package com.example.internal;
/*
* 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.
*/
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.TransitionDrawable;
import android.os.Debug;
import android.os.Handler;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.AttributeSet;
import android.util.Log;
//import android.util.Log;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.Gravity;
import android.view.HapticFeedbackConstants;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewDebug;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.widget.Adapter;
import android.widget.Filterable;
import android.widget.ListAdapter;
import android.widget.PopupWindow;
import android.widget.Scroller;
import com.example.uilistviewtest.R;
/**
* Base class that can be used to implement virtualized lists of items. A list
* does not have a spatial definition here. For instance, subclases of this
* class can display the content of the list in a grid, in a carousel, as stack,
* etc.
*
* @attr ref android.R.styleable#AbsListView_listSelector
* @attr ref android.R.styleable#AbsListView_drawSelectorOnTop
* @attr ref android.R.styleable#AbsListView_stackFromBottom
* @attr ref android.R.styleable#AbsListView_scrollingCache
* @attr ref android.R.styleable#AbsListView_textFilterEnabled
* @attr ref android.R.styleable#AbsListView_transcriptMode
* @attr ref android.R.styleable#AbsListView_cacheColorHint
* @attr ref android.R.styleable#AbsListView_fastScrollEnabled
* @attr ref android.R.styleable#AbsListView_smoothScrollbar
*/
public abstract class AbsListView extends AdapterView<ListAdapter> implements
ViewTreeObserver.OnGlobalLayoutListener, ViewTreeObserver.OnTouchModeChangeListener {
/**
* Disables the transcript mode.
*
* @see #setTranscriptMode(int)
*/
public static final int TRANSCRIPT_MODE_DISABLED = 0;
/**
* The list will automatically scroll to the bottom when a data set change
* notification is received and only if the last item is already visible on
* screen.
*
* @see #setTranscriptMode(int)
*/
public static final int TRANSCRIPT_MODE_NORMAL = 1;
/**
* The list will automatically scroll to the bottom, no matter what items
* are currently visible.
*
* @see #setTranscriptMode(int)
*/
public static final int TRANSCRIPT_MODE_ALWAYS_SCROLL = 2;
/**
* Indicates that we are not in the middle of a touch gesture
*/
static final int TOUCH_MODE_REST = -1;
/**
* Indicates we just received the touch event and we are waiting to see if
* the it is a tap or a scroll gesture.
*/
static final int TOUCH_MODE_DOWN = 0;
/**
* Indicates the touch has been recognized as a tap and we are now waiting
* to see if the touch is a longpress
*/
static final int TOUCH_MODE_TAP = 1;
/**
* Indicates we have waited for everything we can wait for, but the user's
* finger is still down
*/
static final int TOUCH_MODE_DONE_WAITING = 2;
/**
* Indicates the touch gesture is a scroll
*/
static final int TOUCH_MODE_SCROLL = 3;
/**
* Indicates the view is in the process of being flung
*/
static final int TOUCH_MODE_FLING = 4;
/**
* Regular layout - usually an unsolicited layout from the view system
*/
static final int LAYOUT_NORMAL = 0;
/**
* Show the first item
*/
static final int LAYOUT_FORCE_TOP = 1;
/**
* Force the selected item to be on somewhere on the screen
*/
static final int LAYOUT_SET_SELECTION = 2;
/**
* Show the last item
*/
static final int LAYOUT_FORCE_BOTTOM = 3;
/**
* Make a mSelectedItem appear in a specific location and build the rest of
* the views from there. The top is specified by mSpecificTop.
*/
static final int LAYOUT_SPECIFIC = 4;
/**
* Layout to sync as a result of a data change. Restore mSyncPosition to
* have its top at mSpecificTop
*/
static final int LAYOUT_SYNC = 5;
/**
* Controls how the next layout will happen
*/
int mLayoutMode = LAYOUT_NORMAL;
protected int mColumnCount = 2;
protected ArrayList<View>[] mColumnViews = new ArrayList[mColumnCount];
protected Map<Integer, Integer> mPosIndexMap = new HashMap<Integer, Integer>();
/**
* Should be used by subclasses to listen to changes in the dataset
*/
AdapterDataSetObserver mDataSetObserver;
/**
* The adapter containing the data to be displayed by this view
*/
ListAdapter mAdapter;
/**
* Indicates whether the list selector should be drawn on top of the
* children or behind
*/
boolean mDrawSelectorOnTop = false;
/**
* The drawable used to draw the selector
*/
Drawable mSelector;
/**
* Defines the selector's location and dimension at drawing time
*/
Rect mSelectorRect = new Rect();
/**
* The data set used to store unused views that should be reused during the
* next layout to avoid creating new ones
*/
final RecycleBin mRecycler = new RecycleBin();
/**
* The selection's left padding
*/
int mSelectionLeftPadding = 0;
/**
* The selection's top padding
*/
int mSelectionTopPadding = 0;
/**
* The selection's right padding
*/
int mSelectionRightPadding = 0;
/**
* The selection's bottom padding
*/
int mSelectionBottomPadding = 0;
/**
* This view's padding
*/
Rect mListPadding = new Rect();
/**
* Subclasses must retain their measure spec from onMeasure() into this
* member
*/
int mWidthMeasureSpec = 0;
/**
* The top scroll indicator
*/
View mScrollUp;
/**
* The down scroll indicator
*/
View mScrollDown;
/**
* When the view is scrolling, this flag is set to true to indicate
* subclasses that the drawing cache was enabled on the children
*/
boolean mCachingStarted;
/**
* The position of the view that received the down motion event
*/
int mMotionPosition;
/**
* The offset to the top of the mMotionPosition view when the down motion
* event was received
*/
int mMotionViewOriginalTop;
/**
* The desired offset to the top of the mMotionPosition view after a scroll
*/
int mMotionViewNewTop;
/**
* The X value associated with the the down motion event
*/
int mMotionX;
/**
* The Y value associated with the the down motion event
*/
int mMotionY;
/**
* One of TOUCH_MODE_REST, TOUCH_MODE_DOWN, TOUCH_MODE_TAP,
* TOUCH_MODE_SCROLL, or TOUCH_MODE_DONE_WAITING
*/
int mTouchMode = TOUCH_MODE_REST;
/**
* Y value from on the previous motion event (if any)
*/
int mLastY;
/**
* How far the finger moved before we started scrolling
*/
int mMotionCorrection;
/**
* Determines speed during touch scrolling
*/
private VelocityTracker mVelocityTracker;
/**
* Handles one frame of a fling
*/
private FlingRunnable mFlingRunnable;
/**
* Handles scrolling between positions within the list.
*/
private PositionScroller mPositionScroller;
/**
* The offset in pixels form the top of the AdapterView to the top of the
* currently selected view. Used to save and restore state.
*/
int mSelectedTop = 0;
/**
* Indicates whether the list is stacked from the bottom edge or the top
* edge.
*/
boolean mStackFromBottom;
/**
* When set to true, the list automatically discards the children's bitmap
* cache after scrolling.
*/
boolean mScrollingCacheEnabled;
/**
* Whether or not to enable the fast scroll feature on this list
*/
boolean mFastScrollEnabled;
/**
* Optional callback to notify client when scroll position has changed
*/
private OnScrollListener mOnScrollListener;
/**
* Keeps track of our accessory window
*/
PopupWindow mPopup;
/**
* Indicates whether to use pixels-based or position-based scrollbar
* properties.
*/
private boolean mSmoothScrollbarEnabled = true;
/**
* Indicates that this view supports filtering
*/
private boolean mTextFilterEnabled;
/**
* Indicates that this view is currently displaying a filtered view of the
* data
*/
private boolean mFiltered;
/**
* Rectangle used for hit testing children
*/
private Rect mTouchFrame;
/**
* The position to resurrect the selected position to.
*/
int mResurrectToPosition = INVALID_POSITION;
private ContextMenuInfo mContextMenuInfo = null;
/**
* Used to request a layout when we changed touch mode
*/
private static final int TOUCH_MODE_UNKNOWN = -1;
private static final int TOUCH_MODE_ON = 0;
private static final int TOUCH_MODE_OFF = 1;
private int mLastTouchMode = TOUCH_MODE_UNKNOWN;
private static final boolean PROFILE_SCROLLING = false;
private boolean mScrollProfilingStarted = false;
private static final boolean PROFILE_FLINGING = false;
private boolean mFlingProfilingStarted = false;
/**
* The last CheckForLongPress runnable we posted, if any
*/
private CheckForLongPress mPendingCheckForLongPress;
/**
* The last CheckForTap runnable we posted, if any
*/
private Runnable mPendingCheckForTap;
/**
* The last CheckForKeyLongPress runnable we posted, if any
*/
private CheckForKeyLongPress mPendingCheckForKeyLongPress;
/**
* Acts upon click
*/
private AbsListView.PerformClick mPerformClick;
/**
* This view is in transcript mode -- it shows the bottom of the list when
* the data changes
*/
private int mTranscriptMode;
/**
* Indicates that this list is always drawn on top of a solid, single-color,
* opaque background
*/
private int mCacheColorHint;
/**
* The select child's view (from the adapter's getView) is enabled.
*/
private boolean mIsChildViewEnabled;
/**
* The last scroll state reported to clients through
* {@link OnScrollListener}.
*/
private int mLastScrollState = OnScrollListener.SCROLL_STATE_IDLE;
private boolean mGlobalLayoutListenerAddedFilter;
private int mTouchSlop;
private float mDensityScale;
private Runnable mClearScrollingCache;
private int mMinimumVelocity;
private int mMaximumVelocity;
final boolean[] mIsScrap = new boolean[1];
// True when the popup should be hidden because of a call to
// dispatchDisplayHint()
private boolean mPopupHidden;
/**
* ID of the active pointer. This is used to retain consistency during
* drags/flings if multiple pointers are used.
*/
private int mActivePointerId = INVALID_POINTER;
/**
* Sentinel value for no current active pointer. Used by
* {@link #mActivePointerId}.
*/
private static final int INVALID_POINTER = -1;
/**
* Interface definition for a callback to be invoked when the list or grid
* has been scrolled.
*/
public interface OnScrollListener {
/**
* The view is not scrolling. Note navigating the list using the
* trackball counts as being in the idle state since these transitions
* are not animated.
*/
public static int SCROLL_STATE_IDLE = 0;
/**
* The user is scrolling using touch, and their finger is still on the
* screen
*/
public static int SCROLL_STATE_TOUCH_SCROLL = 1;
/**
* The user had previously been scrolling using touch and had performed
* a fling. The animation is now coasting to a stop
*/
public static int SCROLL_STATE_FLING = 2;
/**
* Callback method to be invoked while the list view or grid view is
* being scrolled. If the view is being scrolled, this method will be
* called before the next frame of the scroll is rendered. In
* particular, it will be called before any calls to
* {@link Adapter#getView(int, View, ViewGroup)}.
*
* @param view
* The view whose scroll state is being reported
*
* @param scrollState
* The current scroll state. One of
* {@link #SCROLL_STATE_IDLE},
* {@link #SCROLL_STATE_TOUCH_SCROLL} or
* {@link #SCROLL_STATE_IDLE}.
*/
public void onScrollStateChanged(AbsListView view, int scrollState);
/**
* Callback method to be invoked when the list or grid has been
* scrolled. This will be called after the scroll has completed
*
* @param view
* The view whose scroll state is being reported
* @param firstVisibleItem
* the index of the first visible cell (ignore if
* visibleItemCount == 0)
* @param visibleItemCount
* the number of visible cells
* @param totalItemCount
* the number of items in the list adaptor
*/
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
int totalItemCount);
}
public AbsListView(Context context) {
super(context);
initAbsListView();
setVerticalScrollBarEnabled(true);
TypedArray a = context.obtainStyledAttributes(R.styleable.View);
initializeScrollbars(a);
a.recycle();
}
public AbsListView(Context context, AttributeSet attrs) {
this(context, attrs, R.attr.absListViewStyle);
}
public AbsListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initAbsListView();
TypedArray a = context.obtainStyledAttributes(attrs,
R.styleable.AbsListView, defStyle, 0);
Drawable d = a.getDrawable(R.styleable.AbsListView_listSelector);
if (d != null) {
setSelector(d);
}
mDrawSelectorOnTop = a.getBoolean(
R.styleable.AbsListView_drawSelectorOnTop, false);
boolean stackFromBottom = a.getBoolean(R.styleable.AbsListView_stackFromBottom, false);
setStackFromBottom(stackFromBottom);
boolean scrollingCacheEnabled = a.getBoolean(R.styleable.AbsListView_scrollingCache, true);
setScrollingCacheEnabled(scrollingCacheEnabled);
boolean useTextFilter = a.getBoolean(R.styleable.AbsListView_textFilterEnabled, false);
setTextFilterEnabled(useTextFilter);
int transcriptMode = a.getInt(R.styleable.AbsListView_transcriptMode,
TRANSCRIPT_MODE_DISABLED);
setTranscriptMode(transcriptMode);
int color = a.getColor(R.styleable.AbsListView_cacheColorHint, 0);
setCacheColorHint(color);
boolean smoothScrollbar = a.getBoolean(R.styleable.AbsListView_smoothScrollbar, true);
setSmoothScrollbarEnabled(smoothScrollbar);
a.recycle();
}
private void initAbsListView() {
// Setting focusable in touch mode will set the focusable property to
// true
setClickable(true);
setFocusableInTouchMode(true);
setWillNotDraw(false);
setAlwaysDrawnWithCacheEnabled(false);
setScrollingCacheEnabled(true);
final ViewConfiguration configuration = ViewConfiguration.get(getContext());
mTouchSlop = configuration.getScaledTouchSlop();
mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
mDensityScale = getContext().getResources().getDisplayMetrics().density;
}
/**
* Returns the current state of the fast scroll feature.
*
* @see #setFastScrollEnabled(boolean)
* @return true if fast scroll is enabled, false otherwise
*/
@ViewDebug.ExportedProperty
public boolean isFastScrollEnabled() {
return mFastScrollEnabled;
}
/**
* When smooth scrollbar is enabled, the position and size of the scrollbar
* thumb is computed based on the number of visible pixels in the visible
* items. This however assumes that all list items have the same height. If
* you use a list in which items have different heights, the scrollbar will
* change appearance as the user scrolls through the list. To avoid this
* issue, you need to disable this property.
*
* When smooth scrollbar is disabled, the position and size of the scrollbar
* thumb is based solely on the number of items in the adapter and the
* position of the visible items inside the adapter. This provides a stable
* scrollbar as the user navigates through a list of items with varying
* heights.
*
* @param enabled
* Whether or not to enable smooth scrollbar.
*
* @see #setSmoothScrollbarEnabled(boolean)
* @attr ref android.R.styleable#AbsListView_smoothScrollbar
*/
public void setSmoothScrollbarEnabled(boolean enabled) {
mSmoothScrollbarEnabled = enabled;
}
/**
* Returns the current state of the fast scroll feature.
*
* @return True if smooth scrollbar is enabled is enabled, false otherwise.
*
* @see #setSmoothScrollbarEnabled(boolean)
*/
@ViewDebug.ExportedProperty
public boolean isSmoothScrollbarEnabled() {
return mSmoothScrollbarEnabled;
}
/**
* Set the listener that will receive notifications every time the list
* scrolls.
*
* @param l
* the scroll listener
*/
public void setOnScrollListener(OnScrollListener l) {
mOnScrollListener = l;
invokeOnItemScrollListener();
}
/**
* Notify our scroll listener (if there is one) of a change in scroll state
*/
void invokeOnItemScrollListener() {
if (mOnScrollListener != null) {
mOnScrollListener.onScroll(this, mFirstPosition, getChildCount(), mItemCount);
}
}
/**
* Indicates whether the children's drawing cache is used during a scroll.
* By default, the drawing cache is enabled but this will consume more
* memory.
*
* @return true if the scrolling cache is enabled, false otherwise
*
* @see #setScrollingCacheEnabled(boolean)
* @see View#setDrawingCacheEnabled(boolean)
*/
@ViewDebug.ExportedProperty
public boolean isScrollingCacheEnabled() {
return mScrollingCacheEnabled;
}
/**
* Enables or disables the children's drawing cache during a scroll. By
* default, the drawing cache is enabled but this will use more memory.
*
* When the scrolling cache is enabled, the caches are kept after the first
* scrolling. You can manually clear the cache by calling
* {@link android.view.ViewGroup#setChildrenDrawingCacheEnabled(boolean)}.
*
* @param enabled
* true to enable the scroll cache, false otherwise
*
* @see #isScrollingCacheEnabled()
* @see View#setDrawingCacheEnabled(boolean)
*/
public void setScrollingCacheEnabled(boolean enabled) {
if (mScrollingCacheEnabled && !enabled) {
clearScrollingCache();
}
mScrollingCacheEnabled = enabled;
}
/**
* Enables or disables the type filter window. If enabled, typing when this
* view has focus will filter the children to match the users input. Note
* that the {@link Adapter} used by this view must implement the
* {@link Filterable} interface.
*
* @param textFilterEnabled
* true to enable type filtering, false otherwise
*
* @see Filterable
*/
public void setTextFilterEnabled(boolean textFilterEnabled) {
mTextFilterEnabled = textFilterEnabled;
}
/**
* Indicates whether type filtering is enabled for this view
*
* @return true if type filtering is enabled, false otherwise
*
* @see #setTextFilterEnabled(boolean)
* @see Filterable
*/
@ViewDebug.ExportedProperty
public boolean isTextFilterEnabled() {
return mTextFilterEnabled;
}
@Override
public void getFocusedRect(Rect r) {
View view = getSelectedView();
if (view != null && view.getParent() == this) {
// the focused rectangle of the selected view offset into the
// coordinate space of this view.
view.getFocusedRect(r);
offsetDescendantRectToMyCoords(view, r);
} else {
// otherwise, just the norm
super.getFocusedRect(r);
}
}
private void useDefaultSelector() {
setSelector(getResources().getDrawable(
android.R.drawable.list_selector_background));
}
/**
* Indicates whether the content of this view is pinned to, or stacked from,
* the bottom edge.
*
* @return true if the content is stacked from the bottom edge, false
* otherwise
*/
@ViewDebug.ExportedProperty
public boolean isStackFromBottom() {
return mStackFromBottom;
}
/**
* When stack from bottom is set to true, the list fills its content
* starting from the bottom of the view.
*
* @param stackFromBottom
* true to pin the view's content to the bottom edge, false to
* pin the view's content to the top edge
*/
public void setStackFromBottom(boolean stackFromBottom) {
if (mStackFromBottom != stackFromBottom) {
mStackFromBottom = stackFromBottom;
requestLayoutIfNecessary();
}
}
void requestLayoutIfNecessary() {
if (getChildCount() > 0) {
resetList();
requestLayout();
invalidate();
}
}
static class SavedState extends BaseSavedState {
long selectedId;
long firstId;
int viewTop;
int position;
int height;
String filter;
/**
* Constructor called from {@link AbsListView#onSaveInstanceState()}
*/
SavedState(Parcelable superState) {
super(superState);
}
/**
* Constructor called from {@link #CREATOR}
*/
private SavedState(Parcel in) {
super(in);
selectedId = in.readLong();
firstId = in.readLong();
viewTop = in.readInt();
position = in.readInt();
height = in.readInt();
filter = in.readString();
}
@Override
public void writeToParcel(Parcel out, int flags) {
super.writeToParcel(out, flags);
out.writeLong(selectedId);
out.writeLong(firstId);
out.writeInt(viewTop);
out.writeInt(position);
out.writeInt(height);
out.writeString(filter);
}
@Override
public String toString() {
return "AbsListView.SavedState{" + Integer.toHexString(System.identityHashCode(this))
+ " selectedId=" + selectedId + " firstId=" + firstId + " viewTop=" + viewTop
+ " position=" + position + " height=" + height + " filter=" + filter + "}";
}
public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() {
public SavedState createFromParcel(Parcel in) {
return new SavedState(in);
}
public SavedState[] newArray(int size) {
return new SavedState[size];
}
};
}
@Override
public Parcelable onSaveInstanceState() {
/*
* This doesn't really make sense as the place to dismiss the popups,
* but there don't seem to be any other useful hooks that happen early
* enough to keep from getting complaints about having leaked the
* window.
*/
dismissPopup();
Parcelable superState = super.onSaveInstanceState();
SavedState ss = new SavedState(superState);
boolean haveChildren = getChildCount() > 0;
long selectedId = getSelectedItemId();
ss.selectedId = selectedId;
ss.height = getHeight();
if (selectedId >= 0) {
// Remember the selection
ss.viewTop = mSelectedTop;
ss.position = getSelectedItemPosition();
ss.firstId = INVALID_POSITION;
} else {
if (haveChildren) {
// Remember the position of the first child
View v = getChildAt(0);
ss.viewTop = v.getTop();
ss.position = mFirstPosition;
ss.firstId = mAdapter.getItemId(mFirstPosition);
} else {
ss.viewTop = 0;
ss.firstId = INVALID_POSITION;
ss.position = 0;
}
}
ss.filter = null;
if (mFiltered) {
// final EditText textFilter = mTextFilter;
// if (textFilter != null) {
// Editable filterText = textFilter.getText();
// if (filterText != null) {
// ss.filter = filterText.toString();
// }
// }
}
return ss;
}
@Override
public void onRestoreInstanceState(Parcelable state) {
SavedState ss = (SavedState) state;
super.onRestoreInstanceState(ss.getSuperState());
mDataChanged = true;
mSyncHeight = ss.height;
if (ss.selectedId >= 0) {
mNeedSync = true;
mSyncRowId = ss.selectedId;
mSyncPosition = ss.position;
mSpecificTop = ss.viewTop;
mSyncMode = SYNC_SELECTED_POSITION;
} else if (ss.firstId >= 0) {
setSelectedPositionInt(INVALID_POSITION);
// Do this before setting mNeedSync since setNextSelectedPosition
// looks at mNeedSync
setNextSelectedPositionInt(INVALID_POSITION);
mNeedSync = true;
mSyncRowId = ss.firstId;
mSyncPosition = ss.position;
mSpecificTop = ss.viewTop;
mSyncMode = SYNC_FIRST_POSITION;
}
requestLayout();
}
@Override
protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) {
super.onFocusChanged(gainFocus, direction, previouslyFocusedRect);
if (gainFocus && mSelectedPosition < 0 && !isInTouchMode()) {
resurrectSelection();
}
}
@Override
public void requestLayout() {
if (!mBlockLayoutRequests && !mInLayout) {
super.requestLayout();
}
}
/**
* The list is empty. Clear everything out.
*/
void resetList() {
removeAllViewsInLayout();
mFirstPosition = 0;
mDataChanged = false;
mNeedSync = false;
mOldSelectedPosition = INVALID_POSITION;
mOldSelectedRowId = INVALID_ROW_ID;
setSelectedPositionInt(INVALID_POSITION);
setNextSelectedPositionInt(INVALID_POSITION);
mSelectedTop = 0;
mSelectorRect.setEmpty();
invalidate();
}
@Override
protected int computeVerticalScrollExtent() {
final int count = getChildCount();
if (count > 0) {
if (mSmoothScrollbarEnabled) {
int extent = count * 100;
View view = getChildAt(0);
final int top = view.getTop();
int height = view.getHeight();
if (height > 0) {
extent += (top * 100) / height;
}
view = getChildAt(count - 1);
final int bottom = view.getBottom();
height = view.getHeight();
if (height > 0) {
extent -= ((bottom - getHeight()) * 100) / height;
}
return extent;
} else {
return 1;
}
}
return 0;
}
@Override
protected int computeVerticalScrollOffset() {
final int firstPosition = mFirstPosition;
final int childCount = getChildCount();
if (firstPosition >= 0 && childCount > 0) {
if (mSmoothScrollbarEnabled) {
final View view = getChildAt(0);
final int top = view.getTop();
int height = view.getHeight();
if (height > 0) {
return Math.max(firstPosition * 100 - (top * 100) / height
+ (int) ((float) getScrollY() / getHeight() * mItemCount * 100), 0);
}
} else {
int index;
final int count = mItemCount;
if (firstPosition == 0) {
index = 0;
} else if (firstPosition + childCount == count) {
index = count;
} else {
index = firstPosition + childCount / 2;
}
return (int) (firstPosition + childCount * (index / (float) count));
}
}
return 0;
}
@Override
protected int computeVerticalScrollRange() {
int result;
if (mSmoothScrollbarEnabled) {
result = Math.max(mItemCount * 100, 0);
} else {
result = mItemCount;
}
return result;
}
@Override
protected float getTopFadingEdgeStrength() {
final int count = getChildCount();
final float fadeEdge = super.getTopFadingEdgeStrength();
if (count == 0) {
return fadeEdge;
} else {
if (mFirstPosition > 0) {
return 1.0f;
}
final int top = getChildAt(0).getTop();
final float fadeLength = (float) getVerticalFadingEdgeLength();
return top < getPaddingTop() ? (float) -(top - getPaddingTop()) / fadeLength : fadeEdge;
}
}
@Override
protected float getBottomFadingEdgeStrength() {
final int count = getChildCount();
final float fadeEdge = super.getBottomFadingEdgeStrength();
if (count == 0) {
return fadeEdge;
} else {
if (mFirstPosition + count - 1 < mItemCount - 1) {
return 1.0f;
}
final int bottom = getChildAt(count - 1).getBottom();
final int height = getHeight();
final float fadeLength = (float) getVerticalFadingEdgeLength();
return bottom > height - getPaddingBottom() ? (float) (bottom - height + getPaddingBottom())
/ fadeLength : fadeEdge;
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mSelector == null) {
useDefaultSelector();
}
final Rect listPadding = mListPadding;
listPadding.left = mSelectionLeftPadding + getPaddingLeft();
listPadding.top = mSelectionTopPadding + getPaddingTop();
listPadding.right = mSelectionRightPadding + getPaddingRight();
listPadding.bottom = mSelectionBottomPadding + getPaddingBottom();
}
/**
* Subclasses should NOT override this method but {@link #layoutChildren()}
* instead.
*/
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
mInLayout = true;
// Log.d("TAG", "layout changed " + changed);
if (changed) {
int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
getChildAt(i).forceLayout();
}
mRecycler.markChildrenDirty();
}
layoutChildren();
mInLayout = false;
}
/**
* Subclasses must override this method to layout their children.
*/
protected void layoutChildren() {
}
void updateScrollIndicators() {
if (mScrollUp != null) {
boolean canScrollUp;
// 0th element is not visible
canScrollUp = mFirstPosition > 0;
// ... Or top of 0th element is not visible
if (!canScrollUp) {
if (getChildCount() > 0) {
View child = getChildAt(0);
canScrollUp = child.getTop() < mListPadding.top;
}
}
mScrollUp.setVisibility(canScrollUp ? View.VISIBLE : View.INVISIBLE);
}
if (mScrollDown != null) {
boolean canScrollDown;
int count = getChildCount();
// Last item is not visible
canScrollDown = (mFirstPosition + count) < mItemCount;
// ... Or bottom of the last element is not visible
if (!canScrollDown && count > 0) {
View child = getChildAt(count - 1);
canScrollDown = child.getBottom() > getBottom() - mListPadding.bottom;
}
mScrollDown.setVisibility(canScrollDown ? View.VISIBLE : View.INVISIBLE);
}
}
@Override
@ViewDebug.ExportedProperty
public View getSelectedView() {
if (mItemCount > 0 && mSelectedPosition >= 0) {
return getChildAt(mSelectedPosition - mFirstPosition);
} else {
return null;
}
}
/**
* List padding is the maximum of the normal view's padding and the padding
* of the selector.
*
* @see android.view.View#getPaddingTop()
* @see #getSelector()
*
* @return The top list padding.
*/
public int getListPaddingTop() {
return mListPadding.top;
}
/**
* List padding is the maximum of the normal view's padding and the padding
* of the selector.
*
* @see android.view.View#getPaddingBottom()
* @see #getSelector()
*
* @return The bottom list padding.
*/
public int getListPaddingBottom() {
return mListPadding.bottom;
}
/**
* List padding is the maximum of the normal view's padding and the padding
* of the selector.
*
* @see android.view.View#getPaddingLeft()
* @see #getSelector()
*
* @return The left list padding.
*/
public int getListPaddingLeft() {
return mListPadding.left;
}
/**
* List padding is the maximum of the normal view's padding and the padding
* of the selector.
*
* @see android.view.View#getPaddingRight()
* @see #getSelector()
*
* @return The right list padding.
*/
public int getListPaddingRight() {
return mListPadding.right;
}
/**
* Get a view and have it show the data associated with the specified
* position. This is called when we have already discovered that the view is
* not available for reuse in the recycle bin. The only choices left are
* converting an old view or making a new one.
*
* @param position
* The position to display
* @param isScrap
* Array of at least 1 boolean, the first entry will become true
* if the returned view was taken from the scrap heap, false if
* otherwise.
*
* @return A view displaying the data associated with the specified position
*/
View obtainView(int position, boolean[] isScrap) {
isScrap[0] = false;
View scrapView;
scrapView = mRecycler.getScrapView(position);
// Log.d("TAG", "obtain the scrap view is " + scrapView);
View child;
if (scrapView != null) {
if (ViewDebug.TRACE_RECYCLER) {
ViewDebug.trace(scrapView, ViewDebug.RecyclerTraceType.RECYCLE_FROM_SCRAP_HEAP,
position, -1);
}
child = mAdapter.getView(position, scrapView, this);
if (ViewDebug.TRACE_RECYCLER) {
ViewDebug.trace(child, ViewDebug.RecyclerTraceType.BIND_VIEW, position,
getChildCount());
}
// Log.d("TAG", "obtain the scrap view child is same with scrap " + (child == scrapView));
if (child != scrapView) {
mRecycler.addScrapView(scrapView);
if (mCacheColorHint != 0) {
child.setDrawingCacheBackgroundColor(mCacheColorHint);
}
if (ViewDebug.TRACE_RECYCLER) {
ViewDebug.trace(scrapView, ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP,
position, -1);
}
} else {
isScrap[0] = true;
dispatchFinishTemporaryDetach(child);
}
} else {
child = mAdapter.getView(position, null, this);
if (mCacheColorHint != 0) {
child.setDrawingCacheBackgroundColor(mCacheColorHint);
}
if (ViewDebug.TRACE_RECYCLER) {
ViewDebug.trace(child, ViewDebug.RecyclerTraceType.NEW_VIEW, position,
getChildCount());
}
}
// Log.d("TAG", "mIsScrap 0 in obtainView is " + isScrap[0]);
return child;
}
private void dispatchFinishTemporaryDetach(View v) {
if( v == null )
return;
v.onFinishTemporaryDetach();
if( v instanceof ViewGroup){
ViewGroup group = (ViewGroup) v;
final int count = group.getChildCount();
for (int i = 0; i < count; i++) {
dispatchFinishTemporaryDetach(group.getChildAt(i));
}
}
}
void positionSelector(View sel) {
final Rect selectorRect = mSelectorRect;
selectorRect.set(sel.getLeft(), sel.getTop(), sel.getRight(), sel.getBottom());
positionSelector(selectorRect.left, selectorRect.top, selectorRect.right,
selectorRect.bottom);
final boolean isChildViewEnabled = mIsChildViewEnabled;
if (sel.isEnabled() != isChildViewEnabled) {
mIsChildViewEnabled = !isChildViewEnabled;
refreshDrawableState();
}
}
private void positionSelector(int l, int t, int r, int b) {
mSelectorRect.set(l - mSelectionLeftPadding, t - mSelectionTopPadding, r
+ mSelectionRightPadding, b + mSelectionBottomPadding);
}
@Override
protected void dispatchDraw(Canvas canvas) {
final boolean drawSelectorOnTop = mDrawSelectorOnTop;
if (!drawSelectorOnTop) {
drawSelector(canvas);
}
super.dispatchDraw(canvas);
if (drawSelectorOnTop) {
drawSelector(canvas);
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
if (getChildCount() > 0) {
mDataChanged = true;
rememberSyncState();
}
}
/**
* @return True if the current touch mode requires that we draw the selector
* in the pressed state.
*/
boolean touchModeDrawsInPressedState() {
// FIXME use isPressed for this
switch (mTouchMode) {
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
return true;
default:
return false;
}
}
/**
* Indicates whether this view is in a state where the selector should be
* drawn. This will happen if we have focus but are not in touch mode, or we
* are in the middle of displaying the pressed state for an item.
*
* @return True if the selector should be shown
*/
boolean shouldShowSelector() {
return (hasFocus() && !isInTouchMode()) || touchModeDrawsInPressedState();
}
private void drawSelector(Canvas canvas) {
if (shouldShowSelector() && mSelectorRect != null && !mSelectorRect.isEmpty()) {
final Drawable selector = mSelector;
selector.setBounds(mSelectorRect);
selector.draw(canvas);
}
}
/**
* Controls whether the selection highlight drawable should be drawn on top
* of the item or behind it.
*
* @param onTop
* If true, the selector will be drawn on the item it is
* highlighting. The default is false.
*
* @attr ref android.R.styleable#AbsListView_drawSelectorOnTop
*/
public void setDrawSelectorOnTop(boolean onTop) {
mDrawSelectorOnTop = onTop;
}
/**
* Set a Drawable that should be used to highlight the currently selected
* item.
*
* @param resID
* A Drawable resource to use as the selection highlight.
*
* @attr ref android.R.styleable#AbsListView_listSelector
*/
public void setSelector(int resID) {
setSelector(getResources().getDrawable(resID));
}
public void setSelector(Drawable sel) {
if (mSelector != null) {
mSelector.setCallback(null);
unscheduleDrawable(mSelector);
}
mSelector = sel;
Rect padding = new Rect();
sel.getPadding(padding);
mSelectionLeftPadding = padding.left;
mSelectionTopPadding = padding.top;
mSelectionRightPadding = padding.right;
mSelectionBottomPadding = padding.bottom;
sel.setCallback(this);
sel.setState(getDrawableState());
}
/**
* Returns the selector {@link android.graphics.drawable.Drawable} that is
* used to draw the selection in the list.
*
* @return the drawable used to display the selector
*/
public Drawable getSelector() {
return mSelector;
}
/**
* Sets the selector state to "pressed" and posts a CheckForKeyLongPress to
* see if this is a long press.
*/
void keyPressed() {
if (!isEnabled() || !isClickable()) {
return;
}
Drawable selector = mSelector;
Rect selectorRect = mSelectorRect;
if (selector != null && (isFocused() || touchModeDrawsInPressedState())
&& selectorRect != null && !selectorRect.isEmpty()) {
final View v = getChildAt(mSelectedPosition - mFirstPosition);
if (v != null) {
if (v.hasFocusable())
return;
v.setPressed(true);
}
setPressed(true);
final boolean longClickable = isLongClickable();
Drawable d = selector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
if (longClickable) {
((TransitionDrawable) d).startTransition(ViewConfiguration
.getLongPressTimeout());
} else {
((TransitionDrawable) d).resetTransition();
}
}
if (longClickable && !mDataChanged) {
if (mPendingCheckForKeyLongPress == null) {
mPendingCheckForKeyLongPress = new CheckForKeyLongPress();
}
mPendingCheckForKeyLongPress.rememberWindowAttachCount();
postDelayed(mPendingCheckForKeyLongPress, ViewConfiguration.getLongPressTimeout());
}
}
}
public void setScrollIndicators(View up, View down) {
mScrollUp = up;
mScrollDown = down;
}
@Override
protected void drawableStateChanged() {
super.drawableStateChanged();
if (mSelector != null) {
mSelector.setState(getDrawableState());
}
}
@Override
protected int[] onCreateDrawableState(int extraSpace) {
// If the child view is enabled then do the default behavior.
if (mIsChildViewEnabled) {
// Common case
return super.onCreateDrawableState(extraSpace);
}
// The selector uses this View's drawable state. The selected child view
// is disabled, so we need to remove the enabled state from the drawable
// states.
final int enabledState = ENABLED_STATE_SET[0];
// If we don't have any extra space, it will return one of the static
// state arrays,
// and clearing the enabled state on those arrays is a bad thing! If we
// specify
// we need extra space, it will create+copy into a new array that safely
// mutable.
int[] state = super.onCreateDrawableState(extraSpace + 1);
int enabledPos = -1;
for (int i = state.length - 1; i >= 0; i--) {
if (state[i] == enabledState) {
enabledPos = i;
break;
}
}
// Remove the enabled state
if (enabledPos >= 0) {
System.arraycopy(state, enabledPos + 1, state, enabledPos, state.length - enabledPos
- 1);
}
return state;
}
@Override
public boolean verifyDrawable(Drawable dr) {
return mSelector == dr || super.verifyDrawable(dr);
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
final ViewTreeObserver treeObserver = getViewTreeObserver();
if (treeObserver != null) {
treeObserver.addOnTouchModeChangeListener(this);
if (mTextFilterEnabled && mPopup != null && !mGlobalLayoutListenerAddedFilter) {
treeObserver.addOnGlobalLayoutListener(this);
}
}
}
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
// Dismiss the popup in case onSaveInstanceState() was not invoked
dismissPopup();
// Detach any view left in the scrap heap
mRecycler.clear();
final ViewTreeObserver treeObserver = getViewTreeObserver();
if (treeObserver != null) {
treeObserver.removeOnTouchModeChangeListener(this);
if (mTextFilterEnabled && mPopup != null) {
treeObserver.removeGlobalOnLayoutListener(this);
mGlobalLayoutListenerAddedFilter = false;
}
}
}
@Override
public void onWindowFocusChanged(boolean hasWindowFocus) {
super.onWindowFocusChanged(hasWindowFocus);
final int touchMode = isInTouchMode() ? TOUCH_MODE_ON : TOUCH_MODE_OFF;
if (!hasWindowFocus) {
setChildrenDrawingCacheEnabled(false);
if (mFlingRunnable != null) {
removeCallbacks(mFlingRunnable);
// let the fling runnable report it's new state which
// should be idle
mFlingRunnable.endFling();
if (getScaleY() != 0) {
// mScrollY = 0;
scrollTo(getScrollX(), 0);
invalidate();
}
}
// Always hide the type filter
dismissPopup();
if (touchMode == TOUCH_MODE_OFF) {
// Remember the last selected element
mResurrectToPosition = mSelectedPosition;
}
} else {
if (mFiltered && !mPopupHidden) {
// Show the type filter only if a filter is in effect
showPopup();
}
// If we changed touch mode since the last time we had focus
if (touchMode != mLastTouchMode && mLastTouchMode != TOUCH_MODE_UNKNOWN) {
// If we come back in trackball mode, we bring the selection
// back
if (touchMode == TOUCH_MODE_OFF) {
// This will trigger a layout
resurrectSelection();
// If we come back in touch mode, then we want to hide the
// selector
} else {
hideSelector();
mLayoutMode = LAYOUT_NORMAL;
layoutChildren();
}
}
}
mLastTouchMode = touchMode;
}
/**
* Creates the ContextMenuInfo returned from {@link #getContextMenuInfo()}.
* This methods knows the view, position and ID of the item that received
* the long press.
*
* @param view
* The view that received the long press.
* @param position
* The position of the item that received the long press.
* @param id
* The ID of the item that received the long press.
* @return The extra information that should be returned by
* {@link #getContextMenuInfo()}.
*/
ContextMenuInfo createContextMenuInfo(View view, int position, long id) {
return new AdapterContextMenuInfo(view, position, id);
}
/**
* A base class for Runnables that will check that their view is still
* attached to the original window as when the Runnable was created.
*
*/
private class WindowRunnnable {
private int mOriginalAttachCount;
public void rememberWindowAttachCount() {
mOriginalAttachCount = getWindowAttachCount();
}
public boolean sameWindow() {
return hasWindowFocus() && getWindowAttachCount() == mOriginalAttachCount;
}
}
private class PerformClick extends WindowRunnnable implements Runnable {
View mChild;
int mClickMotionPosition;
public void run() {
// The data has changed since we posted this action in the event
// queue,
// bail out before bad things happen
if (mDataChanged)
return;
final ListAdapter adapter = mAdapter;
final int motionPosition = mClickMotionPosition;
if (adapter != null && mItemCount > 0 && motionPosition != INVALID_POSITION
&& motionPosition < adapter.getCount() && sameWindow()) {
performItemClick(mChild, motionPosition, adapter.getItemId(motionPosition));
}
}
}
private class CheckForLongPress extends WindowRunnnable implements Runnable {
public void run() {
final int motionPosition = mMotionPosition;
final View child = getChildAt(motionPosition - mFirstPosition);
if (child != null) {
final int longPressPosition = mMotionPosition;
final long longPressId = mAdapter.getItemId(mMotionPosition);
boolean handled = false;
if (sameWindow() && !mDataChanged) {
handled = performLongPress(child, longPressPosition, longPressId);
}
if (handled) {
mTouchMode = TOUCH_MODE_REST;
setPressed(false);
child.setPressed(false);
} else {
mTouchMode = TOUCH_MODE_DONE_WAITING;
}
}
}
}
private class CheckForKeyLongPress extends WindowRunnnable implements Runnable {
public void run() {
if (isPressed() && mSelectedPosition >= 0) {
int index = mSelectedPosition - mFirstPosition;
View v = getChildAt(index);
if (!mDataChanged) {
boolean handled = false;
if (sameWindow()) {
handled = performLongPress(v, mSelectedPosition, mSelectedRowId);
}
if (handled) {
setPressed(false);
v.setPressed(false);
}
} else {
setPressed(false);
if (v != null)
v.setPressed(false);
}
}
}
}
private boolean performLongPress(final View child, final int longPressPosition,
final long longPressId) {
boolean handled = false;
if (mOnItemLongClickListener != null) {
handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, child,
longPressPosition, longPressId);
}
if (!handled) {
mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId);
handled = super.showContextMenuForChild(AbsListView.this);
}
if (handled) {
performHapticFeedback(HapticFeedbackConstants.LONG_PRESS);
}
return handled;
}
@Override
protected ContextMenuInfo getContextMenuInfo() {
return mContextMenuInfo;
}
@Override
public boolean showContextMenuForChild(View originalView) {
final int longPressPosition = getPositionForView(originalView);
if (longPressPosition >= 0) {
final long longPressId = mAdapter.getItemId(longPressPosition);
boolean handled = false;
if (mOnItemLongClickListener != null) {
handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, originalView,
longPressPosition, longPressId);
}
if (!handled) {
mContextMenuInfo = createContextMenuInfo(getChildAt(longPressPosition
- mFirstPosition), longPressPosition, longPressId);
handled = super.showContextMenuForChild(originalView);
}
return handled;
}
return false;
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
return false;
}
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_CENTER:
case KeyEvent.KEYCODE_ENTER:
if (!isEnabled()) {
return true;
}
if (isClickable() && isPressed() && mSelectedPosition >= 0 && mAdapter != null
&& mSelectedPosition < mAdapter.getCount()) {
final View view = getChildAt(mSelectedPosition - mFirstPosition);
if (view != null) {
performItemClick(view, mSelectedPosition, mSelectedRowId);
view.setPressed(false);
}
setPressed(false);
return true;
}
break;
}
return super.onKeyUp(keyCode, event);
}
@Override
protected void dispatchSetPressed(boolean pressed) {
// Don't dispatch setPressed to our children. We call setPressed on
// ourselves to
// get the selector in the right state, but we don't want to press each
// child.
}
/**
* Maps a point to a position in the list.
*
* @param x
* X in local coordinate
* @param y
* Y in local coordinate
* @return The position of the item which contains the specified point, or
* {@link #INVALID_POSITION} if the point does not intersect an
* item.
*/
public int pointToPosition(int x, int y) {
Rect frame = mTouchFrame;
if (frame == null) {
mTouchFrame = new Rect();
frame = mTouchFrame;
}
final int count = getChildCount();
for (int i = count - 1; i >= 0; i--) {
final View child = getChildAt(i);
if (child.getVisibility() == View.VISIBLE) {
child.getHitRect(frame);
if (frame.contains(x, y)) {
return mFirstPosition + i;
}
}
}
return INVALID_POSITION;
}
/**
* Maps a point to a the rowId of the item which intersects that point.
*
* @param x
* X in local coordinate
* @param y
* Y in local coordinate
* @return The rowId of the item which contains the specified point, or
* {@link #INVALID_ROW_ID} if the point does not intersect an item.
*/
public long pointToRowId(int x, int y) {
int position = pointToPosition(x, y);
if (position >= 0) {
return mAdapter.getItemId(position);
}
return INVALID_ROW_ID;
}
final class CheckForTap implements Runnable {
public void run() {
if (mTouchMode == TOUCH_MODE_DOWN) {
mTouchMode = TOUCH_MODE_TAP;
final View child = getChildAt(mMotionPosition - mFirstPosition);
if (child != null && !child.hasFocusable()) {
mLayoutMode = LAYOUT_NORMAL;
if (!mDataChanged) {
layoutChildren();
child.setPressed(true);
positionSelector(child);
setPressed(true);
final int longPressTimeout = ViewConfiguration.getLongPressTimeout();
final boolean longClickable = isLongClickable();
if (mSelector != null) {
Drawable d = mSelector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
if (longClickable) {
((TransitionDrawable) d).startTransition(longPressTimeout);
} else {
((TransitionDrawable) d).resetTransition();
}
}
}
if (longClickable) {
if (mPendingCheckForLongPress == null) {
mPendingCheckForLongPress = new CheckForLongPress();
}
mPendingCheckForLongPress.rememberWindowAttachCount();
postDelayed(mPendingCheckForLongPress, longPressTimeout);
} else {
mTouchMode = TOUCH_MODE_DONE_WAITING;
}
} else {
mTouchMode = TOUCH_MODE_DONE_WAITING;
}
}
}
}
}
private boolean startScrollIfNeeded(int deltaY) {
// Check if we have moved far enough that it looks more like a
// scroll than a tap
final int distance = Math.abs(deltaY);
if (distance > mTouchSlop) {
createScrollingCache();
mTouchMode = TOUCH_MODE_SCROLL;
mMotionCorrection = deltaY;
final Handler handler = getHandler();
// Handler should not be null unless the AbsListView is not attached
// to a
// window, which would make it very hard to scroll it... but the
// monkeys
// say it's possible.
if (handler != null) {
handler.removeCallbacks(mPendingCheckForLongPress);
}
setPressed(false);
View motionView = getChildAt(mMotionPosition - mFirstPosition);
if (motionView != null) {
motionView.setPressed(false);
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL);
// Time to start stealing events! Once we've stolen them, don't let
// anyone
// steal from us
requestDisallowInterceptTouchEvent(true);
return true;
}
return false;
}
public void onTouchModeChanged(boolean isInTouchMode) {
if (isInTouchMode) {
// Get rid of the selection when we enter touch mode
hideSelector();
// Layout, but only if we already have done so previously.
// (Otherwise may clobber a LAYOUT_SYNC layout that was requested to
// restore
// state.)
if (getHeight() > 0 && getChildCount() > 0) {
// We do not lose focus initiating a touch (since AbsListView is
// focusable in
// touch mode). Force an initial layout to get rid of the
// selection.
layoutChildren();
}
}
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (!isEnabled()) {
// A disabled view that is clickable still consumes the touch
// events, it just doesn't respond to them.
return isClickable() || isLongClickable();
}
final int action = ev.getAction();
View v;
int deltaY;
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
}
mVelocityTracker.addMovement(ev);
switch (action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN: {
mActivePointerId = ev.getPointerId(0);
final int x = (int) ev.getX();
final int y = (int) ev.getY();
int motionPosition = pointToPosition(x, y);
if (!mDataChanged) {
if ((mTouchMode != TOUCH_MODE_FLING) && (motionPosition >= 0)
&& (getAdapter().isEnabled(motionPosition))) {
// User clicked on an actual view (and was not stopping a
// fling). It might be a
// click or a scroll. Assume it is a click until proven
// otherwise
mTouchMode = TOUCH_MODE_DOWN;
// FIXME Debounce
if (mPendingCheckForTap == null) {
mPendingCheckForTap = new CheckForTap();
}
postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout());
} else {
if (ev.getEdgeFlags() != 0 && motionPosition < 0) {
// If we couldn't find a view to click on, but the down
// event was touching
// the edge, we will bail out and try again. This allows
// the edge correcting
// code in ViewRoot to try to find a nearby view to
// select
return false;
}
if (mTouchMode == TOUCH_MODE_FLING) {
Log.d("TAG", "touch mode is fling");
// Stopped a fling. It is a scroll.
createScrollingCache();
mTouchMode = TOUCH_MODE_SCROLL;
mMotionCorrection = 0;
motionPosition = findMotionRow(y);
reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL);
trackMotionScroll(1, 1);
}
}
}
if (motionPosition >= 0) {
// Remember where the motion event started
v = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = v.getTop();
}
mMotionX = x;
mMotionY = y;
mMotionPosition = motionPosition;
mLastY = Integer.MIN_VALUE;
break;
}
case MotionEvent.ACTION_MOVE: {
final int pointerIndex = ev.findPointerIndex(mActivePointerId);
final int y = (int) ev.getY(pointerIndex);
deltaY = y - mMotionY;
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
// Check if we have moved far enough that it looks more like a
// scroll than a tap
startScrollIfNeeded(deltaY);
break;
case TOUCH_MODE_SCROLL:
if (PROFILE_SCROLLING) {
if (!mScrollProfilingStarted) {
Debug.startMethodTracing("AbsListViewScroll");
mScrollProfilingStarted = true;
}
}
if (y != mLastY) {
deltaY -= mMotionCorrection;
int incrementalDeltaY = mLastY != Integer.MIN_VALUE ? y - mLastY : deltaY;
// No need to do all this work if we're not going to move
// anyway
boolean atEdge = false;
if (incrementalDeltaY != 0) {
atEdge = trackMotionScroll(deltaY, incrementalDeltaY);
}
// Check to see if we have bumped into the scroll limit
if (atEdge && getChildCount() > 0) {
// Treat this like we're starting a new scroll from the
// current
// position. This will let the user start scrolling back
// into
// content immediately rather than needing to scroll
// back to the
// point where they hit the limit first.
int motionPosition = findMotionRow(y);
if (motionPosition >= 0) {
final View motionView = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = motionView.getTop();
}
mMotionY = y;
mMotionPosition = motionPosition;
invalidate();
}
mLastY = y;
}
break;
}
break;
}
case MotionEvent.ACTION_UP: {
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
final int motionPosition = mMotionPosition;
final View child = getChildAt(motionPosition - mFirstPosition);
if (child != null && !child.hasFocusable()) {
if (mTouchMode != TOUCH_MODE_DOWN) {
child.setPressed(false);
}
if (mPerformClick == null) {
mPerformClick = new PerformClick();
}
final AbsListView.PerformClick performClick = mPerformClick;
performClick.mChild = child;
performClick.mClickMotionPosition = motionPosition;
performClick.rememberWindowAttachCount();
mResurrectToPosition = motionPosition;
if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) {
final Handler handler = getHandler();
if (handler != null) {
handler.removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? mPendingCheckForTap
: mPendingCheckForLongPress);
}
mLayoutMode = LAYOUT_NORMAL;
if (!mDataChanged && mAdapter.isEnabled(motionPosition)) {
mTouchMode = TOUCH_MODE_TAP;
setSelectedPositionInt(mMotionPosition);
layoutChildren();
child.setPressed(true);
positionSelector(child);
setPressed(true);
if (mSelector != null) {
Drawable d = mSelector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
((TransitionDrawable) d).resetTransition();
}
}
postDelayed(new Runnable() {
public void run() {
child.setPressed(false);
setPressed(false);
if (!mDataChanged) {
post(performClick);
}
mTouchMode = TOUCH_MODE_REST;
}
}, ViewConfiguration.getPressedStateDuration());
} else {
mTouchMode = TOUCH_MODE_REST;
}
return true;
} else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) {
post(performClick);
}
}
mTouchMode = TOUCH_MODE_REST;
break;
case TOUCH_MODE_SCROLL:
final int childCount = getChildCount();
if (childCount > 0) {
if (mFirstPosition == 0
&& getChildAt(0).getTop() >= mListPadding.top
&& mFirstPosition + childCount < mItemCount
&& getChildAt(childCount - 1).getBottom() <= getHeight()
- mListPadding.bottom) {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
} else {
final VelocityTracker velocityTracker = mVelocityTracker;
velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
final int initialVelocity = (int) velocityTracker
.getYVelocity(mActivePointerId);
if (Math.abs(initialVelocity) > mMinimumVelocity) {
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
mFlingRunnable.start(-initialVelocity);
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
}
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
break;
}
setPressed(false);
// Need to redraw since we probably aren't drawing the selector
// anymore
invalidate();
final Handler handler = getHandler();
if (handler != null) {
handler.removeCallbacks(mPendingCheckForLongPress);
}
if (mVelocityTracker != null) {
mVelocityTracker.recycle();
mVelocityTracker = null;
}
mActivePointerId = INVALID_POINTER;
if (PROFILE_SCROLLING) {
if (mScrollProfilingStarted) {
Debug.stopMethodTracing();
mScrollProfilingStarted = false;
}
}
break;
}
case MotionEvent.ACTION_CANCEL: {
mTouchMode = TOUCH_MODE_REST;
setPressed(false);
View motionView = this.getChildAt(mMotionPosition - mFirstPosition);
if (motionView != null) {
motionView.setPressed(false);
}
clearScrollingCache();
final Handler handler = getHandler();
if (handler != null) {
handler.removeCallbacks(mPendingCheckForLongPress);
}
if (mVelocityTracker != null) {
mVelocityTracker.recycle();
mVelocityTracker = null;
}
mActivePointerId = INVALID_POINTER;
break;
}
case MotionEvent.ACTION_POINTER_UP: {
onSecondaryPointerUp(ev);
final int x = mMotionX;
final int y = mMotionY;
final int motionPosition = pointToPosition(x, y);
if (motionPosition >= 0) {
// Remember where the motion event started
v = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = v.getTop();
mMotionPosition = motionPosition;
}
mLastY = y;
break;
}
}
return true;
}
@Override
public void draw(Canvas canvas) {
super.draw(canvas);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
int action = ev.getAction();
View v;
switch (action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN: {
int touchMode = mTouchMode;
final int x = (int) ev.getX();
final int y = (int) ev.getY();
mActivePointerId = ev.getPointerId(0);
int motionPosition = findMotionRow(y);
if (touchMode != TOUCH_MODE_FLING && motionPosition >= 0) {
// User clicked on an actual view (and was not stopping a
// fling).
// Remember where the motion event started
v = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = v.getTop();
mMotionX = x;
mMotionY = y;
mMotionPosition = motionPosition;
mTouchMode = TOUCH_MODE_DOWN;
clearScrollingCache();
}
mLastY = Integer.MIN_VALUE;
if (touchMode == TOUCH_MODE_FLING) {
return true;
}
break;
}
case MotionEvent.ACTION_MOVE: {
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
final int pointerIndex = ev.findPointerIndex(mActivePointerId);
final int y = (int) ev.getY(pointerIndex);
if (startScrollIfNeeded(y - mMotionY)) {
return true;
}
break;
}
break;
}
case MotionEvent.ACTION_UP: {
mTouchMode = TOUCH_MODE_REST;
mActivePointerId = INVALID_POINTER;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
break;
}
case MotionEvent.ACTION_POINTER_UP: {
onSecondaryPointerUp(ev);
break;
}
}
return false;
}
private void onSecondaryPointerUp(MotionEvent ev) {
final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;
final int pointerId = ev.getPointerId(pointerIndex);
if (pointerId == mActivePointerId) {
// This was our active pointer going up. Choose a new
// active pointer and adjust accordingly.
// TODO: Make this decision more intelligent.
final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
mMotionX = (int) ev.getX(newPointerIndex);
mMotionY = (int) ev.getY(newPointerIndex);
mActivePointerId = ev.getPointerId(newPointerIndex);
if (mVelocityTracker != null) {
mVelocityTracker.clear();
}
}
}
/**
* {@inheritDoc}
*/
@Override
public void addTouchables(ArrayList<View> views) {
final int count = getChildCount();
final int firstPosition = mFirstPosition;
final ListAdapter adapter = mAdapter;
if (adapter == null) {
return;
}
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (adapter.isEnabled(firstPosition + i)) {
views.add(child);
}
child.addTouchables(views);
}
}
/**
* Fires an "on scroll state changed" event to the registered
* {@link android.widget.AbsListView.OnScrollListener}, if any. The state
* change is fired only if the specified state is different from the
* previously known state.
*
* @param newState
* The new scroll state.
*/
void reportScrollStateChange(int newState) {
if (newState != mLastScrollState) {
if (mOnScrollListener != null) {
mOnScrollListener.onScrollStateChanged(this, newState);
mLastScrollState = newState;
}
}
}
/**
* Responsible for fling behavior. Use {@link #start(int)} to initiate a
* fling. Each frame of the fling is handled in {@link #run()}. A
* FlingRunnable will keep re-posting itself until the fling is done.
*
*/
private class FlingRunnable implements Runnable {
/**
* Tracks the decay of a fling scroll
*/
private final Scroller mScroller;
/**
* Y value reported by mScroller on the previous fling
*/
private int mLastFlingY;
FlingRunnable() {
mScroller = new Scroller(getContext());
}
void start(int initialVelocity) {
int initialY = initialVelocity < 0 ? Integer.MAX_VALUE : 0;
mLastFlingY = initialY;
mScroller.fling(0, initialY, 0, initialVelocity, 0, Integer.MAX_VALUE, 0,
Integer.MAX_VALUE);
mTouchMode = TOUCH_MODE_FLING;
post(this);
if (PROFILE_FLINGING) {
if (!mFlingProfilingStarted) {
Debug.startMethodTracing("AbsListViewFling");
mFlingProfilingStarted = true;
}
}
}
void startScroll(int distance, int duration) {
int initialY = distance < 0 ? Integer.MAX_VALUE : 0;
mLastFlingY = initialY;
mScroller.startScroll(0, initialY, 0, distance, duration);
mTouchMode = TOUCH_MODE_FLING;
post(this);
}
private void endFling() {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
clearScrollingCache();
removeCallbacks(this);
if (mPositionScroller != null) {
removeCallbacks(mPositionScroller);
}
}
public void run() {
switch (mTouchMode) {
default:
return;
case TOUCH_MODE_FLING: {
if (mItemCount == 0 || getChildCount() == 0) {
endFling();
return;
}
final Scroller scroller = mScroller;
boolean more = scroller.computeScrollOffset();
final int y = scroller.getCurrY();
// Flip sign to convert finger direction to list items direction
// (e.g. finger moving down means list is moving towards the
// top)
int delta = mLastFlingY - y;
// Pretend that each frame of a fling scroll is a touch scroll
if (delta > 0) {
// List is moving towards the top. Use first view as
// mMotionPosition
mMotionPosition = mFirstPosition;
final View firstView = getChildAt(0);
mMotionViewOriginalTop = firstView.getTop();
// Don't fling more than 1 screen
delta = Math.min(getHeight() - getPaddingBottom() - getPaddingTop() - 1, delta);
} else {
// List is moving towards the bottom. Use last view as
// mMotionPosition
int offsetToLast = getChildCount() - 1;
mMotionPosition = mFirstPosition + offsetToLast;
final View lastView = getChildAt(offsetToLast);
mMotionViewOriginalTop = lastView.getTop();
// Don't fling more than 1 screen
delta = Math.max(-(getHeight() - getPaddingBottom() - getPaddingTop() - 1), delta);
}
Log.d("TAG", "fling is running");
final boolean atEnd = trackMotionScroll(delta, delta);
if (more && !atEnd) {
invalidate();
mLastFlingY = y;
post(this);
} else {
Log.d("TAG", "fling is end");
endFling();
if (PROFILE_FLINGING) {
if (mFlingProfilingStarted) {
Debug.stopMethodTracing();
mFlingProfilingStarted = false;
}
}
}
break;
}
}
}
}
class PositionScroller implements Runnable {
private static final int SCROLL_DURATION = 400;
private static final int MOVE_DOWN_POS = 1;
private static final int MOVE_UP_POS = 2;
private static final int MOVE_DOWN_BOUND = 3;
private static final int MOVE_UP_BOUND = 4;
private int mMode;
private int mTargetPos;
private int mBoundPos;
private int mLastSeenPos;
private int mScrollDuration;
private final int mExtraScroll;
PositionScroller() {
mExtraScroll = ViewConfiguration.get(getContext()).getScaledFadingEdgeLength();
}
void start(int position) {
final int firstPos = mFirstPosition;
final int lastPos = firstPos + getChildCount() - 1;
int viewTravelCount = 0;
if (position <= firstPos) {
viewTravelCount = firstPos - position + 1;
mMode = MOVE_UP_POS;
} else if (position >= lastPos) {
viewTravelCount = position - lastPos + 1;
mMode = MOVE_DOWN_POS;
} else {
// Already on screen, nothing to do
return;
}
if (viewTravelCount > 0) {
mScrollDuration = SCROLL_DURATION / viewTravelCount;
} else {
mScrollDuration = SCROLL_DURATION;
}
mTargetPos = position;
mBoundPos = INVALID_POSITION;
mLastSeenPos = INVALID_POSITION;
post(this);
}
void start(int position, int boundPosition) {
if (boundPosition == INVALID_POSITION) {
start(position);
return;
}
final int firstPos = mFirstPosition;
final int lastPos = firstPos + getChildCount() - 1;
int viewTravelCount = 0;
if (position <= firstPos) {
final int boundPosFromLast = lastPos - boundPosition;
if (boundPosFromLast < 1) {
// Moving would shift our bound position off the screen.
// Abort.
return;
}
final int posTravel = firstPos - position + 1;
final int boundTravel = boundPosFromLast - 1;
if (boundTravel < posTravel) {
viewTravelCount = boundTravel;
mMode = MOVE_UP_BOUND;
} else {
viewTravelCount = posTravel;
mMode = MOVE_UP_POS;
}
} else if (position >= lastPos) {
final int boundPosFromFirst = boundPosition - firstPos;
if (boundPosFromFirst < 1) {
// Moving would shift our bound position off the screen.
// Abort.
return;
}
final int posTravel = position - lastPos + 1;
final int boundTravel = boundPosFromFirst - 1;
if (boundTravel < posTravel) {
viewTravelCount = boundTravel;
mMode = MOVE_DOWN_BOUND;
} else {
viewTravelCount = posTravel;
mMode = MOVE_DOWN_POS;
}
} else {
// Already on screen, nothing to do
return;
}
if (viewTravelCount > 0) {
mScrollDuration = SCROLL_DURATION / viewTravelCount;
} else {
mScrollDuration = SCROLL_DURATION;
}
mTargetPos = position;
mBoundPos = boundPosition;
mLastSeenPos = INVALID_POSITION;
post(this);
}
void stop() {
removeCallbacks(this);
}
public void run() {
final int listHeight = getHeight();
final int firstPos = mFirstPosition;
switch (mMode) {
case MOVE_DOWN_POS: {
final int lastViewIndex = getChildCount() - 1;
final int lastPos = firstPos + lastViewIndex;
if (lastViewIndex < 0) {
return;
}
if (lastPos == mLastSeenPos) {
// No new views, let things keep going.
post(this);
return;
}
final View lastView = getChildAt(lastViewIndex);
final int lastViewHeight = lastView.getHeight();
final int lastViewTop = lastView.getTop();
final int lastViewPixelsShowing = listHeight - lastViewTop;
final int extraScroll = lastPos < mItemCount - 1 ? mExtraScroll
: mListPadding.bottom;
smoothScrollBy(lastViewHeight - lastViewPixelsShowing + extraScroll,
mScrollDuration);
mLastSeenPos = lastPos;
if (lastPos < mTargetPos) {
post(this);
}
break;
}
case MOVE_DOWN_BOUND: {
final int nextViewIndex = 1;
final int childCount = getChildCount();
if (firstPos == mBoundPos || childCount <= nextViewIndex
|| firstPos + childCount >= mItemCount) {
return;
}
final int nextPos = firstPos + nextViewIndex;
if (nextPos == mLastSeenPos) {
// No new views, let things keep going.
post(this);
return;
}
final View nextView = getChildAt(nextViewIndex);
final int nextViewHeight = nextView.getHeight();
final int nextViewTop = nextView.getTop();
final int extraScroll = mExtraScroll;
if (nextPos < mBoundPos) {
smoothScrollBy(Math.max(0, nextViewHeight + nextViewTop - extraScroll),
mScrollDuration);
mLastSeenPos = nextPos;
post(this);
} else {
if (nextViewTop > extraScroll) {
smoothScrollBy(nextViewTop - extraScroll, mScrollDuration);
}
}
break;
}
case MOVE_UP_POS: {
if (firstPos == mLastSeenPos) {
// No new views, let things keep going.
post(this);
return;
}
final View firstView = getChildAt(0);
if (firstView == null) {
return;
}
final int firstViewTop = firstView.getTop();
final int extraScroll = firstPos > 0 ? mExtraScroll : mListPadding.top;
smoothScrollBy(firstViewTop - extraScroll, mScrollDuration);
mLastSeenPos = firstPos;
if (firstPos > mTargetPos) {
post(this);
}
break;
}
case MOVE_UP_BOUND: {
final int lastViewIndex = getChildCount() - 2;
if (lastViewIndex < 0) {
return;
}
final int lastPos = firstPos + lastViewIndex;
if (lastPos == mLastSeenPos) {
// No new views, let things keep going.
post(this);
return;
}
final View lastView = getChildAt(lastViewIndex);
final int lastViewHeight = lastView.getHeight();
final int lastViewTop = lastView.getTop();
final int lastViewPixelsShowing = listHeight - lastViewTop;
mLastSeenPos = lastPos;
if (lastPos > mBoundPos) {
smoothScrollBy(-(lastViewPixelsShowing - mExtraScroll), mScrollDuration);
post(this);
} else {
final int bottom = listHeight - mExtraScroll;
final int lastViewBottom = lastViewTop + lastViewHeight;
if (bottom > lastViewBottom) {
smoothScrollBy(-(bottom - lastViewBottom), mScrollDuration);
}
}
break;
}
default:
break;
}
}
}
/**
* 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.
*/
public void smoothScrollToPosition(int position) {
if (mPositionScroller == null) {
mPositionScroller = new PositionScroller();
}
mPositionScroller.start(position);
}
/**
* Smoothly scroll to the specified adapter position. The view will scroll
* such that the indicated position is displayed, but it will stop early if
* scrolling further would scroll boundPosition out of view.
*
* @param position
* Scroll to this adapter position.
* @param boundPosition
* Do not scroll if it would move this adapter position out of
* view.
*/
public void smoothScrollToPosition(int position, int boundPosition) {
if (mPositionScroller == null) {
mPositionScroller = new PositionScroller();
}
mPositionScroller.start(position, boundPosition);
}
/**
* Smoothly scroll by distance pixels over duration milliseconds.
*
* @param distance
* Distance to scroll in pixels.
* @param duration
* Duration of the scroll animation in milliseconds.
*/
public void smoothScrollBy(int distance, int duration) {
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
} else {
mFlingRunnable.endFling();
}
mFlingRunnable.startScroll(distance, duration);
}
private void createScrollingCache() {
if (mScrollingCacheEnabled && !mCachingStarted) {
setChildrenDrawnWithCacheEnabled(true);
setChildrenDrawingCacheEnabled(true);
mCachingStarted = true;
}
}
private void clearScrollingCache() {
if (mClearScrollingCache == null) {
mClearScrollingCache = new Runnable() {
public void run() {
if (mCachingStarted) {
mCachingStarted = false;
setChildrenDrawnWithCacheEnabled(false);
final int mPersistentDrawingCache = getPersistentDrawingCache();
if ((mPersistentDrawingCache & PERSISTENT_SCROLLING_CACHE) == 0) {
setChildrenDrawingCacheEnabled(false);
}
if (!isAlwaysDrawnWithCacheEnabled()) {
invalidate();
}
}
}
};
}
post(mClearScrollingCache);
}
/**
* Track a motion scroll
*
* @param deltaY
* Amount to offset mMotionView. This is the accumulated delta
* since the motion began. Positive numbers mean the user's
* finger is moving down the screen.
* @param incrementalDeltaY
* Change in deltaY from the previous event.
* @return true if we're already at the beginning/end of the list and have
* nothing to do.
*/
boolean trackMotionScroll(int deltaY, int incrementalDeltaY) {
final int childCount = getChildCount();
if (childCount == 0) {
return true;
}
int firstTop = Integer.MIN_VALUE;
int lastBottom = Integer.MAX_VALUE;
int endBottom = Integer.MIN_VALUE;
for (int i = 0; i < mColumnViews.length; i++) {
ArrayList<View> viewList = mColumnViews[i];
int size = viewList.size();
if (size == 0) {
lastBottom = 0;
firstTop = 0;
endBottom = 0;
} else {
int top = viewList.get(0).getTop();
int bottom = viewList.get(size - 1).getBottom();
if (lastBottom > bottom) {
lastBottom = bottom;
}
if (endBottom < bottom) {
endBottom = bottom;
}
if (firstTop < top) {
firstTop = top;
}
}
}
final Rect listPadding = mListPadding;
// FIXME account for grid vertical spacing too?
final int spaceAbove = listPadding.top - firstTop;
final int end = getHeight() - listPadding.bottom;
final int spaceBelow = lastBottom - end;
// Log.d("TAG", "spaceBelow is " + spaceBelow + " , spaceAbove is " + spaceAbove);
final int height = getHeight() - getPaddingBottom() - getPaddingTop();
if (deltaY < 0) {
deltaY = Math.max(-(height - 1), deltaY);
} else {
deltaY = Math.min(height - 1, deltaY);
}
if (incrementalDeltaY < 0) {
incrementalDeltaY = Math.max(-(height - 1), incrementalDeltaY);
} else {
incrementalDeltaY = Math.min(height - 1, incrementalDeltaY);
}
Log.d("TAG", "incrementalDeltaY is " + incrementalDeltaY + " spaceabove is " + spaceAbove + " space below is " + spaceBelow);
final int firstPosition = mFirstPosition;
if (firstPosition == 0 && firstTop >= listPadding.top && deltaY >= 0) {
// Don't need to move views down if the top of the first position
// is already visible
return true;
}
if (firstPosition + childCount == mItemCount && endBottom <= end && deltaY <= 0) {
// Don't need to move views up if the bottom of the last position
// is already visible
// Log.d("TAG", "return last bottom is " + higherBottom + ", end is " + end);
return true;
}
final boolean down = incrementalDeltaY < 0;
final boolean inTouchMode = isInTouchMode();
if (inTouchMode) {
hideSelector();
}
final int headerViewsCount = getHeaderViewsCount();
final int footerViewsStart = mItemCount - getFooterViewsCount();
int start = 0;
int count = 0;
if (down) {
final int top = listPadding.top - incrementalDeltaY;
for (int i = 0; i < childCount; i++) {
final View child = getChildAt(i);
// Log.d("TAG", "scroll down top is " + top + " , view " + i + " bottom is " + child.getBottom());
if (child.getBottom() >= top) {
break;
} else {
count++;
int position = firstPosition + i;
if (position >= headerViewsCount && position < footerViewsStart) {
mRecycler.addScrapView(child);
// Log.d("TAG", "add to scrap view");
int columnIndex = (Integer) child.getTag();
if (columnIndex >= 0 && columnIndex < mColumnCount) {
mColumnViews[columnIndex].remove(child);
}
}
}
}
} else {
final int bottom = getHeight() - listPadding.bottom - incrementalDeltaY;
for (int i = childCount - 1; i >= 0; i--) {
final View child = getChildAt(i);
// Log.d("TAG", "scroll down bottom is " + bottom + " , view " + i + " top is " + child.getTop());
if (child.getTop() <= bottom) {
break;
} else {
start = i;
count++;
int position = firstPosition + i;
if (position >= headerViewsCount && position < footerViewsStart) {
mRecycler.addScrapView(child);
int columnIndex = (Integer) child.getTag();
if (columnIndex >= 0 && columnIndex < mColumnCount) {
mColumnViews[columnIndex].remove(child);
}
}
}
}
}
mMotionViewNewTop = mMotionViewOriginalTop + deltaY;
mBlockLayoutRequests = true;
if (count > 0) {
detachViewsFromParent(start, count);
// Log.d("TAG", "detach view from " + start + " , count is " + count);
}
tryOffsetChildrenTopAndBottom(incrementalDeltaY);
if (down) {
mFirstPosition += count;
}
invalidate();
final int absIncrementalDeltaY = Math.abs(incrementalDeltaY);
if (spaceAbove < absIncrementalDeltaY || spaceBelow < absIncrementalDeltaY) {
Log.d("TAG", "fill gap invoked");
fillGap(down, down ? lastBottom : firstTop);
}
if (!inTouchMode && mSelectedPosition != INVALID_POSITION) {
final int childIndex = mSelectedPosition - mFirstPosition;
if (childIndex >= 0 && childIndex < getChildCount()) {
positionSelector(getChildAt(childIndex));
}
}
mBlockLayoutRequests = false;
invokeOnItemScrollListener();
awakenScrollBars();
return false;
}
protected void tryOffsetChildrenTopAndBottom(int offset) {
final int count = getChildCount();
for (int i = 0; i < count; i++) {
final View v = getChildAt(i);
v.offsetTopAndBottom(offset);
}
}
/**
* Returns the number of header views in the list. Header views are special
* views at the top of the list that should not be recycled during a layout.
*
* @return The number of header views, 0 in the default implementation.
*/
int getHeaderViewsCount() {
return 0;
}
/**
* Returns the number of footer views in the list. Footer views are special
* views at the bottom of the list that should not be recycled during a
* layout.
*
* @return The number of footer views, 0 in the default implementation.
*/
int getFooterViewsCount() {
return 0;
}
/**
* Fills the gap left open by a touch-scroll. During a touch scroll,
* children that remain on screen are shifted and the other ones are
* discarded. The role of this method is to fill the gap thus created by
* performing a partial layout in the empty space.
*
* @param down
* true if the scroll is going down, false if it is going up
*/
abstract void fillGap(boolean down, int startOffset);
void hideSelector() {
if (mSelectedPosition != INVALID_POSITION) {
if (mLayoutMode != LAYOUT_SPECIFIC) {
mResurrectToPosition = mSelectedPosition;
}
if (mNextSelectedPosition >= 0 && mNextSelectedPosition != mSelectedPosition) {
mResurrectToPosition = mNextSelectedPosition;
}
setSelectedPositionInt(INVALID_POSITION);
setNextSelectedPositionInt(INVALID_POSITION);
mSelectedTop = 0;
mSelectorRect.setEmpty();
}
}
/**
* @return A position to select. First we try mSelectedPosition. If that has
* been clobbered by entering touch mode, we then try
* mResurrectToPosition. Values are pinned to the range of items
* available in the adapter
*/
int reconcileSelectedPosition() {
int position = mSelectedPosition;
if (position < 0) {
position = mResurrectToPosition;
}
position = Math.max(0, position);
position = Math.min(position, mItemCount - 1);
return position;
}
/**
* Find the row closest to y. This row will be used as the motion row when
* scrolling
*
* @param y
* Where the user touched
* @return The position of the first (or only) item in the row containing y
*/
abstract int findMotionRow(int y);
/**
* Find the row closest to y. This row will be used as the motion row when
* scrolling.
*
* @param y
* Where the user touched
* @return The position of the first (or only) item in the row closest to y
*/
int findClosestMotionRow(int y) {
final int childCount = getChildCount();
if (childCount == 0) {
return INVALID_POSITION;
}
final int motionRow = findMotionRow(y);
return motionRow != INVALID_POSITION ? motionRow : mFirstPosition + childCount - 1;
}
/**
* Causes all the views to be rebuilt and redrawn.
*/
public void invalidateViews() {
mDataChanged = true;
rememberSyncState();
requestLayout();
invalidate();
}
/**
* Makes the item at the supplied position selected.
*
* @param position
* the position of the new selection
*/
abstract void setSelectionInt(int position);
/**
* Attempt to bring the selection back if the user is switching from touch
* to trackball mode
*
* @return Whether selection was set to something.
*/
boolean resurrectSelection() {
final int childCount = getChildCount();
if (childCount <= 0) {
return false;
}
int selectedTop = 0;
int selectedPos;
int childrenTop = mListPadding.top;
int childrenBottom = getBottom() - getTop() - mListPadding.bottom;
final int firstPosition = mFirstPosition;
final int toPosition = mResurrectToPosition;
boolean down = true;
if (toPosition >= firstPosition && toPosition < firstPosition + childCount) {
selectedPos = toPosition;
final View selected = getChildAt(selectedPos - mFirstPosition);
selectedTop = selected.getTop();
int selectedBottom = selected.getBottom();
// We are scrolled, don't get in the fade
if (selectedTop < childrenTop) {
selectedTop = childrenTop + getVerticalFadingEdgeLength();
} else if (selectedBottom > childrenBottom) {
selectedTop = childrenBottom - selected.getMeasuredHeight()
- getVerticalFadingEdgeLength();
}
} else {
if (toPosition < firstPosition) {
// Default to selecting whatever is first
selectedPos = firstPosition;
for (int i = 0; i < childCount; i++) {
final View v = getChildAt(i);
final int top = v.getTop();
if (i == 0) {
// Remember the position of the first item
selectedTop = top;
// See if we are scrolled at all
if (firstPosition > 0 || top < childrenTop) {
// If we are scrolled, don't select anything that is
// in the fade region
childrenTop += getVerticalFadingEdgeLength();
}
}
if (top >= childrenTop) {
// Found a view whose top is fully visisble
selectedPos = firstPosition + i;
selectedTop = top;
break;
}
}
} else {
final int itemCount = mItemCount;
down = false;
selectedPos = firstPosition + childCount - 1;
for (int i = childCount - 1; i >= 0; i--) {
final View v = getChildAt(i);
final int top = v.getTop();
final int bottom = v.getBottom();
if (i == childCount - 1) {
selectedTop = top;
if (firstPosition + childCount < itemCount || bottom > childrenBottom) {
childrenBottom -= getVerticalFadingEdgeLength();
}
}
if (bottom <= childrenBottom) {
selectedPos = firstPosition + i;
selectedTop = top;
break;
}
}
}
}
mResurrectToPosition = INVALID_POSITION;
removeCallbacks(mFlingRunnable);
mTouchMode = TOUCH_MODE_REST;
clearScrollingCache();
mSpecificTop = selectedTop;
selectedPos = lookForSelectablePosition(selectedPos, down);
if (selectedPos >= firstPosition && selectedPos <= getLastVisiblePosition()) {
mLayoutMode = LAYOUT_SPECIFIC;
setSelectionInt(selectedPos);
invokeOnItemScrollListener();
} else {
selectedPos = INVALID_POSITION;
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
return selectedPos >= 0;
}
@Override
protected void handleDataChanged() {
int count = mItemCount;
if (count > 0) {
int newPos;
int selectablePos;
// Find the row we are supposed to sync to
if (mNeedSync) {
// Update this first, since setNextSelectedPositionInt inspects
// it
mNeedSync = false;
if (mTranscriptMode == TRANSCRIPT_MODE_ALWAYS_SCROLL
|| (mTranscriptMode == TRANSCRIPT_MODE_NORMAL && mFirstPosition
+ getChildCount() >= mOldItemCount)) {
mLayoutMode = LAYOUT_FORCE_BOTTOM;
return;
}
switch (mSyncMode) {
case SYNC_SELECTED_POSITION:
if (isInTouchMode()) {
// We saved our state when not in touch mode. (We know
// this because
// mSyncMode is SYNC_SELECTED_POSITION.) Now we are
// trying to
// restore in touch mode. Just leave mSyncPosition as it
// is (possibly
// adjusting if the available range changed) and return.
mLayoutMode = LAYOUT_SYNC;
mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1);
return;
} else {
// See if we can find a position in the new data with
// the same
// id as the old selection. This will change
// mSyncPosition.
newPos = findSyncPosition();
if (newPos >= 0) {
// Found it. Now verify that new selection is still
// selectable
selectablePos = lookForSelectablePosition(newPos, true);
if (selectablePos == newPos) {
// Same row id is selected
mSyncPosition = newPos;
if (mSyncHeight == getHeight()) {
// If we are at the same height as when we
// saved state, try
// to restore the scroll position too.
mLayoutMode = LAYOUT_SYNC;
} else {
// We are not the same height as when the
// selection was saved, so
// don't try to restore the exact position
mLayoutMode = LAYOUT_SET_SELECTION;
}
// Restore selection
setNextSelectedPositionInt(newPos);
return;
}
}
}
break;
case SYNC_FIRST_POSITION:
// Leave mSyncPosition as it is -- just pin to available
// range
mLayoutMode = LAYOUT_SYNC;
mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1);
return;
}
}
if (!isInTouchMode()) {
// We couldn't find matching data -- try to use the same
// position
newPos = getSelectedItemPosition();
// Pin position to the available range
if (newPos >= count) {
newPos = count - 1;
}
if (newPos < 0) {
newPos = 0;
}
// Make sure we select something selectable -- first look down
selectablePos = lookForSelectablePosition(newPos, true);
if (selectablePos >= 0) {
setNextSelectedPositionInt(selectablePos);
return;
} else {
// Looking down didn't work -- try looking up
selectablePos = lookForSelectablePosition(newPos, false);
if (selectablePos >= 0) {
setNextSelectedPositionInt(selectablePos);
return;
}
}
} else {
// We already know where we want to resurrect the selection
if (mResurrectToPosition >= 0) {
return;
}
}
}
// Nothing is selected. Give up and reset everything.
mLayoutMode = mStackFromBottom ? LAYOUT_FORCE_BOTTOM : LAYOUT_FORCE_TOP;
mSelectedPosition = INVALID_POSITION;
mSelectedRowId = INVALID_ROW_ID;
mNextSelectedPosition = INVALID_POSITION;
mNextSelectedRowId = INVALID_ROW_ID;
mNeedSync = false;
checkSelectionChanged();
}
@Override
protected void onDisplayHint(int hint) {
super.onDisplayHint(hint);
switch (hint) {
case INVISIBLE:
if (mPopup != null && mPopup.isShowing()) {
dismissPopup();
}
break;
case VISIBLE:
if (mFiltered && mPopup != null && !mPopup.isShowing()) {
showPopup();
}
break;
}
mPopupHidden = hint == INVISIBLE;
}
/**
* Removes the filter window
*/
private void dismissPopup() {
if (mPopup != null) {
mPopup.dismiss();
}
}
/**
* Shows the filter window
*/
private void showPopup() {
// Make sure we have a window before showing the popup
if (getWindowVisibility() == View.VISIBLE) {
positionPopup();
// Make sure we get focus if we are showing the popup
checkFocus();
}
}
private void positionPopup() {
int screenHeight = getResources().getDisplayMetrics().heightPixels;
final int[] xy = new int[2];
getLocationOnScreen(xy);
// TODO: The 20 below should come from the theme
// TODO: And the gravity should be defined in the theme as well
final int bottomGap = screenHeight - xy[1] - getHeight() + (int) (mDensityScale * 20);
if (!mPopup.isShowing()) {
mPopup.showAtLocation(this, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, xy[0],
bottomGap);
} else {
mPopup.update(xy[0], bottomGap, -1, -1);
}
}
/**
* What is the distance between the source and destination rectangles given
* the direction of focus navigation between them? The direction basically
* helps figure out more quickly what is self evident by the relationship
* between the rects...
*
* @param source
* the source rectangle
* @param dest
* the destination rectangle
* @param direction
* the direction
* @return the distance between the rectangles
*/
static int getDistance(Rect source, Rect dest, int direction) {
int sX, sY; // source x, y
int dX, dY; // dest x, y
switch (direction) {
case View.FOCUS_RIGHT:
sX = source.right;
sY = source.top + source.height() / 2;
dX = dest.left;
dY = dest.top + dest.height() / 2;
break;
case View.FOCUS_DOWN:
sX = source.left + source.width() / 2;
sY = source.bottom;
dX = dest.left + dest.width() / 2;
dY = dest.top;
break;
case View.FOCUS_LEFT:
sX = source.left;
sY = source.top + source.height() / 2;
dX = dest.right;
dY = dest.top + dest.height() / 2;
break;
case View.FOCUS_UP:
sX = source.left + source.width() / 2;
sY = source.top;
dX = dest.left + dest.width() / 2;
dY = dest.bottom;
break;
default:
throw new IllegalArgumentException("direction must be one of "
+ "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}.");
}
int deltaX = dX - sX;
int deltaY = dY - sY;
return deltaY * deltaY + deltaX * deltaX;
}
@Override
protected boolean isInFilterMode() {
return mFiltered;
}
/**
* Returns if the ListView currently has a text filter.
*/
public boolean hasTextFilter() {
return mFiltered;
}
public void onGlobalLayout() {
if (isShown()) {
// Show the popup if we are filtered
if (mFiltered && mPopup != null && !mPopup.isShowing() && !mPopupHidden) {
showPopup();
}
} else {
// Hide the popup when we are no longer visible
if (mPopup != null && mPopup.isShowing()) {
dismissPopup();
}
}
}
public void onFilterComplete(int count) {
if (mSelectedPosition < 0 && count > 0) {
mResurrectToPosition = INVALID_POSITION;
resurrectSelection();
}
}
@Override
protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) {
return new LayoutParams(p);
}
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new AbsListView.LayoutParams(getContext(), attrs);
}
@Override
protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
return p instanceof AbsListView.LayoutParams;
}
/**
* Puts the list or grid into transcript mode. In this mode the list or grid
* will always scroll to the bottom to show new items.
*
* @param mode
* the transcript mode to set
*
* @see #TRANSCRIPT_MODE_DISABLED
* @see #TRANSCRIPT_MODE_NORMAL
* @see #TRANSCRIPT_MODE_ALWAYS_SCROLL
*/
public void setTranscriptMode(int mode) {
mTranscriptMode = mode;
}
/**
* Returns the current transcript mode.
*
* @return {@link #TRANSCRIPT_MODE_DISABLED},
* {@link #TRANSCRIPT_MODE_NORMAL} or
* {@link #TRANSCRIPT_MODE_ALWAYS_SCROLL}
*/
public int getTranscriptMode() {
return mTranscriptMode;
}
@Override
public int getSolidColor() {
return mCacheColorHint;
}
/**
* When set to a non-zero value, the cache color hint indicates that this
* list is always drawn on top of a solid, single-color, opaque background
*
* @param color
* The background color
*/
public void setCacheColorHint(int color) {
if (color != mCacheColorHint) {
mCacheColorHint = color;
int count = getChildCount();
for (int i = 0; i < count; i++) {
getChildAt(i).setDrawingCacheBackgroundColor(color);
}
mRecycler.setCacheColorHint(color);
}
}
/**
* When set to a non-zero value, the cache color hint indicates that this
* list is always drawn on top of a solid, single-color, opaque background
*
* @return The cache color hint
*/
public int getCacheColorHint() {
return mCacheColorHint;
}
/**
* Move all views (excluding headers and footers) held by this AbsListView
* into the supplied List. This includes views displayed on the screen as
* well as views stored in AbsListView's internal view recycler.
*
* @param views
* A list into which to put the reclaimed views
*/
public void reclaimViews(List<View> views) {
int childCount = getChildCount();
RecyclerListener listener = mRecycler.mRecyclerListener;
// Reclaim views on screen
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams();
// Don't reclaim header or footer views, or views that should be
// ignored
if (lp != null && mRecycler.shouldRecycleViewType(lp.viewType)) {
views.add(child);
if (listener != null) {
// Pretend they went through the scrap heap
listener.onMovedToScrapHeap(child);
}
}
}
mRecycler.reclaimScrapViews(views);
removeAllViewsInLayout();
}
// /**
// * @hide
// */
// @Override
// protected boolean onConsistencyCheck(int consistency) {
// boolean result = super.onConsistencyCheck(consistency);
//
// final boolean checkLayout = (consistency & ViewDebug.CONSISTENCY_LAYOUT) != 0;
//
// if (checkLayout) {
// // The active recycler must be empty
// final View[] activeViews = mRecycler.mActiveViews;
// int count = activeViews.length;
// for (int i = 0; i < count; i++) {
// if (activeViews[i] != null) {
// result = false;
// Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this
// + " has a view in its active recycler: " + activeViews[i]);
// }
// }
//
// // All views in the recycler must NOT be on screen and must NOT have
// // a parent
// final ArrayList<View> scrap = mRecycler.mCurrentScrap;
// if (!checkScrap(scrap))
// result = false;
// final ArrayList<View>[] scraps = mRecycler.mScrapViews;
// count = scraps.length;
// for (int i = 0; i < count; i++) {
// if (!checkScrap(scraps[i]))
// result = false;
// }
// }
//
// return result;
// }
//
// private boolean checkScrap(ArrayList<View> scrap) {
// if (scrap == null)
// return true;
// boolean result = true;
//
// final int count = scrap.size();
// for (int i = 0; i < count; i++) {
// final View view = scrap.get(i);
// if (view.getParent() != null) {
// result = false;
// Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this
// + " has a view in its scrap heap still attached to a parent: " + view);
// }
// if (indexOfChild(view) >= 0) {
// result = false;
// Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this
// + " has a view in its scrap heap that is also a direct child: " + view);
// }
// }
//
// return result;
// }
/**
* Sets the recycler listener to be notified whenever a View is set aside in
* the recycler for later reuse. This listener can be used to free resources
* associated to the View.
*
* @param listener
* The recycler listener to be notified of views set aside in the
* recycler.
*
* @see android.widget.AbsListView.RecycleBin
* @see android.widget.AbsListView.RecyclerListener
*/
public void setRecyclerListener(RecyclerListener listener) {
mRecycler.mRecyclerListener = listener;
}
/**
* AbsListView extends LayoutParams to provide a place to hold the view
* type.
*/
public static class LayoutParams extends ViewGroup.LayoutParams {
/**
* View type for this view, as returned by
* {@link android.widget.Adapter#getItemViewType(int) }
*/
@ViewDebug.ExportedProperty(mapping = {
@ViewDebug.IntToString(from = ITEM_VIEW_TYPE_IGNORE, to = "ITEM_VIEW_TYPE_IGNORE"),
@ViewDebug.IntToString(from = ITEM_VIEW_TYPE_HEADER_OR_FOOTER, to = "ITEM_VIEW_TYPE_HEADER_OR_FOOTER") })
int viewType;
/**
* When this boolean is set, the view has been added to the AbsListView
* at least once. It is used to know whether headers/footers have
* already been added to the list view and whether they should be
* treated as recycled views or not.
*/
@ViewDebug.ExportedProperty
boolean recycledHeaderFooter;
/**
* When an AbsListView is measured with an AT_MOST measure spec, it
* needs to obtain children views to measure itself. When doing so, the
* children are not attached to the window, but put in the recycler
* which assumes they've been attached before. Setting this flag will
* force the reused view to be attached to the window rather than just
* attached to the parent.
*/
@ViewDebug.ExportedProperty
boolean forceAdd;
public LayoutParams(Context c, AttributeSet attrs) {
super(c, attrs);
}
public LayoutParams(int w, int h) {
super(w, h);
}
public LayoutParams(int w, int h, int viewType) {
super(w, h);
this.viewType = viewType;
}
public LayoutParams(ViewGroup.LayoutParams source) {
super(source);
}
}
/**
* A RecyclerListener is used to receive a notification whenever a View is
* placed inside the RecycleBin's scrap heap. This listener is used to free
* resources associated to Views placed in the RecycleBin.
*
* @see android.widget.AbsListView.RecycleBin
* @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener)
*/
public static interface RecyclerListener {
/**
* Indicates that the specified View was moved into the recycler's scrap
* heap. The view is not displayed on screen any more and any expensive
* resource associated with the view should be discarded.
*
* @param view
*/
void onMovedToScrapHeap(View view);
}
/**
* The RecycleBin facilitates reuse of views across layouts. The RecycleBin
* has two levels of storage: ActiveViews and ScrapViews. ActiveViews are
* those views which were onscreen at the start of a layout. By
* construction, they are displaying current information. At the end of
* layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews
* are old views that could potentially be used by the adapter to avoid
* allocating views unnecessarily.
*
* @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener)
* @see android.widget.AbsListView.RecyclerListener
*/
class RecycleBin {
private RecyclerListener mRecyclerListener;
/**
* The position of the first view stored in mActiveViews.
*/
private int mFirstActivePosition;
/**
* Views that were on screen at the start of layout. This array is
* populated at the start of layout, and at the end of layout all view
* in mActiveViews are moved to mScrapViews. Views in mActiveViews
* represent a contiguous range of Views, with position of the first
* view store in mFirstActivePosition.
*/
private View[] mActiveViews = new View[0];
/**
* Unsorted views that can be used by the adapter as a convert view.
*/
private ArrayList<View>[] mScrapViews;
private int mViewTypeCount;
private ArrayList<View> mCurrentScrap;
public void setViewTypeCount(int viewTypeCount) {
if (viewTypeCount < 1) {
throw new IllegalArgumentException("Can't have a viewTypeCount < 1");
}
// noinspection unchecked
ArrayList<View>[] scrapViews = new ArrayList[viewTypeCount];
for (int i = 0; i < viewTypeCount; i++) {
scrapViews[i] = new ArrayList<View>();
}
mViewTypeCount = viewTypeCount;
mCurrentScrap = scrapViews[0];
mScrapViews = scrapViews;
}
public void markChildrenDirty() {
if (mViewTypeCount == 1) {
final ArrayList<View> scrap = mCurrentScrap;
final int scrapCount = scrap.size();
for (int i = 0; i < scrapCount; i++) {
scrap.get(i).forceLayout();
}
} else {
final int typeCount = mViewTypeCount;
for (int i = 0; i < typeCount; i++) {
final ArrayList<View> scrap = mScrapViews[i];
final int scrapCount = scrap.size();
for (int j = 0; j < scrapCount; j++) {
scrap.get(j).forceLayout();
}
}
}
}
public boolean shouldRecycleViewType(int viewType) {
return viewType >= 0;
}
/**
* Clears the scrap heap.
*/
void clear() {
if (mViewTypeCount == 1) {
final ArrayList<View> scrap = mCurrentScrap;
final int scrapCount = scrap.size();
for (int i = 0; i < scrapCount; i++) {
removeDetachedView(scrap.remove(scrapCount - 1 - i), false);
}
} else {
final int typeCount = mViewTypeCount;
for (int i = 0; i < typeCount; i++) {
final ArrayList<View> scrap = mScrapViews[i];
final int scrapCount = scrap.size();
for (int j = 0; j < scrapCount; j++) {
removeDetachedView(scrap.remove(scrapCount - 1 - j), false);
}
}
}
}
/**
* Fill ActiveViews with all of the children of the AbsListView.
*
* @param childCount
* The minimum number of views mActiveViews should hold
* @param firstActivePosition
* The position of the first view that will be stored in
* mActiveViews
*/
void fillActiveViews(int childCount, int firstActivePosition) {
if (mActiveViews.length < childCount) {
mActiveViews = new View[childCount];
}
mFirstActivePosition = firstActivePosition;
final View[] activeViews = mActiveViews;
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams();
// Don't put header or footer views into the scrap heap
if (lp != null && lp.viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
// Note: We do place AdapterView.ITEM_VIEW_TYPE_IGNORE in
// active views.
// However, we will NOT place them into scrap views.
activeViews[i] = child;
}
}
}
/**
* Get the view corresponding to the specified position. The view will
* be removed from mActiveViews if it is found.
*
* @param position
* The position to look up in mActiveViews
* @return The view if it is found, null otherwise
*/
View getActiveView(int position) {
int index = position - mFirstActivePosition;
final View[] activeViews = mActiveViews;
if (index >= 0 && index < activeViews.length) {
final View match = activeViews[index];
activeViews[index] = null;
return match;
}
return null;
}
/**
* @return A view from the ScrapViews collection. These are unordered.
*/
View getScrapView(int position) {
ArrayList<View> scrapViews;
if (mViewTypeCount == 1) {
scrapViews = mCurrentScrap;
int size = scrapViews.size();
// Log.d("TAG", "get scrap view size is " + size);
if (size > 0) {
return scrapViews.remove(size - 1);
} else {
return null;
}
} else {
int whichScrap = mAdapter.getItemViewType(position);
if (whichScrap >= 0 && whichScrap < mScrapViews.length) {
scrapViews = mScrapViews[whichScrap];
int size = scrapViews.size();
if (size > 0) {
return scrapViews.remove(size - 1);
}
}
}
return null;
}
/**
* Put a view into the ScapViews list. These views are unordered.
*
* @param scrap
* The view to add
*/
void addScrapView(View scrap) {
AbsListView.LayoutParams lp = (AbsListView.LayoutParams) scrap.getLayoutParams();
if (lp == null) {
return;
}
// Don't put header or footer views or views that should be ignored
// into the scrap heap
int viewType = lp.viewType;
if (!shouldRecycleViewType(viewType)) {
if (viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
removeDetachedView(scrap, false);
}
return;
}
if (mViewTypeCount == 1) {
dispatchFinishTemporaryDetach(scrap);
mCurrentScrap.add(scrap);
// Log.d("TAG", "add scrap view size is " + mCurrentScrap.size());
} else {
dispatchFinishTemporaryDetach(scrap);
mScrapViews[viewType].add(scrap);
}
if (mRecyclerListener != null) {
mRecyclerListener.onMovedToScrapHeap(scrap);
}
}
/**
* Move all views remaining in mActiveViews to mScrapViews.
*/
void scrapActiveViews() {
final View[] activeViews = mActiveViews;
final boolean hasListener = mRecyclerListener != null;
final boolean multipleScraps = mViewTypeCount > 1;
ArrayList<View> scrapViews = mCurrentScrap;
final int count = activeViews.length;
for (int i = count - 1; i >= 0; i--) {
final View victim = activeViews[i];
if (victim != null) {
int whichScrap = ((AbsListView.LayoutParams) victim.getLayoutParams()).viewType;
activeViews[i] = null;
if (!shouldRecycleViewType(whichScrap)) {
// Do not move views that should be ignored
if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
removeDetachedView(victim, false);
}
continue;
}
if (multipleScraps) {
scrapViews = mScrapViews[whichScrap];
}
// victim.dispatchStartTemporaryDetach();
dispatchFinishTemporaryDetach(victim);
scrapViews.add(victim);
if (hasListener) {
mRecyclerListener.onMovedToScrapHeap(victim);
}
if (ViewDebug.TRACE_RECYCLER) {
ViewDebug.trace(victim,
ViewDebug.RecyclerTraceType.MOVE_FROM_ACTIVE_TO_SCRAP_HEAP,
mFirstActivePosition + i, -1);
}
}
}
pruneScrapViews();
}
/**
* Makes sure that the size of mScrapViews does not exceed the size of
* mActiveViews. (This can happen if an adapter does not recycle its
* views).
*/
private void pruneScrapViews() {
final int maxViews = mActiveViews.length;
final int viewTypeCount = mViewTypeCount;
final ArrayList<View>[] scrapViews = mScrapViews;
for (int i = 0; i < viewTypeCount; ++i) {
final ArrayList<View> scrapPile = scrapViews[i];
int size = scrapPile.size();
final int extras = size - maxViews;
size--;
for (int j = 0; j < extras; j++) {
removeDetachedView(scrapPile.remove(size--), false);
}
}
}
/**
* Puts all views in the scrap heap into the supplied list.
*/
void reclaimScrapViews(List<View> views) {
if (mViewTypeCount == 1) {
views.addAll(mCurrentScrap);
} else {
final int viewTypeCount = mViewTypeCount;
final ArrayList<View>[] scrapViews = mScrapViews;
for (int i = 0; i < viewTypeCount; ++i) {
final ArrayList<View> scrapPile = scrapViews[i];
views.addAll(scrapPile);
}
}
}
/**
* Updates the cache color hint of all known views.
*
* @param color
* The new cache color hint.
*/
void setCacheColorHint(int color) {
if (mViewTypeCount == 1) {
final ArrayList<View> scrap = mCurrentScrap;
final int scrapCount = scrap.size();
for (int i = 0; i < scrapCount; i++) {
scrap.get(i).setDrawingCacheBackgroundColor(color);
}
} else {
final int typeCount = mViewTypeCount;
for (int i = 0; i < typeCount; i++) {
final ArrayList<View> scrap = mScrapViews[i];
final int scrapCount = scrap.size();
for (int j = 0; j < scrapCount; j++) {
scrap.get(i).setDrawingCacheBackgroundColor(color);
}
}
}
// Just in case this is called during a layout pass
final View[] activeViews = mActiveViews;
final int count = activeViews.length;
for (int i = 0; i < count; ++i) {
final View victim = activeViews[i];
if (victim != null) {
victim.setDrawingCacheBackgroundColor(color);
}
}
}
}
}