/*
* Copyright 2014 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 java.util.Collection;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import android.os.Handler;
import android.view.View;
import android.view.ViewGroup;
import com.nhaarman.listviewanimations.util.AdapterViewUtil;
import com.nhaarman.listviewanimations.util.ListViewWrapper;
import com.nineoldandroids.animation.Animator;
import com.nineoldandroids.animation.AnimatorListenerAdapter;
import com.nineoldandroids.animation.ValueAnimator;
import com.pan.simplepicture.annotations.NonNull;
/**
* A {@link com.nhaarman.listviewanimations.itemmanipulation.swipedismiss.SwipeTouchListener} that directly dismisses the items when swiped.
*/
public class SwipeDismissTouchListener extends SwipeTouchListener {
/**
* The callback which gets notified of dismissed items.
*/
@NonNull
private final OnDismissCallback mCallback;
/**
* The duration of the dismiss animation
*/
private final long mDismissAnimationTime;
/**
* The {@link android.view.View}s that have been dismissed.
*/
@NonNull
private final Collection<View> mDismissedViews = new LinkedList<View>();
/**
* The dismissed positions.
*/
@NonNull
private final List<Integer> mDismissedPositions = new LinkedList<Integer>();
/**
* The number of active dismiss animations.
*/
private int mActiveDismissCount;
/**
* A handler for posting {@link Runnable}s.
*/
@NonNull
private final Handler mHandler = new Handler();
/**
* Constructs a new {@code SwipeDismissTouchListener} for the given {@link android.widget.AbsListView}.
*
* @param listViewWrapper The {@code ListViewWrapper} containing the ListView whose items should be dismissable.
* @param callback The callback to trigger when the user has indicated that he
*/
@SuppressWarnings("UnnecessaryFullyQualifiedName")
public SwipeDismissTouchListener(@NonNull final ListViewWrapper listViewWrapper, @NonNull final OnDismissCallback callback) {
super(listViewWrapper);
mCallback = callback;
mDismissAnimationTime = listViewWrapper.getListView().getContext().getResources().getInteger(android.R.integer.config_shortAnimTime);
}
/**
* Dismisses the {@link android.view.View} corresponding to given position.
* Calling this method has the same effect as manually swiping an item off the screen.
*
* @param position the position of the item in the {@link android.widget.ListAdapter}. Must be visible.
*/
public void dismiss(final int position) {
fling(position);
}
@Override
public void fling(final int position) {
int firstVisiblePosition = getListViewWrapper().getFirstVisiblePosition();
int lastVisiblePosition = getListViewWrapper().getLastVisiblePosition();
if (firstVisiblePosition <= position && position <= lastVisiblePosition) {
super.fling(position);
} else if (position > lastVisiblePosition) {
directDismiss(position);
} else {
dismissAbove(position);
}
}
protected void directDismiss(final int position) {
mDismissedPositions.add(position);
finalizeDismiss();
}
private void dismissAbove(final int position) {
View view = AdapterViewUtil.getViewForPosition(getListViewWrapper(), getListViewWrapper().getFirstVisiblePosition());
if (view != null) {
view.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED), View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
int scrollDistance = view.getMeasuredHeight();
getListViewWrapper().smoothScrollBy(scrollDistance, (int) mDismissAnimationTime);
mHandler.postDelayed(new RestoreScrollRunnable(scrollDistance, position), mDismissAnimationTime);
}
}
@Override
protected void afterCancelSwipe(@NonNull final View view, final int position) {
finalizeDismiss();
}
@Override
protected boolean willLeaveDataSetOnFling(@NonNull final View view, final int position) {
return true;
}
@Override
protected void afterViewFling(@NonNull final View view, final int position) {
performDismiss(view, position);
}
/**
* Animates the dismissed list item to zero-height and fires the dismiss callback when all dismissed list item animations have completed.
*
* @param view the dismissed {@link android.view.View}.
*/
protected void performDismiss(@NonNull final View view, final int position) {
mDismissedViews.add(view);
mDismissedPositions.add(position);
ValueAnimator animator = ValueAnimator.ofInt(view.getHeight(), 1).setDuration(mDismissAnimationTime);
animator.addUpdateListener(new DismissAnimatorUpdateListener(view));
animator.addListener(new DismissAnimatorListener());
animator.start();
mActiveDismissCount++;
}
/**
* If necessary, notifies the {@link OnDismissCallback} to remove dismissed object from the adapter,
* and restores the {@link android.view.View} presentations.
*/
protected void finalizeDismiss() {
if (mActiveDismissCount == 0 && getActiveSwipeCount() == 0) {
restoreViewPresentations(mDismissedViews);
notifyCallback(mDismissedPositions);
mDismissedViews.clear();
mDismissedPositions.clear();
}
}
/**
* Notifies the {@link OnDismissCallback} of dismissed items.
*
* @param dismissedPositions the positions that have been dismissed.
*/
protected void notifyCallback(@NonNull final List<Integer> dismissedPositions) {
if (!dismissedPositions.isEmpty()) {
Collections.sort(dismissedPositions, Collections.reverseOrder());
int[] dismissPositions = new int[dismissedPositions.size()];
int i = 0;
for (Integer dismissedPosition : dismissedPositions) {
dismissPositions[i] = dismissedPosition;
i++;
}
mCallback.onDismiss(getListViewWrapper().getListView(), dismissPositions);
}
}
/**
* Restores the presentation of given {@link android.view.View}s by calling {@link #restoreViewPresentation(android.view.View)}.
*/
protected void restoreViewPresentations(@NonNull final Iterable<View> views) {
for (View view : views) {
restoreViewPresentation(view);
}
}
@Override
protected void restoreViewPresentation(@NonNull final View view) {
super.restoreViewPresentation(view);
ViewGroup.LayoutParams layoutParams = view.getLayoutParams();
layoutParams.height = 0;
view.setLayoutParams(layoutParams);
}
protected int getActiveDismissCount() {
return mActiveDismissCount;
}
public long getDismissAnimationTime() {
return mDismissAnimationTime;
}
/**
* An {@link com.nineoldandroids.animation.ValueAnimator.AnimatorUpdateListener} which applies height animation to given {@link android.view.View}.
*/
private static class DismissAnimatorUpdateListener implements ValueAnimator.AnimatorUpdateListener {
@NonNull
private final View mView;
DismissAnimatorUpdateListener(@NonNull final View view) {
mView = view;
}
@Override
public void onAnimationUpdate(@NonNull final ValueAnimator animation) {
ViewGroup.LayoutParams layoutParams = mView.getLayoutParams();
layoutParams.height = (Integer) animation.getAnimatedValue();
mView.setLayoutParams(layoutParams);
}
}
private class DismissAnimatorListener extends AnimatorListenerAdapter {
@Override
public void onAnimationEnd(@NonNull final Animator animation) {
mActiveDismissCount--;
finalizeDismiss();
}
}
/**
* A {@link Runnable} which applies the dismiss of a position, and restores the scroll position.
*/
private class RestoreScrollRunnable implements Runnable {
private final int mScrollDistance;
private final int mPosition;
/**
* Creates a new {@code RestoreScrollRunnable}.
*
* @param scrollDistance The scroll distance in pixels to restore.
* @param position the position to dismiss
*/
RestoreScrollRunnable(final int scrollDistance, final int position) {
mScrollDistance = scrollDistance;
mPosition = position;
}
@Override
public void run() {
getListViewWrapper().smoothScrollBy(-mScrollDistance, 1);
directDismiss(mPosition);
}
}
}