package net.osmand.plus.views.controls;
/*
* Copyright (C) 2013 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 android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ObjectAnimator;
import android.animation.TypeEvaluator;
import android.animation.ValueAnimator;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.support.annotation.NonNull;
import android.support.v4.view.ViewCompat;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.widget.AbsListView;
import android.widget.HeaderViewListAdapter;
import android.widget.ListAdapter;
import com.github.ksoichiro.android.observablescrollview.ObservableListView;
import java.util.List;
public class DynamicListView extends ObservableListView {
protected final int SMOOTH_SCROLL_AMOUNT_AT_EDGE = 15;
protected final int MOVE_DURATION = 150;
protected List<Object> mItemsList;
protected List<Object> mActiveItemsList;
private DynamicListViewCallbacks dCallbacks;
private int mLastEventY = -1;
protected int mDownY = -1;
protected int mDownX = -1;
private int mTotalOffset = 0;
private boolean mCellIsMobile = false;
private boolean mIsMobileScrolling = false;
private int mSmoothScrollAmountAtEdge = 0;
private boolean itemsSwapped = false;
protected final int INVALID_ID = -1;
private long mAboveItemId = INVALID_ID;
private long mMobileItemId = INVALID_ID;
private long mBelowItemId = INVALID_ID;
private BitmapDrawable mHoverCell;
private Rect mHoverCellCurrentBounds;
private Rect mHoverCellOriginalBounds;
protected final int INVALID_POINTER_ID = -1;
private int mActivePointerId = INVALID_POINTER_ID;
private boolean mIsWaitingForScrollFinish = false;
private int mScrollState = OnScrollListener.SCROLL_STATE_IDLE;
private GestureDetector singleTapDetector;
private DragIcon tag;
public interface DragIcon {
void onClick();
}
public DynamicListView(Context context) {
super(context);
init(context);
}
public DynamicListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
public DynamicListView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public void init(Context context) {
setOnScrollListener(mScrollListener);
DisplayMetrics metrics = context.getResources().getDisplayMetrics();
mSmoothScrollAmountAtEdge = (int) (SMOOTH_SCROLL_AMOUNT_AT_EDGE / metrics.density);
singleTapDetector = new GestureDetector(context, new SingleTapConfirm());
}
public void setDynamicListViewCallbacks(DynamicListViewCallbacks callbacks) {
dCallbacks = callbacks;
}
/**
* Creates the hover cell with the appropriate bitmap and of appropriate
* size. The hover cell's BitmapDrawable is drawn on top of the bitmap every
* single time an invalidate call is made.
*/
private BitmapDrawable getAndAddHoverView(View v) {
int w = v.getWidth();
int h = v.getHeight();
int top = v.getTop();
int left = v.getLeft();
Bitmap b = getBitmapFromView(v);
BitmapDrawable drawable = new BitmapDrawable(getResources(), b);
mHoverCellOriginalBounds = new Rect(left, top, left + w, top + h);
mHoverCellCurrentBounds = new Rect(mHoverCellOriginalBounds);
drawable.setBounds(mHoverCellCurrentBounds);
return drawable;
}
/**
* Returns a bitmap showing a screenshot of the view passed in.
*/
private Bitmap getBitmapFromView(View v) {
Bitmap bitmap = Bitmap.createBitmap(v.getWidth(), v.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
v.draw(canvas);
Bitmap bitmapOut = Bitmap.createBitmap(v.getWidth(), v.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvasOut = new Canvas(bitmapOut);
canvasOut.drawColor(Color.TRANSPARENT);
Paint p = new Paint();
p.setAlpha(200);
canvasOut.drawBitmap(bitmap, 0, 0, p);
return bitmapOut;
}
public StableArrayAdapter getStableAdapter() {
ListAdapter listAdapter = getAdapter();
if (listAdapter instanceof HeaderViewListAdapter) {
listAdapter = ((HeaderViewListAdapter) listAdapter).getWrappedAdapter();
}
if (listAdapter instanceof StableArrayAdapter) {
return (StableArrayAdapter) listAdapter;
}
return null;
}
/**
* Stores a reference to the views above and below the item currently
* corresponding to the hover cell. It is important to note that if this
* item is either at the top or bottom of the list, mAboveItemId or mBelowItemId
* may be invalid.
*/
private void updateNeighborViewsForID(long itemID) {
ListAdapter adapter = getAdapter();
int position = getPositionForID(itemID);
int pos = position;
mAboveItemId = INVALID_ID;
while (mAboveItemId == INVALID_ID && pos > 0) {
pos--;
mAboveItemId = adapter.getItemId(pos);
if (mAboveItemId != INVALID_ID) {
Object obj = adapter.getItem(pos);
if (mActiveItemsList == null || !mActiveItemsList.contains(obj)) {
mAboveItemId = INVALID_ID;
}
}
}
pos = position;
mBelowItemId = INVALID_ID;
while (mBelowItemId == INVALID_ID && pos < mItemsList.size()) {
pos++;
mBelowItemId = adapter.getItemId(pos);
if (mBelowItemId != INVALID_ID) {
Object obj = adapter.getItem(pos);
if (mActiveItemsList == null || !mActiveItemsList.contains(obj)) {
mBelowItemId = INVALID_ID;
}
}
}
}
/**
* Retrieves the view in the list corresponding to itemID
*/
public View getViewForID(long itemID) {
if (itemID != INVALID_ID) {
int firstVisiblePosition = getFirstVisiblePosition();
ListAdapter adapter = getAdapter();
for (int i = 0; i < getChildCount(); i++) {
View v = getChildAt(i);
int position = firstVisiblePosition + i;
long id = adapter.getItemId(position);
if (id == itemID) {
return v;
}
}
}
return null;
}
public void setAllVisible() {
for (int i = 0; i < getChildCount(); i++) {
View v = getChildAt(i);
if (v != null && v.getVisibility() != VISIBLE) {
v.setVisibility(VISIBLE);
}
}
}
/**
* Retrieves the position in the list corresponding to itemID
*/
public int getPositionForID(long itemID) {
View v = getViewForID(itemID);
if (v == null) {
return -1;
} else {
return getPositionForView(v);
}
}
/**
* dispatchDraw gets invoked when all the child views are about to be drawn.
* By overriding this method, the hover cell (BitmapDrawable) can be drawn
* over the listview's items whenever the listview is redrawn.
*/
@Override
protected void dispatchDraw(@NonNull Canvas canvas) {
super.dispatchDraw(canvas);
if (mHoverCell != null) {
mHoverCell.draw(canvas);
}
// Draw dividers
StableArrayAdapter stableAdapter = getStableAdapter();
if (getDivider() == null && stableAdapter != null && stableAdapter.hasDividers()) {
List<Drawable> dividers = stableAdapter.getDividers();
final int count = getChildCount();
final int first = getFirstVisiblePosition();
final int headerCount = getHeaderViewsCount();
final int itemCount = getCount();
final int footerLimit = (itemCount - getFooterViewsCount());
final Rect bounds = new Rect();
bounds.left = getPaddingLeft();
bounds.right = getRight() - getLeft() - getPaddingRight();
final int listBottom = getBottom() - getTop() + getScrollY();
for (int i = 0; i < count; i++) {
final int itemIndex = (first + i);
final boolean isHeader = (itemIndex < headerCount);
final boolean isFooter = (itemIndex >= footerLimit);
if (!isHeader && !isFooter && itemIndex < dividers.size()) {
Drawable divider = dividers.get(itemIndex - headerCount);
if (divider != null) {
final View child = getChildAt(i);
int bottom = child.getBottom();
final boolean isLastItem = (i == (count - 1));
if (bottom < listBottom && !isLastItem) {
final int nextIndex = (itemIndex + 1);
if (nextIndex >= headerCount && nextIndex < footerLimit) {
bounds.top = bottom;
bounds.bottom = bottom + divider.getIntrinsicHeight();
drawDivider(canvas, divider, bounds);
}
}
}
}
}
}
}
void drawDivider(Canvas canvas, Drawable divider, Rect bounds) {
divider.setBounds(bounds);
divider.draw(canvas);
}
@Override
public boolean onTouchEvent(@NonNull MotionEvent event) {
if (singleTapDetector.onTouchEvent(event)) {
if (tag != null) {
tag.onClick();
}
touchEventsCancelled();
return super.onTouchEvent(event);
}
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
if (!mCellIsMobile && mHoverCell == null) {
// Find the view that the user pressed their finger down on.
View v = findViewAtPositionWithDragIconTag(getRootView(), (int) event.getRawX(), (int) event.getRawY());
// If the view contains a tag set to "DragIcon" class, it means that the user wants to
// reorder the list item.
if ((v != null) && (v.getTag() != null) && (v.getTag() instanceof DragIcon)) {
mDownX = (int) event.getX();
mDownY = (int) event.getY();
mActivePointerId = event.getPointerId(0);
mTotalOffset = 0;
tag = (DragIcon) v.getTag();
int position = pointToPosition(mDownX, mDownY);
if (position != INVALID_POSITION) {
Object item = getAdapter().getItem(position);
if (mActiveItemsList == null || mActiveItemsList.contains(item)) {
int itemNum = position - getFirstVisiblePosition();
itemsSwapped = false;
View selectedView = getChildAt(itemNum);
mMobileItemId = getAdapter().getItemId(position);
mHoverCell = getAndAddHoverView(selectedView);
selectedView.setVisibility(INVISIBLE);
mCellIsMobile = true;
updateNeighborViewsForID(mMobileItemId);
if (dCallbacks != null) {
dCallbacks.onItemSwapping(position);
}
}
}
}
}
break;
case MotionEvent.ACTION_MOVE:
if (mActivePointerId == INVALID_POINTER_ID) {
break;
}
int pointerIndex = event.findPointerIndex(mActivePointerId);
mLastEventY = (int) event.getY(pointerIndex);
int deltaY = mLastEventY - mDownY;
if (mCellIsMobile && mHoverCell != null) {
mHoverCellCurrentBounds.offsetTo(mHoverCellOriginalBounds.left,
mHoverCellOriginalBounds.top + deltaY + mTotalOffset);
mHoverCell.setBounds(mHoverCellCurrentBounds);
invalidate();
handleCellSwitch();
mIsMobileScrolling = false;
handleMobileCellScroll();
return false;
}
break;
case MotionEvent.ACTION_UP:
touchEventsEnded();
break;
case MotionEvent.ACTION_CANCEL:
touchEventsCancelled();
break;
case MotionEvent.ACTION_POINTER_UP:
/* If a multitouch event took place and the original touch dictating
* the movement of the hover cell has ended, then the dragging event
* ends and the hover cell is animated to its corresponding position
* in the listview. */
pointerIndex = (event.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >>
MotionEvent.ACTION_POINTER_INDEX_SHIFT;
final int pointerId = event.getPointerId(pointerIndex);
if (pointerId == mActivePointerId) {
touchEventsEnded();
}
break;
default:
break;
}
return super.onTouchEvent(event);
}
/**
* This method determines whether the hover cell has been shifted far enough
* to invoke a cell swap. If so, then the respective cell swap candidate is
* determined and the data set is changed. Upon posting a notification of the
* data set change, a layout is invoked to place the cells in the right place.
* Using a ViewTreeObserver and a corresponding OnPreDrawListener, we can
* offset the cell being swapped to where it previously was and then animate it to
* its new position.
*/
private void handleCellSwitch() {
final int deltaY = mLastEventY - mDownY;
final int deltaYTotal = mHoverCellOriginalBounds.top + mTotalOffset + deltaY;
View belowView = getViewForID(mBelowItemId);
View mobileView = getViewForID(mMobileItemId);
View aboveView = getViewForID(mAboveItemId);
boolean isBelow = (belowView != null) && (deltaYTotal > belowView.getTop());
boolean isAbove = (aboveView != null) && (deltaYTotal < aboveView.getTop());
if (isBelow || isAbove) {
final long switchItemID = isBelow ? mBelowItemId : mAboveItemId;
View switchView = isBelow ? belowView : aboveView;
final int originalItem = getPositionForView(mobileView) - getHeaderViewsCount();
final int switchItem = getPositionForView(switchView) - getHeaderViewsCount();
swapElements(originalItem, switchItem);
getStableAdapter().notifyDataSetChanged();
mDownY = mLastEventY;
final int switchViewStartTop = switchView.getTop();
if (android.os.Build.VERSION.SDK_INT <= android.os.Build.VERSION_CODES.KITKAT) {
mobileView.setVisibility(View.VISIBLE);
switchView.setVisibility(View.INVISIBLE);
}
updateNeighborViewsForID(mMobileItemId);
final ViewTreeObserver observer = getViewTreeObserver();
observer.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
observer.removeOnPreDrawListener(this);
View switchView = getViewForID(switchItemID);
mTotalOffset += deltaY;
int switchViewNewTop = switchView.getTop();
int delta = switchViewStartTop - switchViewNewTop;
ViewCompat.setTranslationY(switchView, delta);
if (android.os.Build.VERSION.SDK_INT < 12) {
ViewCompat.animate(switchView)
.translationY(0)
.setDuration(MOVE_DURATION);
} else {
ObjectAnimator animator = ObjectAnimator.ofFloat(switchView,
View.TRANSLATION_Y, 0);
animator.setDuration(MOVE_DURATION);
animator.start();
}
return true;
}
});
}
}
private void swapElements(int indexOne, int indexTwo) {
Object obj1 = mItemsList.get(indexOne);
Object obj2 = mItemsList.get(indexTwo);
mItemsList.set(indexOne, obj2);
mItemsList.set(indexTwo, obj1);
int index1 = mActiveItemsList.indexOf(obj1);
int index2 = mActiveItemsList.indexOf(obj2);
if (index1 != -1 && index2 != -1) {
mActiveItemsList.set(index1, obj2);
mActiveItemsList.set(index2, obj1);
itemsSwapped = true;
}
}
/**
* Resets all the appropriate fields to a default state while also animating
* the hover cell back to its correct location.
*/
private void touchEventsEnded() {
final View mobileView = getViewForID(mMobileItemId);
if (mCellIsMobile || mIsWaitingForScrollFinish) {
mCellIsMobile = false;
mIsWaitingForScrollFinish = false;
mIsMobileScrolling = false;
mActivePointerId = INVALID_POINTER_ID;
// If the autoscroller has not completed scrolling, we need to wait for it to
// finish in order to determine the final location of where the hover cell
// should be animated to.
if (mScrollState != OnScrollListener.SCROLL_STATE_IDLE) {
mIsWaitingForScrollFinish = true;
return;
}
mHoverCellCurrentBounds.offsetTo(mHoverCellOriginalBounds.left, mobileView.getTop());
if (android.os.Build.VERSION.SDK_INT < 12) {
finishTouch();
} else {
/**
* This TypeEvaluator is used to animate the BitmapDrawable back to its
* final location when the user lifts his finger by modifying the
* BitmapDrawable's bounds.
*/
TypeEvaluator<Rect> sBoundEvaluator = new TypeEvaluator<Rect>() {
public Rect evaluate(float fraction, Rect startValue, Rect endValue) {
return new Rect(interpolate(startValue.left, endValue.left, fraction),
interpolate(startValue.top, endValue.top, fraction),
interpolate(startValue.right, endValue.right, fraction),
interpolate(startValue.bottom, endValue.bottom, fraction));
}
public int interpolate(int start, int end, float fraction) {
return (int) (start + fraction * (end - start));
}
};
ObjectAnimator hoverViewAnimator = ObjectAnimator.ofObject(mHoverCell, "bounds",
sBoundEvaluator, mHoverCellCurrentBounds);
hoverViewAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator valueAnimator) {
invalidate();
}
});
hoverViewAnimator.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationStart(Animator animation) {
setEnabled(false);
}
@Override
public void onAnimationEnd(Animator animation) {
finishTouch();
}
});
hoverViewAnimator.start();
}
} else {
touchEventsCancelled();
}
}
/**
* Resets all the appropriate fields to a default state.
*/
private void touchEventsCancelled() {
if (mCellIsMobile) {
finishTouch();
}
mCellIsMobile = false;
mIsMobileScrolling = false;
mActivePointerId = INVALID_POINTER_ID;
}
private void finishTouch() {
mAboveItemId = INVALID_ID;
mMobileItemId = INVALID_ID;
mBelowItemId = INVALID_ID;
setAllVisible();
mHoverCell = null;
tag = null;
setEnabled(true);
invalidate();
processSwapped();
}
private void processSwapped() {
if (itemsSwapped) {
itemsSwapped = false;
if (dCallbacks != null) {
dCallbacks.onItemsSwapped(mActiveItemsList);
}
}
}
/**
* Determines whether this listview is in a scrolling state invoked
* by the fact that the hover cell is out of the bounds of the listview;
*/
private void handleMobileCellScroll() {
mIsMobileScrolling = handleMobileCellScroll(mHoverCellCurrentBounds);
}
/**
* This method is in charge of determining if the hover cell is above
* or below the bounds of the listview. If so, the listview does an appropriate
* upward or downward smooth scroll so as to reveal new items.
*/
public boolean handleMobileCellScroll(Rect r) {
int offset = computeVerticalScrollOffset();
int height = getHeight();
int extent = computeVerticalScrollExtent();
int range = computeVerticalScrollRange();
int hoverViewTop = r.top;
int hoverHeight = r.height();
if (hoverViewTop <= 0 && offset > 0) {
smoothScrollBy(-mSmoothScrollAmountAtEdge, 0);
return true;
}
if (hoverViewTop + hoverHeight >= height && (offset + extent) < range) {
smoothScrollBy(mSmoothScrollAmountAtEdge, 0);
return true;
}
return false;
}
public void setItemsList(List<Object> itemsList) {
mItemsList = itemsList;
}
/*
* Define items which can be moved
* mActiveItemsList == null means all items are movable
*/
public void setActiveItemsList(List<Object> mActiveItemsList) {
this.mActiveItemsList = mActiveItemsList;
}
/**
* This scroll listener is added to the listview in order to handle cell swapping
* when the cell is either at the top or bottom edge of the listview. If the hover
* cell is at either edge of the listview, the listview will begin scrolling. As
* scrolling takes place, the listview continuously checks if new cells became visible
* and determines whether they are potential candidates for a cell swap.
*/
private AbsListView.OnScrollListener mScrollListener = new AbsListView.OnScrollListener() {
private int mPreviousFirstVisibleItem = -1;
private int mPreviousVisibleItemCount = -1;
private int mCurrentFirstVisibleItem;
private int mCurrentVisibleItemCount;
private int mCurrentScrollState;
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
int totalItemCount) {
mCurrentFirstVisibleItem = firstVisibleItem;
mCurrentVisibleItemCount = visibleItemCount;
mPreviousFirstVisibleItem = (mPreviousFirstVisibleItem == -1) ? mCurrentFirstVisibleItem
: mPreviousFirstVisibleItem;
mPreviousVisibleItemCount = (mPreviousVisibleItemCount == -1) ? mCurrentVisibleItemCount
: mPreviousVisibleItemCount;
checkAndHandleFirstVisibleCellChange();
checkAndHandleLastVisibleCellChange();
mPreviousFirstVisibleItem = mCurrentFirstVisibleItem;
mPreviousVisibleItemCount = mCurrentVisibleItemCount;
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
mCurrentScrollState = scrollState;
mScrollState = scrollState;
isScrollCompleted();
}
/**
* This method is in charge of invoking 1 of 2 actions. Firstly, if the listview
* is in a state of scrolling invoked by the hover cell being outside the bounds
* of the listview, then this scrolling event is continued. Secondly, if the hover
* cell has already been released, this invokes the animation for the hover cell
* to return to its correct position after the listview has entered an idle scroll
* state.
*/
private void isScrollCompleted() {
if (mCurrentVisibleItemCount > 0 && mCurrentScrollState == SCROLL_STATE_IDLE) {
if (mCellIsMobile && mIsMobileScrolling) {
handleMobileCellScroll();
} else if (mIsWaitingForScrollFinish) {
touchEventsEnded();
}
}
}
/**
* Determines if the listview scrolled up enough to reveal a new cell at the
* top of the list. If so, then the appropriate parameters are updated.
*/
public void checkAndHandleFirstVisibleCellChange() {
if (mCurrentFirstVisibleItem != mPreviousFirstVisibleItem) {
if (mCellIsMobile && mMobileItemId != INVALID_ID) {
updateNeighborViewsForID(mMobileItemId);
handleCellSwitch();
}
}
}
/**
* Determines if the listview scrolled down enough to reveal a new cell at the
* bottom of the list. If so, then the appropriate parameters are updated.
*/
public void checkAndHandleLastVisibleCellChange() {
int currentLastVisibleItem = mCurrentFirstVisibleItem + mCurrentVisibleItemCount;
int previousLastVisibleItem = mPreviousFirstVisibleItem + mPreviousVisibleItemCount;
if (currentLastVisibleItem != previousLastVisibleItem) {
if (mCellIsMobile && mMobileItemId != INVALID_ID) {
updateNeighborViewsForID(mMobileItemId);
handleCellSwitch();
}
}
}
};
/**
* Returns the most inner view that contains the xy coordinate.
*
* @param v This method gets called recursively. The initial call should be the root view.
* @param x The X location to be tested.
* @param y The Y location to be tested.
* @return Returns the most inner view that contains the XY coordinate or null if no view could be found.
*/
private View findViewAtPositionWithDragIconTag(View v, int x, int y) {
View vXY = null;
if (v instanceof ViewGroup) {
ViewGroup viewGroup = (ViewGroup) v;
for (int i = 0; i < viewGroup.getChildCount(); i++) {
View c = viewGroup.getChildAt(i);
int loc[] = new int[2];
c.getLocationOnScreen(loc);
if ((x >= loc[0] && (x <= (loc[0] + c.getWidth()))) && (y >= loc[1] && (y <= (loc[1] + c.getHeight())))) {
vXY = c;
View viewAtPosition = findViewAtPositionWithDragIconTag(c, x, y);
if ((viewAtPosition != null) && (viewAtPosition.getTag() != null) && viewAtPosition.getTag() instanceof DragIcon) {
vXY = viewAtPosition;
break;
}
}
}
}
return vXY;
}
@Override
protected void onWindowVisibilityChanged(int visibility) {
super.onWindowVisibilityChanged(visibility);
if (dCallbacks != null) {
dCallbacks.onWindowVisibilityChanged(visibility);
}
}
}