// THIS IS A BETA! I DON'T RECOMMEND USING IT IN PRODUCTION CODE JUST YET
/*
* Copyright 2012 Roman Nurik
* Copyright 2013 Niek Haarman
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.nhaarman.listviewanimations.itemmanipulation.swipedismiss;
import android.annotation.SuppressLint;
import android.graphics.Rect;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.ListView;
import com.nhaarman.listviewanimations.itemmanipulation.OnDismissCallback;
import com.nhaarman.listviewanimations.util.AdapterViewUtil;
import com.nineoldandroids.animation.Animator;
import com.nineoldandroids.animation.AnimatorListenerAdapter;
import com.nineoldandroids.animation.ValueAnimator;
import com.nineoldandroids.view.ViewHelper;
import com.nineoldandroids.view.ViewPropertyAnimator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import static com.nineoldandroids.view.ViewPropertyAnimator.animate;
/**
* A {@link android.view.View.OnTouchListener} that makes the list items in a
* {@link ListView} dismissable. {@link ListView} is given special treatment
* because by default it handles touches for its list items... i.e. it's in
* charge of drawing the pressed state (the list selector), handling list item
* clicks, etc.
*
* For performance reasons, do not use this class directly, but use the {@link com.nhaarman.listviewanimations.itemmanipulation.swipedismiss.SwipeDismissAdapter}.
*/
@SuppressLint("Recycle")
public class SwipeDismissListViewTouchListener implements SwipeOnTouchListener {
private static final int MIN_FLING_VELOCITY_FACTOR = 16;
// Cached ViewConfiguration and system-wide constant values
private final int mSlop;
private final int mMinFlingVelocity;
private final int mMaxFlingVelocity;
protected long mAnimationTime;
// Fixed properties
private final AbsListView mListView;
private final OnDismissCallback mCallback;
private int mViewWidth = 1; // 1 and not 0 to prevent dividing by zero
// Transient properties
protected List<PendingDismissData> mPendingDismisses = new ArrayList<PendingDismissData>();
private int mDismissAnimationRefCount = 0;
private float mDownX;
private float mDownY;
private boolean mSwiping;
private VelocityTracker mVelocityTracker;
private PendingDismissData mCurrentDismissData;
private int mVirtualListCount = -1;
private boolean mDisallowSwipe;
private boolean mIsParentHorizontalScrollContainer;
private int mResIdOfTouchChild;
private boolean mTouchChildTouched;
private DismissableManager mDismissableManager;
/**
* Constructs a new swipe-to-dismiss touch listener for the given list view.
*
* @param listView
* The list view whose items should be dismissable.
* @param callback
* The callback to trigger when the user has indicated that she
* would like to dismiss one or more list items.
*/
public SwipeDismissListViewTouchListener(final AbsListView listView, final OnDismissCallback callback, final SwipeOnScrollListener onScroll) {
ViewConfiguration vc = ViewConfiguration.get(listView.getContext());
mSlop = vc.getScaledTouchSlop();
mMinFlingVelocity = vc.getScaledMinimumFlingVelocity() * MIN_FLING_VELOCITY_FACTOR;
mMaxFlingVelocity = vc.getScaledMaximumFlingVelocity();
mAnimationTime = listView.getContext().getResources().getInteger(android.R.integer.config_shortAnimTime);
mListView = listView;
mCallback = callback;
onScroll.setTouchListener(this);
mListView.setOnScrollListener(onScroll);
}
public void disallowSwipe() {
mDisallowSwipe = true;
}
@SuppressWarnings("UnusedDeclaration")
public void allowSwipe() {
mDisallowSwipe = false;
}
/**
* Set the {@link com.nhaarman.listviewanimations.itemmanipulation.swipedismiss.DismissableManager} to specify which views can or cannot be swiped.
* @param dismissableManager null for no restrictions.
*/
@SuppressWarnings("UnusedDeclaration")
public void setDismissableManager(final DismissableManager dismissableManager) {
mDismissableManager = dismissableManager;
}
@Override
public boolean onTouch(final View view, final MotionEvent motionEvent) {
if (mVirtualListCount == -1) {
mVirtualListCount = mListView.getAdapter().getCount();
}
if (mViewWidth < 2) {
mViewWidth = mListView.getWidth();
}
switch (motionEvent.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
mDisallowSwipe = false;
view.onTouchEvent(motionEvent);
return handleDownEvent(motionEvent);
case MotionEvent.ACTION_MOVE:
return handleMoveEvent(motionEvent);
case MotionEvent.ACTION_CANCEL:
return handleCancelEvent(motionEvent);
case MotionEvent.ACTION_UP:
mDisallowSwipe = false;
mTouchChildTouched = false;
return handleUpEvent(motionEvent);
}
return false;
}
@Override
public boolean isSwiping() {
return mSwiping;
}
/**
* Factory to allow override of dismiss data
*/
protected PendingDismissData createPendingDismissData(final int position, final View view) {
return new PendingDismissData(position, view);
}
private boolean handleDownEvent(final MotionEvent motionEvent) {
// Find the child view that was touched (perform a hit test)
Rect rect = new Rect();
int childCount = mListView.getChildCount();
int[] listViewCoords = new int[2];
mListView.getLocationOnScreen(listViewCoords);
int x = (int) motionEvent.getRawX() - listViewCoords[0];
int y = (int) motionEvent.getRawY() - listViewCoords[1];
View downView = null;
for (int i = 0; i < childCount && downView == null; i++) {
View child = mListView.getChildAt(i);
child.getHitRect(rect);
if (rect.contains(x, y)) {
downView = child;
}
}
if (downView != null) {
mDownX = motionEvent.getRawX();
mDownY = motionEvent.getRawY();
int downPosition = AdapterViewUtil.getPositionForView(mListView, downView);
if (mDismissableManager != null) {
long downId = mListView.getAdapter().getItemId(downPosition);
if (!mDismissableManager.isDismissable(downId, downPosition)) {
/* Cancel, not dismissable */
return false;
}
}
mCurrentDismissData = createPendingDismissData(downPosition, downView);
if (mPendingDismisses.contains(mCurrentDismissData) || downPosition >= mVirtualListCount) {
// Cancel, we're already processing this position
mCurrentDismissData = null;
return false;
} else {
mTouchChildTouched = !mIsParentHorizontalScrollContainer && mResIdOfTouchChild == 0;
if (mResIdOfTouchChild != 0) {
mIsParentHorizontalScrollContainer = false;
final View childView = downView.findViewById(mResIdOfTouchChild);
if (childView != null) {
final Rect childRect = getChildViewRect(mListView, childView);
if (childRect.contains((int) motionEvent.getX(), (int) motionEvent.getY())) {
mTouchChildTouched = true;
mListView.requestDisallowInterceptTouchEvent(true);
}
}
}
if (mIsParentHorizontalScrollContainer) {
// Do it now and don't wait until the user moves more than
// the slop factor.
mTouchChildTouched = true;
mListView.requestDisallowInterceptTouchEvent(true);
}
mVelocityTracker = VelocityTracker.obtain();
mVelocityTracker.addMovement(motionEvent);
}
}
return true;
}
private Rect getChildViewRect(final View parentView, View childView) {
final Rect childRect = new Rect(childView.getLeft(), childView.getTop(), childView.getRight(), childView.getBottom());
if (parentView == childView) {
return childRect;
}
ViewGroup parent;
while ((parent = (ViewGroup) childView.getParent()) != parentView) {
childRect.offset(parent.getLeft(), parent.getTop());
childView = parent;
}
return childRect;
}
private boolean handleMoveEvent(final MotionEvent motionEvent) {
if (mVelocityTracker == null) {
return false;
}
mVelocityTracker.addMovement(motionEvent);
float deltaX = motionEvent.getRawX() - mDownX;
float deltaY = motionEvent.getRawY() - mDownY;
if (mTouchChildTouched && !mDisallowSwipe && Math.abs(deltaX) > mSlop && Math.abs(deltaX) > Math.abs(deltaY)) {
mSwiping = true;
mListView.requestDisallowInterceptTouchEvent(true);
// Cancel ListView's touch (un-highlighting the item)
MotionEvent cancelEvent = MotionEvent.obtain(motionEvent);
cancelEvent.setAction(MotionEvent.ACTION_CANCEL | motionEvent.getActionIndex() << MotionEvent.ACTION_POINTER_INDEX_SHIFT);
mListView.onTouchEvent(cancelEvent);
}
if (mSwiping) {
ViewHelper.setTranslationX(mCurrentDismissData.view, deltaX);
//noinspection MagicNumber
ViewHelper.setAlpha(mCurrentDismissData.view, Math.max(0f, Math.min(1f, 1f - 2f * Math.abs(deltaX) / mViewWidth)));
return true;
}
return false;
}
@SuppressWarnings("UnusedParameters")
private boolean handleCancelEvent(final MotionEvent motionEvent) {
if (mVelocityTracker == null) {
return false;
}
if (mCurrentDismissData != null && mSwiping) {
ViewPropertyAnimator.animate(mCurrentDismissData.view)
.translationX(0)
.alpha(1)
.setDuration(mAnimationTime)
.setListener(null);
}
mVelocityTracker.recycle();
mVelocityTracker = null;
mDownX = 0;
mDownY = 0;
mCurrentDismissData = null;
mSwiping = false;
return false;
}
private boolean handleUpEvent(final MotionEvent motionEvent) {
if (mVelocityTracker == null) {
return false;
}
float deltaX = motionEvent.getRawX() - mDownX;
mVelocityTracker.addMovement(motionEvent);
mVelocityTracker.computeCurrentVelocity(1000);
float velocityX = Math.abs(mVelocityTracker.getXVelocity());
float velocityY = Math.abs(mVelocityTracker.getYVelocity());
boolean dismiss = false;
boolean dismissRight = false;
if (Math.abs(deltaX) > mViewWidth / 2) {
dismiss = true;
dismissRight = deltaX > 0;
} else if (mMinFlingVelocity <= velocityX && velocityX <= mMaxFlingVelocity && velocityY < velocityX) {
dismiss = true;
dismissRight = mVelocityTracker.getXVelocity() > 0;
}
if (mSwiping) {
if (dismiss) {
// mDownView gets null'd before animation ends
final PendingDismissData pendingDismissData = mCurrentDismissData;
++mDismissAnimationRefCount;
animate(mCurrentDismissData.view).translationX(dismissRight ? mViewWidth : -mViewWidth).alpha(0).setDuration(mAnimationTime).setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(final Animator animation) {
onDismiss(pendingDismissData);
}
});
mVirtualListCount--;
mPendingDismisses.add(mCurrentDismissData);
} else {
// cancel
animate(mCurrentDismissData.view).translationX(0).alpha(1).setDuration(mAnimationTime).setListener(null);
}
}
mVelocityTracker.recycle();
mVelocityTracker = null;
mDownX = 0;
mDownY = 0;
mCurrentDismissData = null;
mSwiping = false;
return false;
}
protected class PendingDismissData implements Comparable<PendingDismissData> {
public final int position;
public final View view;
public PendingDismissData(final int position, final View view) {
this.position = position;
this.view = view;
}
@Override
public int compareTo(final PendingDismissData other) {
// Sort by descending position
return other.position - position;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + position;
return result;
}
@Override
public boolean equals(final Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (((Object) this).getClass() != obj.getClass())
return false;
PendingDismissData other = (PendingDismissData) obj;
return position == other.position;
}
}
protected void onDismiss(final PendingDismissData data) {
// default behaviour
performDismiss(data);
}
protected void performDismiss(final PendingDismissData data) {
// Animate the dismissed list item to zero-height and fire the
// dismiss callback when all dismissed list item animations have
// completed.
final ViewGroup.LayoutParams lp = data.view.getLayoutParams();
final int originalHeight = data.view.getHeight();
ValueAnimator animator = ValueAnimator.ofInt(originalHeight, 1).setDuration(mAnimationTime);
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(final ValueAnimator valueAnimator) {
lp.height = (Integer) valueAnimator.getAnimatedValue();
data.view.setLayoutParams(lp);
}
});
animator.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(final Animator animation) {
finalizeDismiss();
}
});
animator.start();
}
/**
* Here you can manage dismissed View.
*/
protected void recycleDismissedViewsItems(final List<PendingDismissData> pendingDismisses) {
ViewGroup.LayoutParams lp;
for (final PendingDismissData pendingDismiss : pendingDismisses) {
// Reset view presentation
ViewHelper.setAlpha(pendingDismiss.view, 1f);
ViewHelper.setTranslationX(pendingDismiss.view, 0);
lp = pendingDismiss.view.getLayoutParams();
lp.height = 0;
pendingDismiss.view.setLayoutParams(lp);
}
}
protected void finalizeDismiss() {
--mDismissAnimationRefCount;
if (mDismissAnimationRefCount == 0) {
// No active animations, process all pending dismisses.
// Sort by descending position
Collections.sort(mPendingDismisses);
int[] dismissPositions = new int[mPendingDismisses.size()];
for (int i = mPendingDismisses.size() - 1; i >= 0; i--) {
dismissPositions[i] = mPendingDismisses.get(i).position;
}
mCallback.onDismiss(mListView, dismissPositions);
recycleDismissedViewsItems(mPendingDismisses);
mPendingDismisses.clear();
}
}
void setIsParentHorizontalScrollContainer(final boolean isParentHorizontalScrollContainer) {
mIsParentHorizontalScrollContainer = mResIdOfTouchChild == 0 && isParentHorizontalScrollContainer;
}
void setTouchChild(final int childResId) {
mResIdOfTouchChild = childResId;
if (childResId != 0) {
setIsParentHorizontalScrollContainer(false);
}
}
public void notifyDataSetChanged() {
mVirtualListCount = mListView.getAdapter().getCount();
}
}