/*
* Copyright 2012 Roman Nurik
* Copyright 2013 Frankie Sardo
* 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.contextualundo;
import android.graphics.Rect;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import com.nhaarman.listviewanimations.itemmanipulation.swipedismiss.DismissableManager;
import com.nhaarman.listviewanimations.itemmanipulation.swipedismiss.SwipeOnTouchListener;
import com.nhaarman.listviewanimations.util.AdapterViewUtil;
import com.nineoldandroids.animation.Animator;
import com.nineoldandroids.animation.AnimatorListenerAdapter;
import static com.nineoldandroids.view.ViewHelper.setAlpha;
import static com.nineoldandroids.view.ViewHelper.setTranslationX;
import static com.nineoldandroids.view.ViewPropertyAnimator.animate;
/**
* An {@link OnTouchListener} for the {@link ContextualUndoAdapter}. Don't use
* this class directly, use ContextualUndoAdapter to wrap your
* {@link BaseAdapter}s.
*/
public class ContextualUndoListViewTouchListener implements SwipeOnTouchListener {
// Cached ViewConfiguration and system-wide constant values
private final int mSlop;
private final int mMinFlingVelocity;
private final int mMaxFlingVelocity;
private final long mAnimationTime;
// Fixed properties
private final AbsListView mListView;
private final Callback mCallback;
private int mViewWidth = 1; // 1 and not 0 to prevent dividing by zero
// Transient properties
private float mDownX;
private float mDownY;
private boolean mSwiping;
private VelocityTracker mVelocityTracker;
private int mDownPosition;
private View mDownView;
private boolean mPaused;
private boolean mDisallowSwipe;
private boolean mIsParentHorizontalScrollContainer;
private int mResIdOfTouchChild;
private boolean mTouchChildTouched;
private DismissableManager mDismissableManager;
public interface Callback {
void onViewSwiped(long dismissViewItemId, int dismissPosition);
void onListScrolled();
}
public ContextualUndoListViewTouchListener(final AbsListView listView, final Callback callback) {
ViewConfiguration vc = ViewConfiguration.get(listView.getContext());
mSlop = vc.getScaledTouchSlop();
mMinFlingVelocity = vc.getScaledMinimumFlingVelocity();
mMaxFlingVelocity = vc.getScaledMaximumFlingVelocity();
mAnimationTime = listView.getContext().getResources().getInteger(android.R.integer.config_shortAnimTime);
mListView = listView;
mCallback = callback;
}
public void setEnabled(final boolean enabled) {
mPaused = !enabled;
}
/**
* 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;
}
public AbsListView.OnScrollListener makeScrollListener() {
return new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(final AbsListView absListView, final int scrollState) {
setEnabled(scrollState != AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL);
if (mPaused) {
mCallback.onListScrolled();
}
if (scrollState != AbsListView.OnScrollListener.SCROLL_STATE_IDLE) {
mDisallowSwipe = true;
}
}
@Override
public void onScroll(final AbsListView absListView, final int firstVisibleItem, final int visibleItemCount,
final int totalItemCount) {
}
};
}
@Override
public boolean onTouch(final View view, final MotionEvent motionEvent) {
if (mViewWidth < 2) {
mViewWidth = mListView.getWidth();
}
boolean result;
switch (motionEvent.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
result = handleDownEvent(view, motionEvent);
break;
case MotionEvent.ACTION_MOVE:
result = handleMoveEvent(view, motionEvent);
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
result = handleUpCancelEvent(view, motionEvent);
break;
default:
result = false;
}
return result;
}
private boolean handleDownEvent(final View view, final MotionEvent motionEvent) {
mDisallowSwipe = false;
if (mPaused) {
return false;
}
// 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 child;
for (int i = 0; i < childCount; i++) {
child = mListView.getChildAt(i);
child.getHitRect(rect);
if (rect.contains(x, y)) {
mDownView = child;
break;
}
}
if (mDownView != null && mDownView instanceof ContextualUndoView) {
mDownX = motionEvent.getRawX();
mDownY = motionEvent.getRawY();
int downPosition = AdapterViewUtil.getPositionForView(mListView, mDownView);
if (mDismissableManager != null) {
long downId = mListView.getAdapter().getItemId(downPosition);
if (!mDismissableManager.isDismissable(downId, downPosition)) {
/* Cancel, not dismissable */
return false;
}
}
mTouchChildTouched = !mIsParentHorizontalScrollContainer && mResIdOfTouchChild == 0;
if (mResIdOfTouchChild != 0) {
mIsParentHorizontalScrollContainer = false;
final View childView = mDownView.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);
}
mDownY = motionEvent.getRawY();
mDownPosition = AdapterViewUtil.getPositionForView(mListView, mDownView);
if (mTouchChildTouched) {
mVelocityTracker = VelocityTracker.obtain();
mVelocityTracker.addMovement(motionEvent);
} else {
mVelocityTracker = null;
}
}
view.onTouchEvent(motionEvent);
return true;
}
@SuppressWarnings("UnusedParameters")
private boolean handleMoveEvent(final View view, final MotionEvent motionEvent) {
if (mVelocityTracker == null || mPaused) {
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);
cancelEvent.recycle();
}
if (mSwiping) {
setTranslationX(mDownView, deltaX);
//noinspection MagicNumber
setAlpha(mDownView, Math.max(0f, Math.min(1f, 1f - 2f * Math.abs(deltaX) / mViewWidth)));
return true;
}
return false;
}
@SuppressWarnings("UnusedParameters")
private boolean handleUpCancelEvent(final View view, final MotionEvent motionEvent) {
mDisallowSwipe = false;
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;
final float absDeltaX = Math.abs(deltaX);
if (absDeltaX > mViewWidth / 2) {
dismiss = true;
dismissRight = deltaX > 0;
} else if (mMinFlingVelocity <= velocityX && velocityX <= mMaxFlingVelocity && velocityY < velocityX && absDeltaX > mSlop) {
dismiss = true;
dismissRight = mVelocityTracker.getXVelocity() > 0;
}
if (dismiss) {
// dismiss
final long itemId = ((ContextualUndoView) mDownView).getItemId();
// before animation ends
final int downPosition = mDownPosition;
animate(mDownView).translationX(dismissRight ? mViewWidth : -mViewWidth).alpha(0).setDuration(mAnimationTime).setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(final Animator animation) {
mCallback.onViewSwiped(itemId, downPosition);
}
});
} else {
// cancel
animate(mDownView).translationX(0).alpha(1).setDuration(mAnimationTime).setListener(null);
}
mVelocityTracker.recycle();
mVelocityTracker = null;
mDownX = 0;
mDownView = null;
mDownPosition = AdapterView.INVALID_POSITION;
mSwiping = false;
return false;
}
@Override
public boolean isSwiping() {
return mSwiping;
}
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;
}
void setIsParentHorizontalScrollContainer(final boolean isParentHorizontalScrollContainer) {
mIsParentHorizontalScrollContainer = mResIdOfTouchChild == 0 && isParentHorizontalScrollContainer;
}
void setTouchChild(final int childResId) {
mResIdOfTouchChild = childResId;
if (childResId != 0) {
setIsParentHorizontalScrollContainer(false);
}
}
}