;
import android.util.SparseBooleanArray;
import android.view.FocusFinder;
import android.view.KeyEvent;
import android.view.SoundEffectConstants;
import android.view.View;
import android.view.ViewDebug;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityNodeInfo;
import android.widget.ArrayAdapter;
import android.widget.Checkable;
import android.widget.ListAdapter;
import android.widget.RemoteViews.RemoteView;
import java.util.ArrayList;
/*
* Implementation Notes:
*
* Some terminology:
*
* index - index of the items that are currently visible
* position - index of the items in the cursor
*/
/**
* A view that shows items in a vertically scrolling list. The items
* come from the {@link android.widget.ListAdapter} associated with this view.
*
* <p>See the <a href="{@docRoot}guide/topics/ui/layout/listview.html">List View</a>
* guide.</p>
*
* @attr ref android.R.styleable#ListView_entries
* @attr ref android.R.styleable#ListView_divider
* @attr ref android.R.styleable#ListView_dividerHeight
* @attr ref android.R.styleable#ListView_headerDividersEnabled
* @attr ref android.R.styleable#ListView_footerDividersEnabled
*/
@RemoteView
public class HorizontalListView extends AbsHorizontalListView {
/**
* Used to indicate a no preference for a position type.
*/
static final int NO_POSITION = -1;
/**
* When arrow scrolling, ListView will never scroll more than this factor
* times the width of the list.
*/
private static final float MAX_SCROLL_FACTOR = 0.33f;
/**
* When arrow scrolling, need a certain amount of pixels to preview next
* items. This is usually the fading edge, but if that is small enough,
* we want to make sure we preview at least this many pixels.
*/
private static final int MIN_SCROLL_PREVIEW_PIXELS = 2;
private ArrayList<ListView.FixedViewInfo> mHeaderViewInfos = new ArrayList<ListView.FixedViewInfo>();
private ArrayList<ListView.FixedViewInfo> mFooterViewInfos = new ArrayList<ListView.FixedViewInfo>();
Drawable mDivider;
int mDividerWidth;
Drawable mOverScrollHeader;
Drawable mOverScrollFooter;
private boolean mIsCacheColorOpaque;
private boolean mDividerIsOpaque;
private boolean mHeaderDividersEnabled;
private boolean mFooterDividersEnabled;
private boolean mAreAllItemsSelectable = true;
private boolean mItemsCanFocus = false;
// used for temporary calculations.
private final Rect mTempRect = new Rect();
private Paint mDividerPaint;
// the single allocated result per list view; kinda cheesey but avoids
// allocating these thingies too often.
private final ArrowScrollFocusResult mArrowScrollFocusResult = new ArrowScrollFocusResult();
// Keeps focused children visible through resizes
private FocusSelector mFocusSelector;
public HorizontalListView(Context context) {
this(context, null);
}
public HorizontalListView(Context context, AttributeSet attrs) {
this(context, attrs, R.attr.listViewStyle);
}
public HorizontalListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
TypedArray a = context.obtainStyledAttributes(attrs,
R.styleable.ListView, defStyle, 0);
CharSequence[] entries = a.getTextArray(
R.styleable.ListView_android_entries);
if (entries != null) {
setAdapter(new ArrayAdapter<CharSequence>(context,
android.R.layout.simple_list_item_1, entries));
}
final Drawable d = a.getDrawable(R.styleable.ListView_android_divider);
if (d != null) {
// If a divider is specified use its intrinsic width for divider width
setDivider(d);
}
final Drawable osHeader = a.getDrawable(
R.styleable.ListView_overScrollHeader);
if (osHeader != null) {
setOverscrollHeader(osHeader);
}
final Drawable osFooter = a.getDrawable(
R.styleable.ListView_overScrollFooter);
if (osFooter != null) {
setOverscrollFooter(osFooter);
}
// Use the width specified, zero being the default
final int dividerHeight = a.getDimensionPixelSize(
R.styleable.ListView_android_dividerHeight, 0);
if (dividerHeight != 0) {
setDividerWidth(dividerHeight);
}
mHeaderDividersEnabled = a.getBoolean(R.styleable.ListView_headerDividersEnabled, true);
mFooterDividersEnabled = a.getBoolean(R.styleable.ListView_footerDividersEnabled, true);
a.recycle();
}
/**
* @return The maximum amount a list view will scroll in response to
* an arrow event.
*/
public int getMaxScrollAmount() {
return (int) (MAX_SCROLL_FACTOR * (getRight() - getLeft()));
}
/**
* Make sure views are touching the top or bottom edge, as appropriate for
* our gravity
*/
private void adjustViewsLeftOrRight() {
final int childCount = getChildCount();
int delta;
if (childCount > 0) {
View child;
if (!mStackFromRight) {
// Uh-oh -- we came up short. Slide all views up to make them
// align with the top
child = getChildAt(0);
delta = child.getLeft() - mListPadding.left;
if (mFirstPosition != 0) {
// It's OK to have some space above the first item if it is
// part of the vertical spacing
delta -= mDividerWidth;
}
if (delta < 0) {
// We only are looking to see if we are too low, not too high
delta = 0;
}
} else {
// we are too high, slide all views down to align with bottom
child = getChildAt(childCount - 1);
delta = child.getRight() - (getWidth() - mListPadding.right);
if (mFirstPosition + childCount < mItemCount) {
// It's OK to have some space below the last item if it is
// part of the vertical spacing
delta += mDividerWidth;
}
if (delta > 0) {
delta = 0;
}
}
if (delta != 0) {
offsetChildrenLeftAndRightUnhide(-delta);
}
}
}
/**
* Add a fixed view to appear at the top of the list. If addHeaderView is
* called more than once, the views will appear in the order they were
* added. Views added using this call can take focus if they want.
* <p>
* NOTE: Call this before calling setAdapter. This is so ListView can wrap
* the supplied cursor with one that will also account for header and footer
* views.
*
* @param v The view to add.
* @param data Data to associate with this view
* @param isSelectable whether the item is selectable
*/
public void addHeaderView(View v, Object data, boolean isSelectable) {
if (mAdapter != null && ! (mAdapter instanceof HeaderViewListAdapter)) {
throw new IllegalStateException(
"Cannot add header view to list -- setAdapter has already been called.");
}
ListView.FixedViewInfo info = new ListView.FixedViewInfo();
info.view = v;
info.data = data;
info.isSelectable = isSelectable;
mHeaderViewInfos.add(info);
// in the case of re-adding a header view, or adding one later on,
// we need to notify the observer
if (mAdapter != null && mDataSetObserver != null) {
mDataSetObserver.onChanged();
}
}
/**
* Add a fixed view to appear at the top of the list. If addHeaderView is
* called more than once, the views will appear in the order they were
* added. Views added using this call can take focus if they want.
* <p>
* NOTE: Call this before calling setAdapter. This is so ListView can wrap
* the supplied cursor with one that will also account for header and footer
* views.
*
* @param v The view to add.
*/
public void addHeaderView(View v) {
addHeaderView(v, null, true);
}
@Override
public int getHeaderViewsCount() {
return mHeaderViewInfos.size();
}
/**
* Removes a previously-added header view.
*
* @param v The view to remove
* @return true if the view was removed, false if the view was not a header
* view
*/
public boolean removeHeaderView(View v) {
if (mHeaderViewInfos.size() > 0) {
boolean result = false;
if (mAdapter != null && ((HeaderViewListAdapter) mAdapter).removeHeader(v)) {
if (mDataSetObserver != null) {
mDataSetObserver.onChanged();
}
result = true;
}
removeFixedViewInfo(v, mHeaderViewInfos);
return result;
}
return false;
}
private void removeFixedViewInfo(View v, ArrayList<ListView.FixedViewInfo> where) {
int len = where.size();
for (int i = 0; i < len; ++i) {
ListView.FixedViewInfo info = where.get(i);
if (info.view == v) {
where.remove(i);
break;
}
}
}
/**
* Add a fixed view to appear at the bottom of the list. If addFooterView is
* called more than once, the views will appear in the order they were
* added. Views added using this call can take focus if they want.
* <p>
* NOTE: Call this before calling setAdapter. This is so ListView can wrap
* the supplied cursor with one that will also account for header and footer
* views.
*
* @param v The view to add.
* @param data Data to associate with this view
* @param isSelectable true if the footer view can be selected
*/
public void addFooterView(View v, Object data, boolean isSelectable) {
// NOTE: do not enforce the adapter being null here, since unlike in
// addHeaderView, it was never enforced here, and so existing apps are
// relying on being able to add a footer and then calling setAdapter to
// force creation of the HeaderViewListAdapter wrapper
ListView.FixedViewInfo info = new ListView.FixedViewInfo();
info.view = v;
info.data = data;
info.isSelectable = isSelectable;
mFooterViewInfos.add(info);
// in the case of re-adding a footer view, or adding one later on,
// we need to notify the observer
if (mAdapter != null && mDataSetObserver != null) {
mDataSetObserver.onChanged();
}
}
/**
* Add a fixed view to appear at the bottom of the list. If addFooterView is called more
* than once, the views will appear in the order they were added. Views added using
* this call can take focus if they want.
* <p>NOTE: Call this before calling setAdapter. This is so ListView can wrap the supplied
* cursor with one that will also account for header and footer views.
*
*
* @param v The view to add.
*/
public void addFooterView(View v) {
addFooterView(v, null, true);
}
@Override
public int getFooterViewsCount() {
return mFooterViewInfos.size();
}
/**
* Removes a previously-added footer view.
*
* @param v The view to remove
* @return
* true if the view was removed, false if the view was not a footer view
*/
public boolean removeFooterView(View v) {
if (mFooterViewInfos.size() > 0) {
boolean result = false;
if (mAdapter != null && ((HeaderViewListAdapter) mAdapter).removeFooter(v)) {
if (mDataSetObserver != null) {
mDataSetObserver.onChanged();
}
result = true;
}
removeFixedViewInfo(v, mFooterViewInfos);
return result;
}
return false;
}
/**
* Returns the adapter currently in use in this ListView. The returned adapter
* might not be the same adapter passed to {@link #setAdapter(android.widget.ListAdapter)} but
* might be a {@link android.widget.WrapperListAdapter}.
*
* @return The adapter currently used to display data in this ListView.
*
* @see #setAdapter(android.widget.ListAdapter)
*/
@Override
public ListAdapter getAdapter() {
return mAdapter;
}
/**
* Sets the data behind this ListView.
*
* The adapter passed to this method may be wrapped by a {@link android.widget.WrapperListAdapter},
* depending on the ListView features currently in use. For instance, adding
* headers and/or footers will cause the adapter to be wrapped.
*
* @param adapter The ListAdapter which is responsible for maintaining the
* data backing this list and for producing a view to represent an
* item in that data set.
*
* @see #getAdapter()
*/
@Override
public void setAdapter(ListAdapter adapter) {
if (mAdapter != null && mDataSetObserver != null) {
mAdapter.unregisterDataSetObserver(mDataSetObserver);
}
resetList();
mRecycler.clear();
if (mHeaderViewInfos.size() > 0|| mFooterViewInfos.size() > 0) {
mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, adapter);
} else {
mAdapter = adapter;
}
mOldSelectedPosition = INVALID_POSITION;
mOldSelectedColId = INVALID_COL_ID;
// AbsListView#setAdapter will update choice mode states.
super.setAdapter(adapter);
if (mAdapter != null) {
mAreAllItemsSelectable = mAdapter.areAllItemsEnabled();
mOldItemCount = mItemCount;
mItemCount = mAdapter.getCount();
checkFocus();
mDataSetObserver = new AdapterDataSetObserver();
mAdapter.registerDataSetObserver(mDataSetObserver);
mRecycler.setViewTypeCount(mAdapter.getViewTypeCount());
int position;
if (mStackFromRight) {
position = lookForSelectablePosition(mItemCount - 1, false);
} else {
position = lookForSelectablePosition(0, true);
}
setSelectedPositionInt(position);
setNextSelectedPositionInt(position);
if (mItemCount == 0) {
// Nothing selected
checkSelectionChanged();
}
} else {
mAreAllItemsSelectable = true;
checkFocus();
// Nothing selected
checkSelectionChanged();
}
requestLayout();
}
/**
* The list is empty. Clear everything out.
*/
@Override
void resetList() {
// The parent's resetList() will remove all views from the layout so we need to
// cleanup the state of our footers and headers
clearRecycledState(mHeaderViewInfos);
clearRecycledState(mFooterViewInfos);
super.resetList();
mLayoutMode = LAYOUT_NORMAL;
}
private void clearRecycledState(ArrayList<ListView.FixedViewInfo> infos) {
if (infos != null) {
final int count = infos.size();
for (int i = 0; i < count; i++) {
final View child = infos.get(i).view;
final LayoutParams p = (LayoutParams) child.getLayoutParams();
if (p != null) {
p.recycledHeaderFooter = false;
}
}
}
}
/**
* @return Whether the list needs to show the top fading edge
*/
private boolean showingLeftFadingEdge() {
final int listLeft = getScrollX() + mListPadding.left;
return (mFirstPosition > 0) || (getChildAt(0).getLeft() > listLeft);
}
/**
* @return Whether the list needs to show the bottom fading edge
*/
private boolean showingRightFadingEdge() {
final int childCount = getChildCount();
final int bottomOfRightChild = getChildAt(childCount - 1).getRight();
final int lastVisiblePosition = mFirstPosition + childCount - 1;
final int listRight = getScrollX() + getWidth() - mListPadding.right;
return (lastVisiblePosition < mItemCount - 1)
|| (bottomOfRightChild < listRight);
}
@Override
public boolean requestChildRectangleOnScreen(View child, Rect rect, boolean immediate) {
int rectTopWithinChild = rect.top;
// offset so rect is in coordinates of the this view
rect.offset(child.getLeft(), child.getTop());
rect.offset(-child.getScrollX(), -child.getScrollY());
final int width = getWidth();
int listUnfadedLeft = getScrollX();
int listUnfadedRight = listUnfadedLeft + width;
final int fadingEdge = getHorizontalFadingEdgeLength();
if (showingLeftFadingEdge()) {
// leave room for top fading edge as long as rect isn't at very top
if ((mSelectedPosition > 0) || (rectTopWithinChild > fadingEdge)) {
listUnfadedLeft += fadingEdge;
}
}
int childCount = getChildCount();
int rightOfRightChild = getChildAt(childCount - 1).getRight();
if (showingRightFadingEdge()) {
// leave room for bottom fading edge as long as rect isn't at very bottom
if ((mSelectedPosition < mItemCount - 1)
|| (rect.bottom < (rightOfRightChild - fadingEdge))) {
listUnfadedRight -= fadingEdge;
}
}
int scrollXDelta = 0;
if (rect.right > listUnfadedRight && rect.left > listUnfadedLeft) {
// need to MOVE DOWN to get it in view: move down just enough so
// that the entire rectangle is in view (or at least the first
// screen size chunk).
if (rect.width() > width) {
// just enough to get screen size chunk on
scrollXDelta += (rect.left - listUnfadedLeft);
} else {
// get entire rect at bottom of screen
scrollXDelta += (rect.right - listUnfadedRight);
}
// make sure we aren't scrolling beyond the end of our children
int distanceToRight = rightOfRightChild - listUnfadedRight;
scrollXDelta = Math.min(scrollXDelta, distanceToRight);
} else if (rect.left < listUnfadedLeft && rect.right < listUnfadedRight) {
// need to MOVE UP to get it in view: move up just enough so that
// entire rectangle is in view (or at least the first screen
// size chunk of it).
if (rect.width() > width) {
// screen size chunk
scrollXDelta -= (listUnfadedRight - rect.right);
} else {
// entire rect at top
scrollXDelta -= (listUnfadedLeft - rect.left);
}
// make sure we aren't scrolling any further than the top our children
int left = getChildAt(0).getLeft();
int deltaToTop = left - listUnfadedLeft;
scrollXDelta = Math.max(scrollXDelta, deltaToTop);
}
final boolean scroll = scrollXDelta != 0;
if (scroll) {
scrollListItemsBy(-scrollXDelta);
positionSelector(INVALID_POSITION, child);
mSelectedLeft = child.getLeft();
invalidate();
}
return scroll;
}
/**
* {@inheritDoc}
*/
@Override
void fillGap(boolean toRight) {
final int count = getChildCount();
if (toRight) {
int paddingLeft = 0;
if (mClipToPadding) {
paddingLeft = getListPaddingLeft();
}
final int startOffset = count > 0 ? getChildAt(count - 1).getRight() + mDividerWidth :
paddingLeft;
fillRight(mFirstPosition + count, startOffset);
correctTooHigh(getChildCount());
} else {
int paddingRight = 0;
if (mClipToPadding) {
paddingRight = getListPaddingRight();
}
final int startOffset = count > 0 ? getChildAt(0).getLeft() - mDividerWidth :
getWidth() - paddingRight;
fillLeft(mFirstPosition - 1, startOffset);
correctTooLow(getChildCount());
}
}
/**
* Fills the list from pos down to the end of the list view.
*
* @param pos The first position to put in the list
*
* @param nextLeft The location where the top of the item associated with pos
* should be drawn
*
* @return The view that is currently selected, if it happens to be in the
* range that we draw.
*/
private View fillRight(int pos, int nextLeft) {
View selectedView = null;
int end = (getRight() - getLeft());
if (mClipToPadding) {
end -= mListPadding.right;
}
while (nextLeft < end && pos < mItemCount) {
// is this the selected item?
boolean selected = pos == mSelectedPosition;
View child = makeAndAddView(pos, nextLeft, true, mListPadding.top, selected);
nextLeft = child.getRight() + mDividerWidth;
if (selected) {
selectedView = child;
}
pos++;
}
// FIXME removed bacause we do not need RemoteViews (j.m.)
// setVisibleRangeHint(mFirstPosition, mFirstPosition + getChildCount() - 1);
return selectedView;
}
/**
* Fills the list from pos up to the top of the list view.
*
* @param pos The first position to put in the list
*
* @param nextRight The location where the bottom of the item associated
* with pos should be drawn
*
* @return The view that is currently selected
*/
private View fillLeft(int pos, int nextRight) {
View selectedView = null;
int end = 0;
if (mClipToPadding) {
end = mListPadding.left;
}
while (nextRight > end && pos >= 0) {
// is this the selected item?
boolean selected = pos == mSelectedPosition;
View child = makeAndAddView(pos, nextRight, false, mListPadding.top, selected);
nextRight = child.getLeft() - mDividerWidth;
if (selected) {
selectedView = child;
}
pos--;
}
mFirstPosition = pos + 1;
// FIXME removed bacause we do not need RemoteViews (j.m.)
// setVisibleRangeHint(mFirstPosition, mFirstPosition + getChildCount() - 1);
return selectedView;
}
/**
* Fills the list from top to bottom, starting with mFirstPosition
*
* @param nextLeft The location where the top of the first item should be
* drawn
*
* @return The view that is currently selected
*/
private View fillFromLeft(int nextLeft) {
mFirstPosition = Math.min(mFirstPosition, mSelectedPosition);
mFirstPosition = Math.min(mFirstPosition, mItemCount - 1);
if (mFirstPosition < 0) {
mFirstPosition = 0;
}
return fillRight(mFirstPosition, nextLeft);
}
/**
* Put mSelectedPosition in the middle of the screen and then build up and
* down from there. This method forces mSelectedPosition to the center.
*
* @param childrenLeft Top of the area in which children can be drawn, as
* measured in pixels
* @param childrenRight Bottom of the area in which children can be drawn,
* as measured in pixels
* @return Currently selected view
*/
private View fillFromMiddle(int childrenLeft, int childrenRight) {
int width = childrenRight - childrenLeft;
int position = reconcileSelectedPosition();
View sel = makeAndAddView(position, childrenLeft, true,
mListPadding.top, true);
mFirstPosition = position;
int selWidth = sel.getMeasuredWidth();
if (selWidth <= width) {
sel.offsetLeftAndRight((width - selWidth) / 2);
}
fillToLeftAndRight(sel, position);
if (!mStackFromRight) {
correctTooHigh(getChildCount());
} else {
correctTooLow(getChildCount());
}
return sel;
}
/**
* Once the selected view as been placed, fill up the visible area above and
* below it.
*
* @param sel The selected view
* @param position The position corresponding to sel
*/
private void fillToLeftAndRight(View sel, int position) {
final int dividerWidth = mDividerWidth;
if (!mStackFromRight) {
fillLeft(position - 1, sel.getLeft() - dividerWidth);
adjustViewsLeftOrRight();
fillRight(position + 1, sel.getRight() + dividerWidth);
} else {
fillRight(position + 1, sel.getRight() + dividerWidth);
adjustViewsLeftOrRight();
fillLeft(position - 1, sel.getLeft() - dividerWidth);
}
}
/**
* Fills the grid based on positioning the new selection at a specific
* location. The selection may be moved so that it does not intersect the
* faded edges. The grid is then filled upwards and downwards from there.
*
* @param selectedLeft Where the selected item should be
* @param childrenLeft Where to start drawing children
* @param childrenRight Last pixel where children can be drawn
* @return The view that currently has selection
*/
private View fillFromSelection(int selectedLeft, int childrenLeft, int childrenRight) {
int fadingEdgeLength = getHorizontalFadingEdgeLength();
final int selectedPosition = mSelectedPosition;
View sel;
final int leftSelectionPixel = getLeftSelectionPixel(childrenLeft, fadingEdgeLength,
selectedPosition);
final int rightSelectionPixel = getRightSelectionPixel(childrenRight, fadingEdgeLength,
selectedPosition);
sel = makeAndAddView(selectedPosition, selectedLeft, true, mListPadding.top, true);
// Some of the newly selected item extends below the bottom of the list
if (sel.getRight() > rightSelectionPixel) {
// Find space available above the selection into which we can scroll
// upwards
final int spaceAbove = sel.getLeft() - leftSelectionPixel;
// Find space required to bring the bottom of the selected item
// fully into view
final int spaceBelow = sel.getRight() - rightSelectionPixel;
final int offset = Math.min(spaceAbove, spaceBelow);
// Now offset the selected item to get it into view
sel.offsetLeftAndRight(-offset);
} else if (sel.getLeft() < leftSelectionPixel) {
// Find space required to bring the top of the selected item fully
// into view
final int spaceAbove = leftSelectionPixel - sel.getLeft();
// Find space available below the selection into which we can scroll
// downwards
final int spaceBelow = rightSelectionPixel - sel.getRight();
final int offset = Math.min(spaceAbove, spaceBelow);
// Offset the selected item to get it into view
sel.offsetLeftAndRight(offset);
}
// Fill in views above and below
fillToLeftAndRight(sel, selectedPosition);
if (!mStackFromRight) {
correctTooHigh(getChildCount());
} else {
correctTooLow(getChildCount());
}
return sel;
}
/**
* Calculate the bottom-most pixel we can draw the selection into
*
* @param childrenRight Bottom pixel were children can be drawn
* @param fadingEdgeLength Length of the fading edge in pixels, if present
* @param selectedPosition The position that will be selected
* @return The bottom-most pixel we can draw the selection into
*/
private int getRightSelectionPixel(int childrenRight, int fadingEdgeLength,
int selectedPosition) {
int rightSelectionPixel = childrenRight;
if (selectedPosition != mItemCount - 1) {
rightSelectionPixel -= fadingEdgeLength;
}
return rightSelectionPixel;
}
/**
* Calculate the top-most pixel we can draw the selection into
*
* @param childrenLeft Top pixel were children can be drawn
* @param fadingEdgeLength Length of the fading edge in pixels, if present
* @param selectedPosition The position that will be selected
* @return The top-most pixel we can draw the selection into
*/
private int getLeftSelectionPixel(int childrenLeft, int fadingEdgeLength, int selectedPosition) {
// first pixel we can draw the selection into
int leftSelectionPixel = childrenLeft;
if (selectedPosition > 0) {
leftSelectionPixel += fadingEdgeLength;
}
return leftSelectionPixel;
}
/**
* Smoothly scroll to the specified adapter position. The view will
* scroll such that the indicated position is displayed.
* @param position Scroll to this adapter position.
*/
//@android.view.RemotableViewMethod
public void smoothScrollToPosition(int position) {
super.smoothScrollToPosition(position);
}
/**
* Smoothly scroll to the specified adapter position offset. The view will
* scroll such that the indicated position is displayed.
* @param offset The amount to offset from the adapter position to scroll to.
*/
//@android.view.RemotableViewMethod
public void smoothScrollByOffset(int offset) {
super.smoothScrollByOffset(offset);
}
/**
* Fills the list based on positioning the new selection relative to the old
* selection. The new selection will be placed at, above, or below the
* location of the new selection depending on how the selection is moving.
* The selection will then be pinned to the visible part of the screen,
* excluding the edges that are faded. The list is then filled upwards and
* downwards from there.
*
* @param oldSel The old selected view. Useful for trying to put the new
* selection in the same place
* @param newSel The view that is to become selected. Useful for trying to
* put the new selection in the same place
* @param delta Which way we are moving
* @param childrenLeft Where to start drawing children
* @param childrenRight Last pixel where children can be drawn
* @return The view that currently has selection
*/
private View moveSelection(View oldSel, View newSel, int delta, int childrenLeft,
int childrenRight) {
int fadingEdgeLength = getHorizontalFadingEdgeLength();
final int selectedPosition = mSelectedPosition;
View sel;
final int leftSelectionPixel = getLeftSelectionPixel(childrenLeft, fadingEdgeLength,
selectedPosition);
final int rightSelectionPixel = getRightSelectionPixel(childrenLeft, fadingEdgeLength,
selectedPosition);
if (delta > 0) {
/*
* Case 1: Scrolling down.
*/
/*
* Before After
* | | | |
* +-------+ +-------+
* | A | | A |
* | 1 | => +-------+
* +-------+ | B |
* | B | | 2 |
* +-------+ +-------+
* | | | |
*
* Try to keep the top of the previously selected item where it was.
* oldSel = A
* sel = B
*/
// Put oldSel (A) where it belongs
oldSel = makeAndAddView(selectedPosition - 1, oldSel.getLeft(), true,
mListPadding.top, false);
final int dividerWidth = mDividerWidth;
// Now put the new selection (B) below that
sel = makeAndAddView(selectedPosition, oldSel.getRight() + dividerWidth, true,
mListPadding.top, true);
// Some of the newly selected item extends below the bottom of the list
if (sel.getRight() > rightSelectionPixel) {
// Find space available above the selection into which we can scroll upwards
int spaceAbove = sel.getLeft() - leftSelectionPixel;
// Find space required to bring the bottom of the selected item fully into view
int spaceBelow = sel.getRight() - rightSelectionPixel;
// Don't scroll more than half the width of the list
int halfHorizontalSpace = (childrenRight - childrenLeft) / 2;
int offset = Math.min(spaceAbove, spaceBelow);
offset = Math.min(offset, halfHorizontalSpace);
// We placed oldSel, so offset that item
oldSel.offsetLeftAndRight(-offset);
// Now offset the selected item to get it into view
sel.offsetLeftAndRight(-offset);
}
// Fill in views above and below
if (!mStackFromRight) {
fillLeft(mSelectedPosition - 2, sel.getLeft() - dividerWidth);
adjustViewsLeftOrRight();
fillRight(mSelectedPosition + 1, sel.getRight() + dividerWidth);
} else {
fillRight(mSelectedPosition + 1, sel.getRight() + dividerWidth);
adjustViewsLeftOrRight();
fillLeft(mSelectedPosition - 2, sel.getLeft() - dividerWidth);
}
} else if (delta < 0) {
/*
* Case 2: Scrolling up.
*/
/*
* Before After
* | | | |
* +-------+ +-------+
* | A | | A |
* +-------+ => | 1 |
* | B | +-------+
* | 2 | | B |
* +-------+ +-------+
* | | | |
*
* Try to keep the top of the item about to become selected where it was.
* newSel = A
* olSel = B
*/
if (newSel != null) {
// Try to position the top of newSel (A) where it was before it was selected
sel = makeAndAddView(selectedPosition, newSel.getLeft(), true, mListPadding.top,
true);
} else {
// If (A) was not on screen and so did not have a view, position
// it above the oldSel (B)
sel = makeAndAddView(selectedPosition, oldSel.getLeft(), false, mListPadding.top,
true);
}
// Some of the newly selected item extends above the top of the list
if (sel.getLeft() < leftSelectionPixel) {
// Find space required to bring the top of the selected item fully into view
int spaceAbove = leftSelectionPixel - sel.getLeft();
// Find space available below the selection into which we can scroll downwards
int spaceBelow = rightSelectionPixel - sel.getRight();
// Don't scroll more than half the width of the list
int halfHorizontalSpace = (childrenRight - childrenLeft) / 2;
int offset = Math.min(spaceAbove, spaceBelow);
offset = Math.min(offset, halfHorizontalSpace);
// Offset the selected item to get it into view
sel.offsetLeftAndRight(offset);
}
// Fill in views above and below
fillToLeftAndRight(sel, selectedPosition);
} else {
int oldLeft = oldSel.getLeft();
/*
* Case 3: Staying still
*/
sel = makeAndAddView(selectedPosition, oldLeft, true, mListPadding.top, true);
// We're staying still...
if (oldLeft < childrenLeft) {
// ... but the top of the old selection was off screen.
// (This can happen if the data changes size out from under us)
int newRight = sel.getRight();
if (newRight < childrenLeft + 20) {
// Not enough visible -- bring it onscreen
sel.offsetLeftAndRight(childrenLeft - sel.getLeft());
}
}
// Fill in views above and below
fillToLeftAndRight(sel, selectedPosition);
}
return sel;
}
private class FocusSelector implements Runnable {
private int mPosition;
private int mPositionLeft;
public FocusSelector setup(int position, int left) {
mPosition = position;
mPositionLeft = left;
return this;
}
public void run() {
setSelectionFromLeft(mPosition, mPositionLeft);
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
if (getChildCount() > 0) {
View focusedChild = getFocusedChild();
if (focusedChild != null) {
final int childPosition = mFirstPosition + indexOfChild(focusedChild);
final int childRight = focusedChild.getRight();
final int offset = Math.max(0, childRight - (h - getPaddingLeft()));
final int left = focusedChild.getLeft() - offset;
if (mFocusSelector == null) {
mFocusSelector = new FocusSelector();
}
post(mFocusSelector.setup(childPosition, left));
}
}
super.onSizeChanged(w, h, oldw, oldh);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// Sets up mListPadding
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
int childWidth = 0;
int childHeight = 0;
int childState = 0;
mItemCount = mAdapter == null ? 0 : mAdapter.getCount();
if (mItemCount > 0 && (widthMode == MeasureSpec.UNSPECIFIED ||
heightMode == MeasureSpec.UNSPECIFIED)) {
final View child = obtainView(0, mIsScrap);
measureScrapChild(child, 0, heightMeasureSpec);
childWidth = child.getMeasuredWidth();
childHeight = child.getMeasuredHeight();
childState = Compat.combineMeasuredStates(childState, Compat.getMeasuredState(child));
if (recycleOnMeasure() && mRecycler.shouldRecycleViewType(
((LayoutParams) child.getLayoutParams()).viewType)) {
mRecycler.addScrapView(child, -1);
}
}
if (heightMode == MeasureSpec.UNSPECIFIED) {
heightSize = mListPadding.top + mListPadding.bottom + childHeight +
getHorizontalScrollbarHeight();
} else {
heightSize |= (childState&MEASURED_STATE_MASK);
}
if (widthMode == MeasureSpec.UNSPECIFIED) {
widthSize = mListPadding.left + mListPadding.right + childWidth +
getHorizontalFadingEdgeLength() * 2;
}
if (widthMode == MeasureSpec.AT_MOST) {
// TODO: after first layout we should maybe start at the first visible position, not 0
widthSize = measureWidthOfChildren(heightMeasureSpec, 0, NO_POSITION, widthSize, -1);
}
setMeasuredDimension(widthSize , heightSize);
mHeightMeasureSpec = heightMeasureSpec;
}
private void measureScrapChild(View child, int position, int heightMeasureSpec) {
LayoutParams p = (LayoutParams) child.getLayoutParams();
if (p == null) {
p = (LayoutParams) generateDefaultLayoutParams();
child.setLayoutParams(p);
}
p.viewType = mAdapter.getItemViewType(position);
p.forceAdd = true;
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightMeasureSpec,
mListPadding.top + mListPadding.bottom, p.height);
int lpWidth = p.width;
int childWidthSpec;
if (lpWidth > 0) {
childWidthSpec = MeasureSpec.makeMeasureSpec(lpWidth, MeasureSpec.EXACTLY);
} else {
childWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
}
child.measure(childWidthSpec, childHeightSpec);
}
/**
* @return True to recycle the views used to measure this ListView in
* UNSPECIFIED/AT_MOST modes, false otherwise.
* @hide
*/
@ViewDebug.ExportedProperty(category = "list")
protected boolean recycleOnMeasure() {
return true;
}
/**
* Measures the width of the given range of children (inclusive) and
* returns the width with this ListView's padding and divider heights
* included. If maxWidth is provided, the measuring will stop when the
* current width reaches maxWidth.
*
* @param heightMeasureSpec The width measure spec to be given to a child's
* {@link android.view.View#measure(int, int)}.
* @param startPosition The position of the first child to be shown.
* @param endPosition The (inclusive) position of the last child to be
* shown. Specify {@link #NO_POSITION} if the last child should be
* the last available child from the adapter.
* @param maxWidth The maximum width that will be returned (if all the
* children don't fit in this value, this value will be
* returned).
* @param disallowPartialChildPosition In general, whether the returned
* width should only contain entire children. This is more
* powerful--it is the first inclusive position at which partial
* children will not be allowed. Example: it looks nice to have
* at least 3 completely visible children, and in portrait this
* will most likely fit; but in landscape there could be times
* when even 2 children can not be completely shown, so a value
* of 2 (remember, inclusive) would be good (assuming
* startPosition is 0).
* @return The width of this ListView with the given children.
*/
final int measureWidthOfChildren(int heightMeasureSpec, int startPosition, int endPosition,
final int maxWidth, int disallowPartialChildPosition) {
final ListAdapter adapter = mAdapter;
if (adapter == null) {
return mListPadding.left + mListPadding.right;
}
// Include the padding of the list
int returnedWidth = mListPadding.left + mListPadding.right;
final int dividerWidth = ((mDividerWidth > 0) && mDivider != null) ? mDividerWidth : 0;
// The previous width value that was less than maxWidth and contained
// no partial children
int prevWidthWithoutPartialChild = 0;
int i;
View child;
// mItemCount - 1 since endPosition parameter is inclusive
endPosition = (endPosition == NO_POSITION) ? adapter.getCount() - 1 : endPosition;
final RecycleBin recycleBin = mRecycler;
final boolean recyle = recycleOnMeasure();
final boolean[] isScrap = mIsScrap;
for (i = startPosition; i <= endPosition; ++i) {
child = obtainView(i, isScrap);
measureScrapChild(child, i, heightMeasureSpec);
if (i > 0) {
// Count the divider for all but one child
returnedWidth += dividerWidth;
}
// Recycle the view before we possibly return from the method
if (recyle && recycleBin.shouldRecycleViewType(
((LayoutParams) child.getLayoutParams()).viewType)) {
recycleBin.addScrapView(child, -1);
}
returnedWidth += child.getMeasuredWidth();
if (returnedWidth >= maxWidth) {
// We went over, figure out which width to return. If returnedWidth > maxWidth,
// then the i'th position did not fit completely.
return (disallowPartialChildPosition >= 0) // Disallowing is enabled (> -1)
&& (i > disallowPartialChildPosition) // We've past the min pos
&& (prevWidthWithoutPartialChild > 0) // We have a prev width
&& (returnedWidth != maxWidth) // i'th child did not fit completely
? prevWidthWithoutPartialChild
: maxWidth;
}
if ((disallowPartialChildPosition >= 0) && (i >= disallowPartialChildPosition)) {
prevWidthWithoutPartialChild = returnedWidth;
}
}
// At this point, we went through the range of children, and they each
// completely fit, so return the returnedWidth
return returnedWidth;
}
@Override
int findMotionCol(int x) {
int childCount = getChildCount();
if (childCount > 0) {
if (!mStackFromRight) {
for (int i = 0; i < childCount; i++) {
View v = getChildAt(i);
if (x <= v.getRight()) {
return mFirstPosition + i;
}
}
} else {
for (int i = childCount - 1; i >= 0; i--) {
View v = getChildAt(i);
if (x >= v.getLeft()) {
return mFirstPosition + i;
}
}
}
}
return INVALID_POSITION;
}
/**
* Put a specific item at a specific location on the screen and then build
* up and down from there.
*
* @param position The reference view to use as the starting point
* @param left Pixel offset from the left of this view to the left of the
* reference view.
*
* @return The selected view, or null if the selected view is outside the
* visible area.
*/
private View fillSpecific(int position, int left) {
boolean tempIsSelected = position == mSelectedPosition;
View temp = makeAndAddView(position, left, true, mListPadding.top, tempIsSelected);
// Possibly changed again in fillRight if we add rows toLeft this one.
mFirstPosition = position;
View toLeft;
View toRight;
final int dividerWidth = mDividerWidth;
if (!mStackFromRight) {
toLeft = fillLeft(position - 1, temp.getLeft() - dividerWidth);
// This will correct for the left of the first view not touching the left of the list
adjustViewsLeftOrRight();
toRight = fillRight(position + 1, temp.getRight() + dividerWidth);
int childCount = getChildCount();
if (childCount > 0) {
correctTooHigh(childCount);
}
} else {
toRight = fillRight(position + 1, temp.getRight() + dividerWidth);
// This will correct for the bottom of the last view not touching the bottom of the list
adjustViewsLeftOrRight();
toLeft = fillLeft(position - 1, temp.getLeft() - dividerWidth);
int childCount = getChildCount();
if (childCount > 0) {
correctTooLow(childCount);
}
}
if (tempIsSelected) {
return temp;
} else if (toLeft != null) {
return toLeft;
} else {
return toRight;
}
}
/**
* Check if we have dragged the bottom of the list too high (we have pushed the
* top element off the top of the screen when we did not need to). Correct by sliding
* everything back down.
*
* @param childCount Number of children
*/
private void correctTooHigh(int childCount) {
// First see if the last item is visible. If it is not, it is OK for the
// top of the list to be pushed up.
int lastPosition = mFirstPosition + childCount - 1;
if (lastPosition == mItemCount - 1 && childCount > 0) {
// Get the last child ...
final View lastChild = getChildAt(childCount - 1);
// ... and its bottom edge
final int lastRight = lastChild.getRight();
// This is bottom of our drawable area
final int end = (getRight() - getLeft()) - mListPadding.right;
// This is how far the bottom edge of the last view is from the bottom of the
// drawable area
int bottomOffset = end - lastRight;
View firstChild = getChildAt(0);
final int firstLeft = firstChild.getLeft();
// Make sure we are 1) Too high, and 2) Either there are more rows above the
// first row or the first row is scrolled off the top of the drawable area
if (bottomOffset > 0 && (mFirstPosition > 0 || firstLeft < mListPadding.left)) {
if (mFirstPosition == 0) {
// Don't pull the top too far down
bottomOffset = Math.min(bottomOffset, mListPadding.left - firstLeft);
}
// Move everything down
offsetChildrenLeftAndRightUnhide(bottomOffset);
if (mFirstPosition > 0) {
// Fill the gap that was opened above mFirstPosition with more rows, if
// possible
fillLeft(mFirstPosition - 1, firstChild.getLeft() - mDividerWidth);
// Close up the remaining gap
adjustViewsLeftOrRight();
}
}
}
}
/**
* Check if we have dragged the bottom of the list too low (we have pushed the
* bottom element off the bottom of the screen when we did not need to). Correct by sliding
* everything back up.
*
* @param childCount Number of children
*/
private void correctTooLow(int childCount) {
// First see if the first item is visible. If it is not, it is OK for the
// bottom of the list to be pushed down.
if (mFirstPosition == 0 && childCount > 0) {
// Get the first child ...
final View firstChild = getChildAt(0);
// ... and its top edge
final int firstLeft = firstChild.getLeft();
// This is top of our drawable area
final int start = mListPadding.left;
// This is bottom of our drawable area
final int end = (getRight() - getLeft()) - mListPadding.right;
// This is how far the top edge of the first view is from the top of the
// drawable area
int leftOffset = firstLeft - start;
View lastChild = getChildAt(childCount - 1);
final int lastRight = lastChild.getRight();
int lastPosition = mFirstPosition + childCount - 1;
// Make sure we are 1) Too low, and 2) Either there are more rows below the
// last row or the last row is scrolled off the bottom of the drawable area
if (leftOffset > 0) {
if (lastPosition < mItemCount - 1 || lastRight > end) {
if (lastPosition == mItemCount - 1) {
// Don't pull the bottom too far up
leftOffset = Math.min(leftOffset, lastRight - end);
}
// Move everything up
offsetChildrenLeftAndRightUnhide(-leftOffset);
if (lastPosition < mItemCount - 1) {
// Fill the gap that was opened below the last position with more rows, if
// possible
fillRight(lastPosition + 1, lastChild.getRight() + mDividerWidth);
// Close up the remaining gap
adjustViewsLeftOrRight();
}
} else if (lastPosition == mItemCount - 1) {
adjustViewsLeftOrRight();
}
}
}
}
@Override
protected void layoutChildren() {
final boolean blockLayoutRequests = mBlockLayoutRequests;
if (!blockLayoutRequests) {
mBlockLayoutRequests = true;
} else {
return;
}
try {
super.layoutChildren();
invalidate();
if (mAdapter == null) {
resetList();
invokeOnItemScrollListener();
return;
}
int childrenLeft = mListPadding.left;
int childrenRight = getRight() - getLeft() - mListPadding.right;
int childCount = getChildCount();
int index = 0;
int delta = 0;
View sel;
View oldSel = null;
View oldFirst = null;
View newSel = null;
View focusLayoutRestoreView = null;
AccessibilityNodeInfo accessibilityFocusLayoutRestoreNode = null;
View accessibilityFocusLayoutRestoreView = null;
int accessibilityFocusPosition = INVALID_POSITION;
// Remember stuff we will need down below
switch (mLayoutMode) {
case LAYOUT_SET_SELECTION:
index = mNextSelectedPosition - mFirstPosition;
if (index >= 0 && index < childCount) {
newSel = getChildAt(index);
}
break;
case LAYOUT_FORCE_LEFT:
case LAYOUT_FORCE_RIGHT:
case LAYOUT_SPECIFIC:
case LAYOUT_SYNC:
break;
case LAYOUT_MOVE_SELECTION:
default:
// Remember the previously selected view
index = mSelectedPosition - mFirstPosition;
if (index >= 0 && index < childCount) {
oldSel = getChildAt(index);
}
// Remember the previous first child
oldFirst = getChildAt(0);
if (mNextSelectedPosition >= 0) {
delta = mNextSelectedPosition - mSelectedPosition;
}
// Caution: newSel might be null
newSel = getChildAt(index + delta);
}
boolean dataChanged = mDataChanged;
if (dataChanged) {
handleDataChanged();
}
// Handle the empty set by removing all views that are visible
// and calling it a day
if (mItemCount == 0) {
resetList();
invokeOnItemScrollListener();
return;
} else if (mItemCount != mAdapter.getCount()) {
throw new IllegalStateException("The content of the adapter has changed but "
+ "ListView did not receive a notification. Make sure the content of "
+ "your adapter is not modified from a background thread, but only "
+ "from the UI thread. [in ListView(" + getId() + ", " + getClass()
+ ") with Adapter(" + mAdapter.getClass() + ")]");
}
setSelectedPositionInt(mNextSelectedPosition);
// Pull all children into the RecycleBin.
// These views will be reused if possible
final int firstPosition = mFirstPosition;
final RecycleBin recycleBin = mRecycler;
// reset the focus restoration
View focusLayoutRestoreDirectChild = null;
// Don't put header or footer views into the Recycler. Those are
// already cached in mHeaderViews;
if (dataChanged) {
for (int i = 0; i < childCount; i++) {
recycleBin.addScrapView(getChildAt(i), firstPosition+i);
}
} else {
recycleBin.fillActiveViews(childCount, firstPosition);
}
// take focus back to us temporarily to avoid the eventual
// call to clear focus when removing the focused child below
// from messing things up when ViewAncestor assigns focus back
// to someone else
final View focusedChild = getFocusedChild();
if (focusedChild != null) {
// TODO: in some cases focusedChild.getParent() == null
// we can remember the focused view to restore after relayout if the
// data hasn't changed, or if the focused position is a header or footer
if (!dataChanged || isDirectChildHeaderOrFooter(focusedChild)) {
focusLayoutRestoreDirectChild = focusedChild;
// remember the specific view that had focus
focusLayoutRestoreView = findFocus();
if (focusLayoutRestoreView != null) {
// tell it we are going to mess with it
focusLayoutRestoreView.onStartTemporaryDetach();
}
}
requestFocus();
}
// TODO We can use those accessability methods, we just remove those (j.m.)
// //Remember which child, if any, had accessibility focus.
// final ViewRootImpl viewRootImpl = getViewRootImpl();
// if (viewRootImpl != null) {
// final View accessFocusedView = viewRootImpl.getAccessibilityFocusedHost();
// if (accessFocusedView != null) {
// final View accessFocusedChild = findAccessibilityFocusedChild(
// accessFocusedView);
// if (accessFocusedChild != null) {
// if (!dataChanged || isDirectChildHeaderOrFooter(accessFocusedChild)) {
// // If the views won't be changing, try to maintain
// // focus on the current view host and (if
// // applicable) its virtual view.
// accessibilityFocusLayoutRestoreView = accessFocusedView;
// accessibilityFocusLayoutRestoreNode = viewRootImpl
// .getAccessibilityFocusedVirtualView();
// } else {
// // Otherwise, try to maintain focus at the same
// // position.
// accessibilityFocusPosition = getPositionForView(accessFocusedChild);
// }
// }
// }
// }
// Clear out old views
detachAllViewsFromParent();
recycleBin.removeSkippedScrap();
switch (mLayoutMode) {
case LAYOUT_SET_SELECTION:
if (newSel != null) {
sel = fillFromSelection(newSel.getLeft(), childrenLeft, childrenRight);
} else {
sel = fillFromMiddle(childrenLeft, childrenRight);
}
break;
case LAYOUT_SYNC:
sel = fillSpecific(mSyncPosition, mSpecificLeft);
break;
case LAYOUT_FORCE_RIGHT:
sel = fillLeft(mItemCount - 1, childrenRight);
adjustViewsLeftOrRight();
break;
case LAYOUT_FORCE_LEFT:
mFirstPosition = 0;
sel = fillFromLeft(childrenLeft);
adjustViewsLeftOrRight();
break;
case LAYOUT_SPECIFIC:
sel = fillSpecific(reconcileSelectedPosition(), mSpecificLeft);
break;
case LAYOUT_MOVE_SELECTION:
sel = moveSelection(oldSel, newSel, delta, childrenLeft, childrenRight);
break;
default:
if (childCount == 0) {
if (!mStackFromRight) {
final int position = lookForSelectablePosition(0, true);
setSelectedPositionInt(position);
sel = fillFromLeft(childrenLeft);
} else {
final int position = lookForSelectablePosition(mItemCount - 1, false);
setSelectedPositionInt(position);
sel = fillLeft(mItemCount - 1, childrenRight);
}
} else {
if (mSelectedPosition >= 0 && mSelectedPosition < mItemCount) {
sel = fillSpecific(mSelectedPosition,
oldSel == null ? childrenLeft : oldSel.getLeft());
} else if (mFirstPosition < mItemCount) {
sel = fillSpecific(mFirstPosition,
oldFirst == null ? childrenLeft : oldFirst.getLeft());
} else {
sel = fillSpecific(0, childrenLeft);
}
}
break;
}
// Flush any cached views that did not get reused above
recycleBin.scrapActiveViews();
if (sel != null) {
// the current selected item should get focus if items
// are focusable
if (mItemsCanFocus && hasFocus() && !sel.hasFocus()) {
final boolean focusWasTaken = (sel == focusLayoutRestoreDirectChild &&
focusLayoutRestoreView != null &&
focusLayoutRestoreView.requestFocus()) || sel.requestFocus();
if (!focusWasTaken) {
// selected item didn't take focus, fine, but still want
// to make sure something else outside of the selected view
// has focus
final View focused = getFocusedChild();
if (focused != null) {
focused.clearFocus();
}
positionSelector(INVALID_POSITION, sel);
} else {
sel.setSelected(false);
mSelectorRect.setEmpty();
}
} else {
positionSelector(INVALID_POSITION, sel);
}
mSelectedLeft = sel.getLeft();
} else {
if (mTouchMode > TOUCH_MODE_DOWN && mTouchMode < TOUCH_MODE_SCROLL) {
View child = getChildAt(mMotionPosition - mFirstPosition);
if (child != null) positionSelector(mMotionPosition, child);
} else {
mSelectedLeft = 0;
mSelectorRect.setEmpty();
}
// even if there is not selected position, we may need to restore
// focus (i.e. something focusable in touch mode)
if (hasFocus() && focusLayoutRestoreView != null) {
focusLayoutRestoreView.requestFocus();
}
}
// TODO We can use those accessability methods, we just remove those (j.m.)
// // Attempt to restore accessibility focus.
// if (accessibilityFocusLayoutRestoreNode != null) {
// accessibilityFocusLayoutRestoreNode.performAction(
// AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS);
// } else if (accessibilityFocusLayoutRestoreView != null) {
// accessibilityFocusLayoutRestoreView.requestAccessibilityFocus();
// } else if (accessibilityFocusPosition != INVALID_POSITION) {
// // Bound the position within the visible children.
// final int position = MathUtils.constrain(
// (accessibilityFocusPosition - mFirstPosition), 0, (getChildCount() - 1));
// final View restoreView = getChildAt(position);
// if (restoreView != null) {
// restoreView.requestAccessibilityFocus();
// }
// }
// tell focus view we are done mucking with it, if it is still in
// our view hierarchy.
if (focusLayoutRestoreView != null
&& focusLayoutRestoreView.getWindowToken() != null) {
focusLayoutRestoreView.onFinishTemporaryDetach();
}
mLayoutMode = LAYOUT_NORMAL;
mDataChanged = false;
if (mPositionScrollAfterLayout != null) {
post(mPositionScrollAfterLayout);
mPositionScrollAfterLayout = null;
}
mNeedSync = false;
setNextSelectedPositionInt(mSelectedPosition);
updateScrollIndicators();
if (mItemCount > 0) {
checkSelectionChanged();
}
invokeOnItemScrollListener();
} finally {
if (!blockLayoutRequests) {
mBlockLayoutRequests = false;
}
}
}
/**
* @param focusedView the view that has accessibility focus.
* @return the direct child that contains accessibility focus.
*/
private View findAccessibilityFocusedChild(View focusedView) {
ViewParent viewParent = focusedView.getParent();
while ((viewParent instanceof View) && (viewParent != this)) {
focusedView = (View) viewParent;
viewParent = viewParent.getParent();
}
if (!(viewParent instanceof View)) {
return null;
}
return focusedView;
}
/**
* @param child a direct child of this list.
* @return Whether child is a header or footer view.
*/
private boolean isDirectChildHeaderOrFooter(View child) {
final ArrayList<ListView.FixedViewInfo> headers = mHeaderViewInfos;
final int numHeaders = headers.size();
for (int i = 0; i < numHeaders; i++) {
if (child == headers.get(i).view) {
return true;
}
}
final ArrayList<ListView.FixedViewInfo> footers = mFooterViewInfos;
final int numFooters = footers.size();
for (int i = 0; i < numFooters; i++) {
if (child == footers.get(i).view) {
return true;
}
}
return false;
}
/**
* Obtain the view and add it to our list of children. The view can be made
* fresh, converted from an unused view, or used as is if it was in the
* recycle bin.
*
* @param position Logical position in the list
* @param x Top or bottom edge of the view to add
* @param flow If flow is true, align top edge to x. If false, align bottom
* edge to x.
* @param childTop Left edge where children should be positioned
* @param selected Is this position selected?
* @return View that was added
*/
private View makeAndAddView(int position, int x, boolean flow, int childTop,
boolean selected) {
View child;
if (!mDataChanged) {
// Try to use an existing view for this position
child = mRecycler.getActiveView(position);
if (child != null) {
// Found it -- we're using an existing child
// This just needs to be positioned
setupChild(child, position, x, flow, childTop, selected, true);
return child;
}
}
// Make a new view for this position, or convert an unused view if possible
child = obtainView(position, mIsScrap);
// This needs to be positioned and measured
setupChild(child, position, x, flow, childTop, selected, mIsScrap[0]);
return child;
}
/**
* Add a view as a child and make sure it is measured (if necessary) and
* positioned properly.
*
* @param child The view to add
* @param position The position of this child
* @param x The x position relative to which this view will be positioned
* @param flowRight If true, align top edge to x. If false, align bottom
* edge to x.
* @param childTop Left edge where children should be positioned
* @param selected Is this position selected?
* @param recycled Has this view been pulled from the recycle bin? If so it
* does not need to be remeasured.
*/
private void setupChild(View child, int position, int x, boolean flowRight, int childTop,
boolean selected, boolean recycled) {
final boolean isSelected = selected && shouldShowSelector();
final boolean updateChildSelected = isSelected != child.isSelected();
final int mode = mTouchMode;
final boolean isPressed = mode > TOUCH_MODE_DOWN && mode < TOUCH_MODE_SCROLL &&
mMotionPosition == position;
final boolean updateChildPressed = isPressed != child.isPressed();
final boolean needToMeasure = !recycled || updateChildSelected || child.isLayoutRequested();
// Respect layout params that are already in the view. Otherwise make some up...
// noinspection unchecked
LayoutParams p = (LayoutParams) child.getLayoutParams();
if (p == null) {
p = (LayoutParams) generateDefaultLayoutParams();
}
p.viewType = mAdapter.getItemViewType(position);
if ((recycled && !p.forceAdd) || (p.recycledHeaderFooter &&
p.viewType == AdapterView.ITEM_VIEW_TYPE_HEADER_OR_FOOTER)) {
attachViewToParent(child, flowRight ? -1 : 0, p);
} else {
p.forceAdd = false;
if (p.viewType == AdapterView.ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
p.recycledHeaderFooter = true;
}
addViewInLayout(child, flowRight ? -1 : 0, p, true);
}
if (updateChildSelected) {
child.setSelected(isSelected);
}
if (updateChildPressed) {
child.setPressed(isPressed);
}
if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) {
if (child instanceof Checkable) {
((Checkable) child).setChecked(mCheckStates.get(position));
} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
Compat.setActivated(child, mCheckStates.get(position));
}
}
if (needToMeasure) {
int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec,
mListPadding.top + mListPadding.bottom, p.height);
int lpWidth = p.width;
int childWidthSpec;
if (lpWidth > 0) {
childWidthSpec = MeasureSpec.makeMeasureSpec(lpWidth, MeasureSpec.EXACTLY);
} else {
childWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
}
child.measure(childWidthSpec, childHeightSpec);
} else {
cleanupLayoutState(child);
}
final int w = child.getMeasuredWidth();
final int h = child.getMeasuredHeight();
final int childLeft = flowRight ? x : x - w;
if (needToMeasure) {
final int childBottom = childTop + h;
final int childRight = childLeft + w;
child.layout(childLeft, childTop, childRight, childBottom);
} else {
child.offsetTopAndBottom(childTop - child.getTop());
child.offsetLeftAndRight(childLeft - child.getLeft());
}
if (mCachingStarted && !child.isDrawingCacheEnabled()) {
child.setDrawingCacheEnabled(true);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB &&
recycled && (((LayoutParams)child.getLayoutParams()).scrappedFromPosition)
!= position) {
Compat.jumpDrawablesToCurrentState(child);
}
}
@Override
protected boolean canAnimate() {
return super.canAnimate() && mItemCount > 0;
}
/**
* Sets the currently selected item. If in touch mode, the item will not be selected
* but it will still be positioned appropriately. If the specified selection position
* is less than 0, then the item at position 0 will be selected.
*
* @param position Index (starting at 0) of the data item to be selected.
*/
@Override
public void setSelection(int position) {
setSelectionFromLeft(position, 0);
}
/**
* Sets the selected item and positions the selection x pixels from the top edge
* of the ListView. (If in touch mode, the item will not be selected but it will
* still be positioned appropriately.)
*
* @param position Index (starting at 0) of the data item to be selected.
* @param x The distance from the top edge of the ListView (plus padding) that the
* item will be positioned.
*/
public void setSelectionFromLeft(int position, int x) {
if (mAdapter == null) {
return;
}
if (!isInTouchMode()) {
position = lookForSelectablePosition(position, true);
if (position >= 0) {
setNextSelectedPositionInt(position);
}
} else {
mResurrectToPosition = position;
}
if (position >= 0) {
mLayoutMode = LAYOUT_SPECIFIC;
mSpecificLeft = mListPadding.left + x;
if (mNeedSync) {
mSyncPosition = position;
mSyncColId = mAdapter.getItemId(position);
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
requestLayout();
}
}
/**
* Makes the item at the supplied position selected.
*
* @param position the position of the item to select
*/
@Override
void setSelectionInt(int position) {
setNextSelectedPositionInt(position);
boolean awakeScrollbars = false;
final int selectedPosition = mSelectedPosition;
if (selectedPosition >= 0) {
if (position == selectedPosition - 1) {
awakeScrollbars = true;
} else if (position == selectedPosition + 1) {
awakeScrollbars = true;
}
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
layoutChildren();
if (awakeScrollbars) {
awakenScrollBars();
}
}
/**
* Find a position that can be selected (i.e., is not a separator).
*
* @param position The starting position to look at.
* @param lookRight Whether to look down for other positions.
* @return The next selectable position starting at position and then searching either up or
* down. Returns {@link #INVALID_POSITION} if nothing can be found.
*/
@Override
int lookForSelectablePosition(int position, boolean lookRight) {
final ListAdapter adapter = mAdapter;
if (adapter == null || isInTouchMode()) {
return INVALID_POSITION;
}
final int count = adapter.getCount();
if (!mAreAllItemsSelectable) {
if (lookRight) {
position = Math.max(0, position);
while (position < count && !adapter.isEnabled(position)) {
position++;
}
} else {
position = Math.min(position, count - 1);
while (position >= 0 && !adapter.isEnabled(position)) {
position--;
}
}
if (position < 0 || position >= count) {
return INVALID_POSITION;
}
return position;
} else {
if (position < 0 || position >= count) {
return INVALID_POSITION;
}
return position;
}
}
/**
* setSelectionAfterHeaderView set the selection to be the first list item
* after the header views.
*/
public void setSelectionAfterHeaderView() {
final int count = mHeaderViewInfos.size();
if (count > 0) {
mNextSelectedPosition = 0;
return;
}
if (mAdapter != null) {
setSelection(count);
} else {
mNextSelectedPosition = count;
mLayoutMode = LAYOUT_SET_SELECTION;
}
}
@Override
public boolean dispatchKeyEvent(KeyEvent event) {
// Dispatch in the normal way
boolean handled = super.dispatchKeyEvent(event);
if (!handled) {
// If we didn't handle it...
View focused = getFocusedChild();
if (focused != null && event.getAction() == KeyEvent.ACTION_DOWN) {
// ... and our focused child didn't handle it
// ... give it to ourselves so we can scroll if necessary
handled = onKeyDown(event.getKeyCode(), event);
}
}
return handled;
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
return commonKey(keyCode, 1, event);
}
@Override
public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event) {
return commonKey(keyCode, repeatCount, event);
}
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
return commonKey(keyCode, 1, event);
}
private boolean commonKey(int keyCode, int count, KeyEvent event) {
if (mAdapter == null || !mIsAttached) {
return false;
}
// TODO I stopped swaping heare (j.m.)
if (mDataChanged) {
layoutChildren();
}
boolean handled = false;
int action = event.getAction();
if (action != KeyEvent.ACTION_UP) {
switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_RIGHT:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded();
if (!handled) {
while (count-- > 0) {
if (arrowScroll(FOCUS_RIGHT)) {
handled = true;
} else {
break;
}
}
}
} else if (KeyEventCompat.hasModifiers(event, KeyEvent.META_ALT_ON)) {
handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_RIGHT);
}
break;
case KeyEvent.KEYCODE_DPAD_LEFT:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded();
if (!handled) {
while (count-- > 0) {
if (arrowScroll(FOCUS_LEFT)) {
handled = true;
} else {
break;
}
}
}
} else if (KeyEventCompat.hasModifiers(event, KeyEvent.META_ALT_ON)) {
handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_LEFT);
}
break;
case KeyEvent.KEYCODE_DPAD_UP:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = handleHorizontalFocusWithinListItem(View.FOCUS_UP);
}
break;
case KeyEvent.KEYCODE_DPAD_DOWN:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = handleHorizontalFocusWithinListItem(View.FOCUS_DOWN);
}
break;
case KeyEvent.KEYCODE_DPAD_CENTER:
case KeyEvent.KEYCODE_ENTER:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded();
if (!handled
&& event.getRepeatCount() == 0 && getChildCount() > 0) {
keyPressed();
handled = true;
}
}
break;
case KeyEvent.KEYCODE_SPACE:
if (mPopup == null || !mPopup.isShowing()) {
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_RIGHT);
} else if (KeyEventCompat.hasModifiers(event, KeyEvent.META_SHIFT_ON)) {
handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_LEFT);
}
handled = true;
}
break;
case KeyEvent.KEYCODE_PAGE_UP:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_LEFT);
} else if (KeyEventCompat.hasModifiers(event, KeyEvent.META_ALT_ON)) {
handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_LEFT);
}
break;
case KeyEvent.KEYCODE_PAGE_DOWN:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_RIGHT);
} else if (KeyEventCompat.hasModifiers(event, KeyEvent.META_ALT_ON)) {
handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_RIGHT);
}
break;
case KeyEvent.KEYCODE_MOVE_HOME:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_LEFT);
}
break;
case KeyEvent.KEYCODE_MOVE_END:
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_RIGHT);
}
break;
case KeyEvent.KEYCODE_TAB:
// XXX Sometimes it is useful to be able to TAB through the items in
// a ListView sequentially. Unfortunately this can create an
// asymmetry in TAB navigation order unless the list selection
// always reverts to the top or bottom when receiving TAB focus from
// another widget. Leaving this behavior disabled for now but
// perhaps it should be configurable (and more comprehensive).
if (false) {
if (KeyEventCompat.hasNoModifiers(event)) {
handled = resurrectSelectionIfNeeded() || arrowScroll(FOCUS_RIGHT);
} else if (KeyEventCompat.hasModifiers(event, KeyEvent.META_SHIFT_ON)) {
handled = resurrectSelectionIfNeeded() || arrowScroll(FOCUS_LEFT);
}
}
break;
}
}
if (handled) {
return true;
}
if (sendToTextFilter(keyCode, count, event)) {
return true;
}
switch (action) {
case KeyEvent.ACTION_DOWN:
return super.onKeyDown(keyCode, event);
case KeyEvent.ACTION_UP:
return super.onKeyUp(keyCode, event);
case KeyEvent.ACTION_MULTIPLE:
return super.onKeyMultiple(keyCode, count, event);
default: // shouldn't happen
return false;
}
}
/**
* Scrolls up or down by the number of items currently present on screen.
*
* @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}
* @return whether selection was moved
*/
boolean pageScroll(int direction) {
int nextPage = -1;
boolean down = false;
if (direction == FOCUS_UP) {
nextPage = Math.max(0, mSelectedPosition - getChildCount() - 1);
} else if (direction == FOCUS_DOWN) {
nextPage = Math.min(mItemCount - 1, mSelectedPosition + getChildCount() - 1);
down = true;
}
if (nextPage >= 0) {
int position = lookForSelectablePosition(nextPage, down);
if (position >= 0) {
mLayoutMode = LAYOUT_SPECIFIC;
mSpecificLeft = getPaddingLeft() + getHorizontalFadingEdgeLength();
if (down && position > mItemCount - getChildCount()) {
mLayoutMode = LAYOUT_FORCE_RIGHT;
}
if (!down && position < getChildCount()) {
mLayoutMode = LAYOUT_FORCE_LEFT;
}
setSelectionInt(position);
invokeOnItemScrollListener();
if (!awakenScrollBars()) {
invalidate();
}
return true;
}
}
return false;
}
/**
* Go to the last or first item if possible (not worrying about panning across or navigating
* within the internal focus of the currently selected item.)
*
* @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}
*
* @return whether selection was moved
*/
boolean fullScroll(int direction) {
boolean moved = false;
if (direction == FOCUS_LEFT) {
if (mSelectedPosition != 0) {
int position = lookForSelectablePosition(0, true);
if (position >= 0) {
mLayoutMode = LAYOUT_FORCE_LEFT;
setSelectionInt(position);
invokeOnItemScrollListener();
}
moved = true;
}
} else if (direction == FOCUS_RIGHT) {
if (mSelectedPosition < mItemCount - 1) {
int position = lookForSelectablePosition(mItemCount - 1, true);
if (position >= 0) {
mLayoutMode = LAYOUT_FORCE_RIGHT;
setSelectionInt(position);
invokeOnItemScrollListener();
}
moved = true;
}
}
if (moved && !awakenScrollBars()) {
awakenScrollBars();
invalidate();
}
return moved;
}
/**
* To avoid horizontal focus searches changing the selected item, we
* manually focus search within the selected item (as applicable), and
* prevent focus from jumping to something within another item.
* @param direction one of {View.FOCUS_LEFT, View.FOCUS_RIGHT}
* @return Whether this consumes the key event.
*/
private boolean handleHorizontalFocusWithinListItem(int direction) {
if (direction != View.FOCUS_UP && direction != View.FOCUS_DOWN) {
throw new IllegalArgumentException("direction must be one of"
+ " {View.FOCUS_UP, View.FOCUS_DOWN}");
}
final int numChildren = getChildCount();
if (mItemsCanFocus && numChildren > 0 && mSelectedPosition != INVALID_POSITION) {
final View selectedView = getSelectedView();
if (selectedView != null && selectedView.hasFocus() &&
selectedView instanceof ViewGroup) {
final View currentFocus = selectedView.findFocus();
final View nextFocus = FocusFinder.getInstance().findNextFocus(
(ViewGroup) selectedView, currentFocus, direction);
if (nextFocus != null) {
// do the math to get interesting rect in next focus' coordinates
currentFocus.getFocusedRect(mTempRect);
offsetDescendantRectToMyCoords(currentFocus, mTempRect);
offsetRectIntoDescendantCoords(nextFocus, mTempRect);
if (nextFocus.requestFocus(direction, mTempRect)) {
return true;
}
}
// we are blocking the key from being handled (by returning true)
// if the global result is going to be some other view within this
// list. this is to acheive the overall goal of having
// horizontal d-pad navigation remain in the current item.
final View globalNextFocus = FocusFinder.getInstance().findNextFocus(
(ViewGroup) getRootView(), currentFocus, direction);
if (globalNextFocus != null) {
return isViewAncestorOf(globalNextFocus, this);
}
}
}
return false;
}
/**
* Scrolls to the next or previous item if possible.
*
* @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}
*
* @return whether selection was moved
*/
boolean arrowScroll(int direction) {
try {
mInLayout = true;
final boolean handled = arrowScrollImpl(direction);
if (handled) {
playSoundEffect(SoundEffectConstants.getContantForFocusDirection(direction));
}
return handled;
} finally {
mInLayout = false;
}
}
/**
* Handle an arrow scroll going up or down. Take into account whether items are selectable,
* whether there are focusable items etc.
*
* @param direction Either {@link android.view.View#FOCUS_LEFT} or {@link android.view.View#FOCUS_RIGHT}.
* @return Whether any scrolling, selection or focus change occured.
*/
private boolean arrowScrollImpl(int direction) {
if (getChildCount() <= 0) {
return false;
}
View selectedView = getSelectedView();
int selectedPos = mSelectedPosition;
int nextSelectedPosition = (direction == View.FOCUS_RIGHT) ?
lookForSelectablePosition(selectedPos + 1, true) :
lookForSelectablePosition(selectedPos - 1, false);
int amountToScroll = amountToScroll(direction, nextSelectedPosition);
// if we are moving focus, we may OVERRIDE the default behavior
final ArrowScrollFocusResult focusResult = mItemsCanFocus ? arrowScrollFocused(direction) : null;
if (focusResult != null) {
nextSelectedPosition = focusResult.getSelectedPosition();
amountToScroll = focusResult.getAmountToScroll();
}
boolean needToRedraw = focusResult != null;
if (nextSelectedPosition != INVALID_POSITION) {
handleNewSelectionChange(selectedView, direction, nextSelectedPosition, focusResult != null);
setSelectedPositionInt(nextSelectedPosition);
setNextSelectedPositionInt(nextSelectedPosition);
selectedView = getSelectedView();
selectedPos = nextSelectedPosition;
if (mItemsCanFocus && focusResult == null) {
// there was no new view found to take focus, make sure we
// don't leave focus with the old selection
final View focused = getFocusedChild();
if (focused != null) {
focused.clearFocus();
}
}
needToRedraw = true;
checkSelectionChanged();
}
if (amountToScroll > 0) {
scrollListItemsBy((direction == View.FOCUS_UP) ? amountToScroll : -amountToScroll);
needToRedraw = true;
}
// if we didn't find a new focusable, make sure any existing focused
// item that was panned off screen gives up focus.
if (mItemsCanFocus && (focusResult == null)
&& selectedView != null && selectedView.hasFocus()) {
final View focused = selectedView.findFocus();
if (!isViewAncestorOf(focused, this) || distanceToView(focused) > 0) {
focused.clearFocus();
}
}
// if the current selection is panned off, we need to remove the selection
if (nextSelectedPosition == INVALID_POSITION && selectedView != null
&& !isViewAncestorOf(selectedView, this)) {
selectedView = null;
hideSelector();
// but we don't want to set the ressurect position (that would make subsequent
// unhandled key events bring back the item we just scrolled off!)
mResurrectToPosition = INVALID_POSITION;
}
if (needToRedraw) {
if (selectedView != null) {
positionSelector(selectedPos, selectedView);
mSelectedLeft = selectedView.getLeft();
}
if (!awakenScrollBars()) {
invalidate();
}
invokeOnItemScrollListener();
return true;
}
return false;
}
/**
* When selection changes, it is possible that the previously selected or the
* next selected item will change its size. If so, we need to offset some folks,
* and re-layout the items as appropriate.
*
* @param selectedView The currently selected view (before changing selection).
* should be <code>null</code> if there was no previous selection.
* @param direction Either {@link android.view.View#FOCUS_UP} or
* {@link android.view.View#FOCUS_DOWN}.
* @param newSelectedPosition The position of the next selection.
* @param newFocusAssigned whether new focus was assigned. This matters because
* when something has focus, we don't want to show selection (ugh).
*/
private void handleNewSelectionChange(View selectedView, int direction, int newSelectedPosition,
boolean newFocusAssigned) {
if (newSelectedPosition == INVALID_POSITION) {
throw new IllegalArgumentException("newSelectedPosition needs to be valid");
}
// whether or not we are moving down or up, we want to preserve the
// top of whatever view is on top:
// - moving down: the view that had selection
// - moving up: the view that is getting selection
View leftView;
View rightView;
int leftViewIndex, rightViewIndex;
boolean leftSelected = false;
final int selectedIndex = mSelectedPosition - mFirstPosition;
final int nextSelectedIndex = newSelectedPosition - mFirstPosition;
if (direction == View.FOCUS_LEFT) {
leftViewIndex = nextSelectedIndex;
rightViewIndex = selectedIndex;
leftView = getChildAt(leftViewIndex);
rightView = selectedView;
leftSelected = true;
} else {
leftViewIndex = selectedIndex;
rightViewIndex = nextSelectedIndex;
leftView = selectedView;
rightView = getChildAt(rightViewIndex);
}
final int numChildren = getChildCount();
// start with top view: is it changing size?
if (leftView != null) {
leftView.setSelected(!newFocusAssigned && leftSelected);
measureAndAdjustRight(leftView, leftViewIndex, numChildren);
}
// is the bottom view changing size?
if (rightView != null) {
rightView.setSelected(!newFocusAssigned && !leftSelected);
measureAndAdjustRight(rightView, rightViewIndex, numChildren);
}
}
/**
* Re-measure a child, and if its width changes, lay it out preserving its
* top, and adjust the children below it appropriately.
* @param child The child
* @param childIndex The view group index of the child.
* @param numChildren The number of children in the view group.
*/
private void measureAndAdjustRight(View child, int childIndex, int numChildren) {
int oldWidth = child.getWidth();
measureItem(child);
if (child.getMeasuredWidth() != oldWidth) {
// lay out the view, preserving its top
relayoutMeasuredItem(child);
// adjust views below appropriately
final int widthDelta = child.getMeasuredWidth() - oldWidth;
for (int i = childIndex + 1; i < numChildren; i++) {
getChildAt(i).offsetLeftAndRight(widthDelta);
}
}
}
/**
* Measure a particular list child.
* TODO: unify with setUpChild.
* @param child The child.
*/
private void measureItem(View child) {
ViewGroup.LayoutParams p = child.getLayoutParams();
if (p == null) {
p = new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
}
int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec,
mListPadding.top + mListPadding.bottom, p.height);
int lpWidth = p.width;
int childWidthSpec;
if (lpWidth > 0) {
childWidthSpec = MeasureSpec.makeMeasureSpec(lpWidth, MeasureSpec.EXACTLY);
} else {
childWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
}
child.measure(childWidthSpec, childHeightSpec);
}
/**
* Layout a child that has been measured, preserving its top position.
* TODO: unify with setUpChild.
* @param child The child.
*/
private void relayoutMeasuredItem(View child) {
final int w = child.getMeasuredWidth();
final int h = child.getMeasuredHeight();
final int childLeft = child.getLeft();
final int childRight = childLeft + w;
final int childTop = mListPadding.top;
final int childBottom = childTop + h;
child.layout(childLeft, childTop, childRight, childBottom);
}
/**
* @return The amount to preview next items when arrow srolling.
*/
private int getArrowScrollPreviewLength() {
return Math.max(MIN_SCROLL_PREVIEW_PIXELS, getHorizontalFadingEdgeLength());
}
/**
* Determine how much we need to scroll in order to get the next selected view
* visible, with a fading edge showing below as applicable. The amount is
* capped at {@link #getMaxScrollAmount()} .
*
* @param direction either {@link android.view.View#FOCUS_UP} or
* {@link android.view.View#FOCUS_DOWN}.
* @param nextSelectedPosition The position of the next selection, or
* {@link #INVALID_POSITION} if there is no next selectable position
* @return The amount to scroll. Note: this is always positive! Direction
* needs to be taken into account when actually scrolling.
*/
private int amountToScroll(int direction, int nextSelectedPosition) {
final int listRight = getWidth() - mListPadding.right;
final int listLeft = mListPadding.left;
int numChildren = getChildCount();
if (direction == View.FOCUS_DOWN) {
int indexToMakeVisible = numChildren - 1;
if (nextSelectedPosition != INVALID_POSITION) {
indexToMakeVisible = nextSelectedPosition - mFirstPosition;
}
while (numChildren <= indexToMakeVisible) {
// Child to view is not attached yet.
addViewToRight(getChildAt(numChildren - 1), mFirstPosition + numChildren - 1);
numChildren++;
}
final int positionToMakeVisible = mFirstPosition + indexToMakeVisible;
final View viewToMakeVisible = getChildAt(indexToMakeVisible);
int goalRight = listRight;
if (positionToMakeVisible < mItemCount - 1) {
goalRight -= getArrowScrollPreviewLength();
}
if (viewToMakeVisible.getRight() <= goalRight) {
// item is fully visible.
return 0;
}
if (nextSelectedPosition != INVALID_POSITION
&& (goalRight - viewToMakeVisible.getLeft()) >= getMaxScrollAmount()) {
// item already has enough of it visible, changing selection is good enough
return 0;
}
int amountToScroll = (viewToMakeVisible.getRight() - goalRight);
if ((mFirstPosition + numChildren) == mItemCount) {
// last is last in list -> make sure we don't scroll past it
final int max = getChildAt(numChildren - 1).getRight() - listRight;
amountToScroll = Math.min(amountToScroll, max);
}
return Math.min(amountToScroll, getMaxScrollAmount());
} else {
int indexToMakeVisible = 0;
if (nextSelectedPosition != INVALID_POSITION) {
indexToMakeVisible = nextSelectedPosition - mFirstPosition;
}
while (indexToMakeVisible < 0) {
// Child to view is not attached yet.
addViewToLeft(getChildAt(0), mFirstPosition);
mFirstPosition--;
indexToMakeVisible = nextSelectedPosition - mFirstPosition;
}
final int positionToMakeVisible = mFirstPosition + indexToMakeVisible;
final View viewToMakeVisible = getChildAt(indexToMakeVisible);
int goalLeft = listLeft;
if (positionToMakeVisible > 0) {
goalLeft += getArrowScrollPreviewLength();
}
if (viewToMakeVisible.getLeft() >= goalLeft) {
// item is fully visible.
return 0;
}
if (nextSelectedPosition != INVALID_POSITION &&
(viewToMakeVisible.getRight() - goalLeft) >= getMaxScrollAmount()) {
// item already has enough of it visible, changing selection is good enough
return 0;
}
int amountToScroll = (goalLeft - viewToMakeVisible.getLeft());
if (mFirstPosition == 0) {
// first is first in list -> make sure we don't scroll past it
final int max = listLeft - getChildAt(0).getLeft();
amountToScroll = Math.min(amountToScroll, max);
}
return Math.min(amountToScroll, getMaxScrollAmount());
}
}
/**
* Holds results of focus aware arrow scrolling.
*/
static private class ArrowScrollFocusResult {
private int mSelectedPosition;
private int mAmountToScroll;
/**
* How {@link com.appunite.list.HorizontalListView#arrowScrollFocused} returns its values.
*/
void populate(int selectedPosition, int amountToScroll) {
mSelectedPosition = selectedPosition;
mAmountToScroll = amountToScroll;
}
public int getSelectedPosition() {
return mSelectedPosition;
}
public int getAmountToScroll() {
return mAmountToScroll;
}
}
/**
* @param direction either {@link android.view.View#FOCUS_UP} or
* {@link android.view.View#FOCUS_DOWN}.
* @return The position of the next selectable position of the views that
* are currently visible, taking into account the fact that there might
* be no selection. Returns {@link #INVALID_POSITION} if there is no
* selectable view on screen in the given direction.
*/
private int lookForSelectablePositionOnScreen(int direction) {
final int firstPosition = mFirstPosition;
if (direction == View.FOCUS_DOWN) {
int startPos = (mSelectedPosition != INVALID_POSITION) ?
mSelectedPosition + 1 :
firstPosition;
if (startPos >= mAdapter.getCount()) {
return INVALID_POSITION;
}
if (startPos < firstPosition) {
startPos = firstPosition;
}
final int lastVisiblePos = getLastVisiblePosition();
final ListAdapter adapter = getAdapter();
for (int pos = startPos; pos <= lastVisiblePos; pos++) {
if (adapter.isEnabled(pos)
&& getChildAt(pos - firstPosition).getVisibility() == View.VISIBLE) {
return pos;
}
}
} else {
int last = firstPosition + getChildCount() - 1;
int startPos = (mSelectedPosition != INVALID_POSITION) ?
mSelectedPosition - 1 :
firstPosition + getChildCount() - 1;
if (startPos < 0 || startPos >= mAdapter.getCount()) {
return INVALID_POSITION;
}
if (startPos > last) {
startPos = last;
}
final ListAdapter adapter = getAdapter();
for (int pos = startPos; pos >= firstPosition; pos--) {
if (adapter.isEnabled(pos)
&& getChildAt(pos - firstPosition).getVisibility() == View.VISIBLE) {
return pos;
}
}
}
return INVALID_POSITION;
}
/**
* Do an arrow scroll based on focus searching. If a new view is
* given focus, return the selection delta and amount to scroll via
* an {@link ArrowScrollFocusResult}, otherwise, return null.
*
* @param direction either {@link android.view.View#FOCUS_UP} or
* {@link android.view.View#FOCUS_DOWN}.
* @return The result if focus has changed, or <code>null</code>.
*/
private ArrowScrollFocusResult arrowScrollFocused(final int direction) {
final View selectedView = getSelectedView();
View newFocus;
if (selectedView != null && selectedView.hasFocus()) {
View oldFocus = selectedView.findFocus();
newFocus = FocusFinder.getInstance().findNextFocus(this, oldFocus, direction);
} else {
if (direction == View.FOCUS_RIGHT) {
final boolean topFadingEdgeShowing = (mFirstPosition > 0);
final int listLeft = mListPadding.left +
(topFadingEdgeShowing ? getArrowScrollPreviewLength() : 0);
final int xSearchPoint =
(selectedView != null && selectedView.getLeft() > listLeft) ?
selectedView.getLeft() :
listLeft;
mTempRect.set(xSearchPoint, 0, xSearchPoint, 0);
} else {
final boolean rightFadingEdgeShowing =
(mFirstPosition + getChildCount() - 1) < mItemCount;
final int listRight = getWidth() - mListPadding.right -
(rightFadingEdgeShowing ? getArrowScrollPreviewLength() : 0);
final int xSearchPoint =
(selectedView != null && selectedView.getRight() < listRight) ?
selectedView.getRight() :
listRight;
mTempRect.set(xSearchPoint, 0, xSearchPoint, 0);
}
newFocus = FocusFinder.getInstance().findNextFocusFromRect(this, mTempRect, direction);
}
if (newFocus != null) {
final int positionOfNewFocus = positionOfNewFocus(newFocus);
// if the focus change is in a different new position, make sure
// we aren't jumping over another selectable position
if (mSelectedPosition != INVALID_POSITION && positionOfNewFocus != mSelectedPosition) {
final int selectablePosition = lookForSelectablePositionOnScreen(direction);
if (selectablePosition != INVALID_POSITION &&
((direction == View.FOCUS_RIGHT && selectablePosition < positionOfNewFocus) ||
(direction == View.FOCUS_LEFT && selectablePosition > positionOfNewFocus))) {
return null;
}
}
int focusScroll = amountToScrollToNewFocus(direction, newFocus, positionOfNewFocus);
final int maxScrollAmount = getMaxScrollAmount();
if (focusScroll < maxScrollAmount) {
// not moving too far, safe to give next view focus
newFocus.requestFocus(direction);
mArrowScrollFocusResult.populate(positionOfNewFocus, focusScroll);
return mArrowScrollFocusResult;
} else if (distanceToView(newFocus) < maxScrollAmount){
// Case to consider:
// too far to get entire next focusable on screen, but by going
// max scroll amount, we are getting it at least partially in view,
// so give it focus and scroll the max ammount.
newFocus.requestFocus(direction);
mArrowScrollFocusResult.populate(positionOfNewFocus, maxScrollAmount);
return mArrowScrollFocusResult;
}
}
return null;
}
/**
* @param newFocus The view that would have focus.
* @return the position that contains newFocus
*/
private int positionOfNewFocus(View newFocus) {
final int numChildren = getChildCount();
for (int i = 0; i < numChildren; i++) {
final View child = getChildAt(i);
if (isViewAncestorOf(newFocus, child)) {
return mFirstPosition + i;
}
}
throw new IllegalArgumentException("newFocus is not a child of any of the"
+ " children of the list!");
}
/**
* Return true if child is an ancestor of parent, (or equal to the parent).
*/
private boolean isViewAncestorOf(View child, View parent) {
if (child == parent) {
return true;
}
final ViewParent theParent = child.getParent();
return (theParent instanceof ViewGroup) && isViewAncestorOf((View) theParent, parent);
}
/**
* Determine how much we need to scroll in order to get newFocus in view.
* @param direction either {@link android.view.View#FOCUS_UP} or
* {@link android.view.View#FOCUS_DOWN}.
* @param newFocus The view that would take focus.
* @param positionOfNewFocus The position of the list item containing newFocus
* @return The amount to scroll. Note: this is always positive! Direction
* needs to be taken into account when actually scrolling.
*/
private int amountToScrollToNewFocus(int direction, View newFocus, int positionOfNewFocus) {
int amountToScroll = 0;
newFocus.getDrawingRect(mTempRect);
offsetDescendantRectToMyCoords(newFocus, mTempRect);
if (direction == View.FOCUS_LEFT) {
if (mTempRect.left < mListPadding.left) {
amountToScroll = mListPadding.left - mTempRect.left;
if (positionOfNewFocus > 0) {
amountToScroll += getArrowScrollPreviewLength();
}
}
} else {
final int listRight = getWidth() - mListPadding.right;
if (mTempRect.right > listRight) {
amountToScroll = mTempRect.right - listRight;
if (positionOfNewFocus < mItemCount - 1) {
amountToScroll += getArrowScrollPreviewLength();
}
}
}
return amountToScroll;
}
/**
* Determine the distance to the nearest edge of a view in a particular
* direction.
*
* @param descendant A descendant of this list.
* @return The distance, or 0 if the nearest edge is already on screen.
*/
private int distanceToView(View descendant) {
int distance = 0;
descendant.getDrawingRect(mTempRect);
offsetDescendantRectToMyCoords(descendant, mTempRect);
final int listRight = getRight() - getLeft() - mListPadding.right;
if (mTempRect.right < mListPadding.left) {
distance = mListPadding.left - mTempRect.right;
} else if (mTempRect.left > listRight) {
distance = mTempRect.left - listRight;
}
return distance;
}
/**
* Scroll the children by amount, adding a view at the end and removing
* views that fall off as necessary.
*
* @param amount The amount (positive or negative) to scroll.
*/
private void scrollListItemsBy(int amount) {
offsetChildrenLeftAndRightUnhide(amount);
final int listRight = getWidth() - mListPadding.right;
final int listLeft = mListPadding.left;
final RecycleBin recycleBin = mRecycler;
if (amount < 0) {
// shifted items up
// may need to pan views into the bottom space
int numChildren = getChildCount();
View last = getChildAt(numChildren - 1);
while (last.getRight() < listRight) {
final int lastVisiblePosition = mFirstPosition + numChildren - 1;
if (lastVisiblePosition < mItemCount - 1) {
last = addViewToRight(last, lastVisiblePosition);
numChildren++;
} else {
break;
}
}
// may have brought in the last child of the list that is skinnier
// than the fading edge, thereby leaving space at the end. need
// to shift back
if (last.getRight() < listRight) {
offsetChildrenLeftAndRightUnhide(listRight - last.getRight());
}
// top views may be panned off screen
View first = getChildAt(0);
while (first.getRight() < listLeft) {
LayoutParams layoutParams = (LayoutParams) first.getLayoutParams();
if (recycleBin.shouldRecycleViewType(layoutParams.viewType)) {
recycleBin.addScrapView(first, mFirstPosition);
}
detachViewFromParent(first);
first = getChildAt(0);
mFirstPosition++;
}
} else {
// shifted items down
View first = getChildAt(0);
// may need to pan views into top
while ((first.getLeft() > listLeft) && (mFirstPosition > 0)) {
first = addViewToLeft(first, mFirstPosition);
mFirstPosition--;
}
// may have brought the very first child of the list in too far and
// need to shift it back
if (first.getLeft() > listLeft) {
offsetChildrenLeftAndRightUnhide(listLeft - first.getLeft());
}
int lastIndex = getChildCount() - 1;
View last = getChildAt(lastIndex);
// bottom view may be panned off screen
while (last.getLeft() > listRight) {
LayoutParams layoutParams = (LayoutParams) last.getLayoutParams();
if (recycleBin.shouldRecycleViewType(layoutParams.viewType)) {
recycleBin.addScrapView(last, mFirstPosition+lastIndex);
}
detachViewFromParent(last);
last = getChildAt(--lastIndex);
}
}
}
private View addViewToLeft(View theView, int position) {
int abovePosition = position - 1;
View view = obtainView(abovePosition, mIsScrap);
int edgeOfNewChild = theView.getLeft() - mDividerWidth;
setupChild(view, abovePosition, edgeOfNewChild, false, mListPadding.top,
false, mIsScrap[0]);
return view;
}
private View addViewToRight(View theView, int position) {
int belowPosition = position + 1;
View view = obtainView(belowPosition, mIsScrap);
int edgeOfNewChild = theView.getRight() + mDividerWidth;
setupChild(view, belowPosition, edgeOfNewChild, true, mListPadding.top,
false, mIsScrap[0]);
return view;
}
/**
* Indicates that the views created by the ListAdapter can contain focusable
* items.
*
* @param itemsCanFocus true if items can get focus, false otherwise
*/
public void setItemsCanFocus(boolean itemsCanFocus) {
mItemsCanFocus = itemsCanFocus;
if (!itemsCanFocus) {
setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS);
}
}
/**
* @return Whether the views created by the ListAdapter can contain focusable
* items.
*/
public boolean getItemsCanFocus() {
return mItemsCanFocus;
}
@Override
public boolean isOpaque() {
boolean retValue = (mCachingActive && mIsCacheColorOpaque && mDividerIsOpaque &&
hasOpaqueScrollbarsUnhide()) || super.isOpaque();
if (retValue) {
// only return true if the list items cover the entire area of the view
final int listLeft = mListPadding != null ? mListPadding.left : getPaddingLeft();
View first = getChildAt(0);
if (first == null || first.getLeft() > listLeft) {
return false;
}
final int listRight = getRight() -
(mListPadding != null ? mListPadding.right : getPaddingRight());
View last = getChildAt(getChildCount() - 1);
if (last == null || last.getRight() < listRight) {
return false;
}
}
return retValue;
}
@Override
public void setCacheColorHint(int color) {
final boolean opaque = (color >>> 24) == 0xFF;
mIsCacheColorOpaque = opaque;
if (opaque) {
if (mDividerPaint == null) {
mDividerPaint = new Paint();
}
mDividerPaint.setColor(color);
}
super.setCacheColorHint(color);
}
void drawOverscrollHeader(Canvas canvas, Drawable drawable, Rect bounds) {
final int width = drawable.getMinimumWidth();
canvas.save();
canvas.clipRect(bounds);
final int span = bounds.right - bounds.left;
if (span < width) {
bounds.left = bounds.right - width;
}
drawable.setBounds(bounds);
drawable.draw(canvas);
canvas.restore();
}
void drawOverscrollFooter(Canvas canvas, Drawable drawable, Rect bounds) {
final int width = drawable.getMinimumWidth();
canvas.save();
canvas.clipRect(bounds);
final int span = bounds.right - bounds.left;
if (span < width) {
bounds.right = bounds.left + width;
}
drawable.setBounds(bounds);
drawable.draw(canvas);
canvas.restore();
}
@Override
protected void dispatchDraw(Canvas canvas) {
if (mCachingStarted) {
mCachingActive = true;
}
// Draw the dividers
final int dividerWidth = mDividerWidth;
final Drawable overscrollHeader = mOverScrollHeader;
final Drawable overscrollFooter = mOverScrollFooter;
final boolean drawOverscrollHeader = overscrollHeader != null;
final boolean drawOverscrollFooter = overscrollFooter != null;
final boolean drawDividers = dividerWidth > 0 && mDivider != null;
if (drawDividers || drawOverscrollHeader || drawOverscrollFooter) {
// Only modify the top and bottom in the loop, we set the left and right here
final Rect bounds = mTempRect;
bounds.top = getPaddingTop();
bounds.bottom = getBottom() - getTop() - getPaddingBottom();
final int count = getChildCount();
final int headerCount = mHeaderViewInfos.size();
final int itemCount = mItemCount;
final int footerLimit = itemCount - mFooterViewInfos.size() - 1;
final boolean headerDividers = mHeaderDividersEnabled;
final boolean footerDividers = mFooterDividersEnabled;
final int first = mFirstPosition;
final boolean areAllItemsSelectable = mAreAllItemsSelectable;
final ListAdapter adapter = mAdapter;
// If the list is opaque *and* the background is not, we want to
// fill a rect where the dividers would be for non-selectable items
// If the list is opaque and the background is also opaque, we don't
// need to draw anything since the background will do it for us
final boolean fillForMissingDividers = isOpaque() && !super.isOpaque();
if (fillForMissingDividers && mDividerPaint == null && mIsCacheColorOpaque) {
mDividerPaint = new Paint();
mDividerPaint.setColor(getCacheColorHint());
}
final Paint paint = mDividerPaint;
int effectivePaddingLeft = 0;
int effectivePaddingRight = 0;
if (mClipToPadding) {
effectivePaddingLeft = mListPadding.left;
effectivePaddingRight = mListPadding.right;
}
final int viewLeft = getLeft();
final int viewRight = getRight();
final int scrollX = getScrollX();
final int listRight = viewLeft - viewRight - effectivePaddingRight + scrollX;
if (!mStackFromRight) {
int right = 0;
// Draw top divider or header for overscroll
if (count > 0 && scrollX < 0) {
if (drawOverscrollHeader) {
bounds.right = 0;
bounds.left = scrollX;
drawOverscrollHeader(canvas, overscrollHeader, bounds);
} else if (drawDividers) {
bounds.right = 0;
bounds.left = -dividerWidth;
drawDivider(canvas, bounds, -1);
}
}
for (int i = 0; i < count; i++) {
if ((headerDividers || first + i >= headerCount) &&
(footerDividers || first + i < footerLimit)) {
View child = getChildAt(i);
right = child.getRight();
// Don't draw dividers next to items that are not enabled
if (drawDividers &&
(right < listRight && !(drawOverscrollFooter && i == count - 1))) {
if ((areAllItemsSelectable ||
(adapter.isEnabled(first + i) && (i == count - 1 ||
adapter.isEnabled(first + i + 1))))) {
bounds.left = right;
bounds.right = right + dividerWidth;
drawDivider(canvas, bounds, i);
} else if (fillForMissingDividers) {
bounds.left = right;
bounds.right = right + dividerWidth;
canvas.drawRect(bounds, paint);
}
}
}
}
final int overFooterRight = viewLeft + scrollX;
if (drawOverscrollFooter && first + count == itemCount &&
overFooterRight > right) {
bounds.left = right;
bounds.right = overFooterRight;
drawOverscrollFooter(canvas, overscrollFooter, bounds);
}
} else {
int left;
if (count > 0 && drawOverscrollHeader) {
bounds.left = scrollX;
bounds.right = getChildAt(0).getLeft();
drawOverscrollHeader(canvas, overscrollHeader, bounds);
}
final int start = drawOverscrollHeader ? 1 : 0;
for (int i = start; i < count; i++) {
if ((headerDividers || first + i >= headerCount) &&
(footerDividers || first + i < footerLimit)) {
View child = getChildAt(i);
left = child.getLeft();
// Don't draw dividers next to items that are not enabled
if (left > effectivePaddingLeft) {
if ((areAllItemsSelectable ||
(adapter.isEnabled(first + i) && (i == count - 1 ||
adapter.isEnabled(first + i + 1))))) {
bounds.left = left - dividerWidth;
bounds.right = left;
// Give the method the child ABOVE the divider, so we
// subtract one from our child
// position. Give -1 when there is no child above the
// divider.
drawDivider(canvas, bounds, i - 1);
} else if (fillForMissingDividers) {
bounds.left = left - dividerWidth;
bounds.right = left;
canvas.drawRect(bounds, paint);
}
}
}
}
if (count > 0 && scrollX > 0) {
if (drawOverscrollFooter) {
final int absListRight = viewLeft;
bounds.left = absListRight;
bounds.right = absListRight + scrollX;
drawOverscrollFooter(canvas, overscrollFooter, bounds);
} else if (drawDividers) {
bounds.left = listRight;
bounds.right = listRight + dividerWidth;
drawDivider(canvas, bounds, -1);
}
}
}
}
// Draw the indicators (these should be drawn above the dividers) and children
super.dispatchDraw(canvas);
}
@Override
protected boolean drawChild(Canvas canvas, View child, long drawingTime) {
boolean more = super.drawChild(canvas, child, drawingTime);
// TODO do not have access to cahing... try to ignore (j.m.)
// if (mCachingActive && child.mCachingFailed) {
if (mCachingActive) {
mCachingActive = false;
}
return more;
}
/**
* Draws a divider for the given child in the given bounds.
*
* @param canvas The canvas to draw to.
* @param bounds The bounds of the divider.
* @param childIndex The index of child (of the View) above the divider.
* This will be -1 if there is no child above the divider to be
* drawn.
*/
void drawDivider(Canvas canvas, Rect bounds, int childIndex) {
// This widget draws the same divider for all children
final Drawable divider = mDivider;
divider.setBounds(bounds);
divider.draw(canvas);
}
/**
* Returns the drawable that will be drawn between each item in the list.
*
* @return the current drawable drawn between list elements
*/
public Drawable getDivider() {
return mDivider;
}
/**
* Sets the drawable that will be drawn between each item in the list. If the drawable does
* not have an intrinsic width, you should also call {@link #setDividerWidth(int)}
*
* @param divider The drawable to use.
*/
public void setDivider(Drawable divider) {
if (divider != null) {
mDividerWidth = divider.getIntrinsicWidth();
} else {
mDividerWidth = 0;
}
mDivider = divider;
mDividerIsOpaque = divider == null || divider.getOpacity() == PixelFormat.OPAQUE;
requestLayout();
invalidate();
}
/**
* @return Returns the width of the divider that will be drawn between each item in the list.
*/
public int getDividerWidth() {
return mDividerWidth;
}
/**
* Sets the width of the divider that will be drawn between each item in the list. Calling
* this will override the intrinsic width as set by {@link #setDivider(android.graphics.drawable.Drawable)}
*
* @param width The new width of the divider in pixels.
*/
public void setDividerWidth(int width) {
mDividerWidth = width;
requestLayout();
invalidate();
}
/**
* Enables or disables the drawing of the divider for header views.
*
* @param headerDividersEnabled True to draw the headers, false otherwise.
*
* @see #setFooterDividersEnabled(boolean)
* @see #addHeaderView(android.view.View)
*/
public void setHeaderDividersEnabled(boolean headerDividersEnabled) {
mHeaderDividersEnabled = headerDividersEnabled;
invalidate();
}
/**
* Enables or disables the drawing of the divider for footer views.
*
* @param footerDividersEnabled True to draw the footers, false otherwise.
*
* @see #setHeaderDividersEnabled(boolean)
* @see #addFooterView(android.view.View)
*/
public void setFooterDividersEnabled(boolean footerDividersEnabled) {
mFooterDividersEnabled = footerDividersEnabled;
invalidate();
}
/**
* Sets the drawable that will be drawn above all other list content.
* This area can become visible when the user overscrolls the list.
*
* @param header The drawable to use
*/
public void setOverscrollHeader(Drawable header) {
mOverScrollHeader = header;
final int scrollX = getScrollX();
if (scrollX < 0) {
invalidate();
}
}
/**
* @return The drawable that will be drawn above all other list content
*/
public Drawable getOverscrollHeader() {
return mOverScrollHeader;
}
/**
* Sets the drawable that will be drawn below all other list content.
* This area can become visible when the user overscrolls the list,
* or when the list's content does not fully fill the container area.
*
* @param footer The drawable to use
*/
public void setOverscrollFooter(Drawable footer) {
mOverScrollFooter = footer;
invalidate();
}
/**
* @return The drawable that will be drawn below all other list content
*/
public Drawable getOverscrollFooter() {
return mOverScrollFooter;
}
@Override
protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) {
super.onFocusChanged(gainFocus, direction, previouslyFocusedRect);
final ListAdapter adapter = mAdapter;
int closetChildIndex = -1;
int closestChildLeft = 0;
if (adapter != null && gainFocus && previouslyFocusedRect != null) {
final int scrollX = getScrollX();
final int scrollY = getScrollY();
previouslyFocusedRect.offset(scrollX, scrollY);
// Don't cache the result of getChildCount or mFirstPosition here,
// it could change in layoutChildren.
if (adapter.getCount() < getChildCount() + mFirstPosition) {
mLayoutMode = LAYOUT_NORMAL;
layoutChildren();
}
// figure out which item should be selected based on previously
// focused rect
Rect otherRect = mTempRect;
int minDistance = Integer.MAX_VALUE;
final int childCount = getChildCount();
final int firstPosition = mFirstPosition;
for (int i = 0; i < childCount; i++) {
// only consider selectable views
if (!adapter.isEnabled(firstPosition + i)) {
continue;
}
View other = getChildAt(i);
other.getDrawingRect(otherRect);
offsetDescendantRectToMyCoords(other, otherRect);
int distance = getDistance(previouslyFocusedRect, otherRect, direction);
if (distance < minDistance) {
minDistance = distance;
closetChildIndex = i;
closestChildLeft = other.getLeft();
}
}
}
if (closetChildIndex >= 0) {
setSelectionFromLeft(closetChildIndex + mFirstPosition, closestChildLeft);
} else {
requestLayout();
}
}
/*
* (non-Javadoc)
*
* Children specified in XML are assumed to be header views. After we have
* parsed them move them out of the children list and into mHeaderViews.
*/
@Override
protected void onFinishInflate() {
super.onFinishInflate();
int count = getChildCount();
if (count > 0) {
for (int i = 0; i < count; ++i) {
addHeaderView(getChildAt(i));
}
removeAllViews();
}
}
// TODO Probably we do not need this (j.m.)
// /* (non-Javadoc)
// * @see android.view.View#findViewById(int)
// * First look in our children, then in any header and footer views that may be scrolled off.
// */
// @Override
// protected View findViewTraversal(int id) {
// View v = super.findViewTraversal(id);
// if (v == null) {
// v = findViewInHeadersOrFooters(mHeaderViewInfos, id);
// if (v != null) {
// return v;
// }
// v = findViewInHeadersOrFooters(mFooterViewInfos, id);
// if (v != null) {
// return v;
// }
// }
// return v;
// }
//
// /* (non-Javadoc)
// *
// * Look in the passed in list of headers or footers for the view.
// */
// View findViewInHeadersOrFooters(ArrayList<FixedViewInfo> where, int id) {
// if (where != null) {
// int len = where.size();
// View v;
//
// for (int i = 0; i < len; i++) {
// v = where.get(i).view;
//
// if (!v.isRootNamespace()) {
// v = v.findViewById(id);
//
// if (v != null) {
// return v;
// }
// }
// }
// }
// return null;
// }
//
// /* (non-Javadoc)
// * @see android.view.View#findViewWithTag(Object)
// * First look in our children, then in any header and footer views that may be scrolled off.
// */
// @Override
// protected View findViewWithTagTraversal(Object tag) {
// View v;
// v = super.findViewWithTagTraversal(tag);
// if (v == null) {
// v = findViewWithTagInHeadersOrFooters(mHeaderViewInfos, tag);
// if (v != null) {
// return v;
// }
//
// v = findViewWithTagInHeadersOrFooters(mFooterViewInfos, tag);
// if (v != null) {
// return v;
// }
// }
// return v;
// }
//
// /* (non-Javadoc)
// *
// * Look in the passed in list of headers or footers for the view with the tag.
// */
// View findViewWithTagInHeadersOrFooters(ArrayList<FixedViewInfo> where, Object tag) {
// if (where != null) {
// int len = where.size();
// View v;
//
// for (int i = 0; i < len; i++) {
// v = where.get(i).view;
//
// if (!v.isRootNamespace()) {
// v = v.findViewWithTag(tag);
//
// if (v != null) {
// return v;
// }
// }
// }
// }
// return null;
// }
//
// /**
// * @hide
// * @see android.view.View#findViewByPredicate(Predicate)
// * First look in our children, then in any header and footer views that may be scrolled off.
// */
// @Override
// protected View findViewByPredicateTraversal(Predicate<View> predicate, View childToSkip) {
// View v;
// v = super.findViewByPredicateTraversal(predicate, childToSkip);
// if (v == null) {
// v = findViewByPredicateInHeadersOrFooters(mHeaderViewInfos, predicate, childToSkip);
// if (v != null) {
// return v;
// }
//
// v = findViewByPredicateInHeadersOrFooters(mFooterViewInfos, predicate, childToSkip);
// if (v != null) {
// return v;
// }
// }
// return v;
// }
//
// /* (non-Javadoc)
// *
// * Look in the passed in list of headers or footers for the first view that matches
// * the predicate.
// */
// View findViewByPredicateInHeadersOrFooters(ArrayList<FixedViewInfo> where,
// Predicate<View> predicate, View childToSkip) {
// if (where != null) {
// int len = where.size();
// View v;
//
// for (int i = 0; i < len; i++) {
// v = where.get(i).view;
//
// if (v != childToSkip && !v.isRootNamespace()) {
// v = v.findViewByPredicate(predicate);
//
// if (v != null) {
// return v;
// }
// }
// }
// }
// return null;
// }
/**
* Returns the set of checked items ids. The result is only valid if the
* choice mode has not been set to {@link #CHOICE_MODE_NONE}.
*
* @return A new array which contains the id of each checked item in the
* list.
*
* @deprecated Use {@link #getCheckedItemIds()} instead.
*/
@Deprecated
public long[] getCheckItemIds() {
// Use new behavior that correctly handles stable ID mapping.
if (mAdapter != null && mAdapter.hasStableIds()) {
return getCheckedItemIds();
}
// Old behavior was buggy, but would sort of work for adapters without stable IDs.
// Fall back to it to support legacy apps.
if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null && mAdapter != null) {
final SparseBooleanArray states = mCheckStates;
final int count = states.size();
final long[] ids = new long[count];
final ListAdapter adapter = mAdapter;
int checkedCount = 0;
for (int i = 0; i < count; i++) {
if (states.valueAt(i)) {
ids[checkedCount++] = adapter.getItemId(states.keyAt(i));
}
}
// Trim array if needed. mCheckStates may contain false values
// resulting in checkedCount being smaller than count.
if (checkedCount == count) {
return ids;
} else {
final long[] result = new long[checkedCount];
System.arraycopy(ids, 0, result, 0, checkedCount);
return result;
}
}
return new long[0];
}
@Override
public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
super.onInitializeAccessibilityEvent(event);
event.setClassName(HorizontalListView.class.getName());
}
@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
@Override
public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfo(info);
info.setClassName(HorizontalListView.class.getName());
}
}