samples/devbytes/animation/ListViewRemovalAnimation/src/com/example/android/listviewremovalanimation/ListViewRemovalAnimation.java - platform/development - Git at Google

 /*
  * 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.
  */

 package com.example.android.listviewremovalanimation;

 import java.util.ArrayList;
 import java.util.HashMap;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewConfiguration;
 import android.view.ViewTreeObserver;
 import android.widget.ListView;

 /**
  * This example shows how to use a swipe effect to remove items from a ListView,
  * and how to use animations to complete the swipe as well as to animate the other
  * items in the list into their final places.
  *
  * Watch the associated video for this demo on the DevBytes channel of developer.android.com
  * or on YouTube at https://www.youtube.com/watch?v=NewCSg2JKLk.
  */
 public class ListViewRemovalAnimation extends Activity {

     StableArrayAdapter mAdapter;
     ListView mListView;
     BackgroundContainer mBackgroundContainer;
     boolean mSwiping = false;
     boolean mItemPressed = false;
     HashMap<Long, Integer> mItemIdTopMap = new HashMap<Long, Integer>();

     private static final int SWIPE_DURATION = 250;
     private static final int MOVE_DURATION = 150;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_list_view_deletion);

         mBackgroundContainer = (BackgroundContainer) findViewById(R.id.listViewBackground);
         mListView = (ListView) findViewById(R.id.listview);
         android.util.Log.d("Debug", "d=" + mListView.getDivider());
         final ArrayList<String> cheeseList = new ArrayList<String>();
         for (int i = 0; i < Cheeses.sCheeseStrings.length; ++i) {
             cheeseList.add(Cheeses.sCheeseStrings[i]);
         }
         mAdapter = new StableArrayAdapter(this,R.layout.opaque_text_view, cheeseList,
                 mTouchListener);
         mListView.setAdapter(mAdapter);
     }

     /**
      * Handle touch events to fade/move dragged items as they are swiped out
      */
     private View.OnTouchListener mTouchListener = new View.OnTouchListener() {

         float mDownX;
         private int mSwipeSlop = -1;

         @Override
         public boolean onTouch(final View v, MotionEvent event) {
             if (mSwipeSlop < 0) {
                 mSwipeSlop = ViewConfiguration.get(ListViewRemovalAnimation.this).
                         getScaledTouchSlop();
             }
             switch (event.getAction()) {
             case MotionEvent.ACTION_DOWN:
                 if (mItemPressed) {
                     // Multi-item swipes not handled
                     return false;
                 }
                 mItemPressed = true;
                 mDownX = event.getX();
                 break;
             case MotionEvent.ACTION_CANCEL:
                 v.setAlpha(1);
                 v.setTranslationX(0);
                 mItemPressed = false;
                 break;
             case MotionEvent.ACTION_MOVE:
                 {
                     float x = event.getX() + v.getTranslationX();
                     float deltaX = x - mDownX;
                     float deltaXAbs = Math.abs(deltaX);
                     if (!mSwiping) {
                         if (deltaXAbs > mSwipeSlop) {
                             mSwiping = true;
                             mListView.requestDisallowInterceptTouchEvent(true);
                             mBackgroundContainer.showBackground(v.getTop(), v.getHeight());
                         }
                     }
                     if (mSwiping) {
                         v.setTranslationX((x - mDownX));
                         v.setAlpha(1 - deltaXAbs / v.getWidth());
                     }
                 }
                 break;
             case MotionEvent.ACTION_UP:
                 {
                     // User let go - figure out whether to animate the view out, or back into place
                     if (mSwiping) {
                         float x = event.getX() + v.getTranslationX();
                         float deltaX = x - mDownX;
                         float deltaXAbs = Math.abs(deltaX);
                         float fractionCovered;
                         float endX;
                         float endAlpha;
                         final boolean remove;
                         if (deltaXAbs > v.getWidth() / 4) {
                             // Greater than a quarter of the width - animate it out
                             fractionCovered = deltaXAbs / v.getWidth();
                             endX = deltaX < 0 ? -v.getWidth() : v.getWidth();
                             endAlpha = 0;
                             remove = true;
                         } else {
                             // Not far enough - animate it back
                             fractionCovered = 1 - (deltaXAbs / v.getWidth());
                             endX = 0;
                             endAlpha = 1;
                             remove = false;
                         }
                         // Animate position and alpha of swiped item
                         // NOTE: This is a simplified version of swipe behavior, for the
                         // purposes of this demo about animation. A real version should use
                         // velocity (via the VelocityTracker class) to send the item off or
                         // back at an appropriate speed.
                         long duration = (int) ((1 - fractionCovered) * SWIPE_DURATION);
                         mListView.setEnabled(false);
                         v.animate().setDuration(duration).
                                 alpha(endAlpha).translationX(endX).
                                 withEndAction(new Runnable() {
                                     @Override
                                     public void run() {
                                         // Restore animated values
                                         v.setAlpha(1);
                                         v.setTranslationX(0);
                                         if (remove) {
                                             animateRemoval(mListView, v);
                                         } else {
                                             mBackgroundContainer.hideBackground();
                                             mSwiping = false;
                                             mListView.setEnabled(true);
                                         }
                                     }
                                 });
                     }
                 }
                 mItemPressed = false;
                 break;
             default:
                 return false;
             }
             return true;
         }
     };

     /**
      * This method animates all other views in the ListView container (not including ignoreView)
      * into their final positions. It is called after ignoreView has been removed from the
      * adapter, but before layout has been run. The approach here is to figure out where
      * everything is now, then allow layout to run, then figure out where everything is after
      * layout, and then to run animations between all of those start/end positions.
      */
     private void animateRemoval(final ListView listview, View viewToRemove) {
         int firstVisiblePosition = listview.getFirstVisiblePosition();
         for (int i = 0; i < listview.getChildCount(); ++i) {
             View child = listview.getChildAt(i);
             if (child != viewToRemove) {
                 int position = firstVisiblePosition + i;
                 long itemId = mAdapter.getItemId(position);
                 mItemIdTopMap.put(itemId, child.getTop());
             }
         }
         // Delete the item from the adapter
         int position = mListView.getPositionForView(viewToRemove);
         mAdapter.remove(mAdapter.getItem(position));

         final ViewTreeObserver observer = listview.getViewTreeObserver();
         observer.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
             public boolean onPreDraw() {
                 observer.removeOnPreDrawListener(this);
                 boolean firstAnimation = true;
                 int firstVisiblePosition = listview.getFirstVisiblePosition();
                 for (int i = 0; i < listview.getChildCount(); ++i) {
                     final View child = listview.getChildAt(i);
                     int position = firstVisiblePosition + i;
                     long itemId = mAdapter.getItemId(position);
                     Integer startTop = mItemIdTopMap.get(itemId);
                     int top = child.getTop();
                     if (startTop != null) {
                         if (startTop != top) {
                             int delta = startTop - top;
                             child.setTranslationY(delta);
                             child.animate().setDuration(MOVE_DURATION).translationY(0);
                             if (firstAnimation) {
                                 child.animate().withEndAction(new Runnable() {
                                     public void run() {
                                         mBackgroundContainer.hideBackground();
                                         mSwiping = false;
                                         mListView.setEnabled(true);
                                     }
                                 });
                                 firstAnimation = false;
                             }
                         }
                     } else {
                         // Animate new views along with the others. The catch is that they did not
                         // exist in the start state, so we must calculate their starting position
                         // based on neighboring views.
                         int childHeight = child.getHeight() + listview.getDividerHeight();
                         startTop = top + (i > 0 ? childHeight : -childHeight);
                         int delta = startTop - top;
                         child.setTranslationY(delta);
                         child.animate().setDuration(MOVE_DURATION).translationY(0);
                         if (firstAnimation) {
                             child.animate().withEndAction(new Runnable() {
                                 public void run() {
                                     mBackgroundContainer.hideBackground();
                                     mSwiping = false;
                                     mListView.setEnabled(true);
                                 }
                             });
                             firstAnimation = false;
                         }
                     }
                 }
                 mItemIdTopMap.clear();
                 return true;
             }
         });
     }

 }
	/*
	* 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.
	*/

	package com.example.android.listviewremovalanimation;

	import java.util.ArrayList;
	import java.util.HashMap;

	import android.app.Activity;
	import android.os.Bundle;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.ViewConfiguration;
	import android.view.ViewTreeObserver;
	import android.widget.ListView;

	/**
	* This example shows how to use a swipe effect to remove items from a ListView,
	* and how to use animations to complete the swipe as well as to animate the other
	* items in the list into their final places.
	*
	* Watch the associated video for this demo on the DevBytes channel of developer.android.com
	* or on YouTube at https://www.youtube.com/watch?v=NewCSg2JKLk.
	*/
	public class ListViewRemovalAnimation extends Activity {

	StableArrayAdapter mAdapter;
	ListView mListView;
	BackgroundContainer mBackgroundContainer;
	boolean mSwiping = false;
	boolean mItemPressed = false;
	HashMap<Long, Integer> mItemIdTopMap = new HashMap<Long, Integer>();

	private static final int SWIPE_DURATION = 250;
	private static final int MOVE_DURATION = 150;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	setContentView(R.layout.activity_list_view_deletion);

	mBackgroundContainer = (BackgroundContainer) findViewById(R.id.listViewBackground);
	mListView = (ListView) findViewById(R.id.listview);
	android.util.Log.d("Debug", "d=" + mListView.getDivider());
	final ArrayList<String> cheeseList = new ArrayList<String>();
	for (int i = 0; i < Cheeses.sCheeseStrings.length; ++i) {
	cheeseList.add(Cheeses.sCheeseStrings[i]);
	}
	mAdapter = new StableArrayAdapter(this,R.layout.opaque_text_view, cheeseList,
	mTouchListener);
	mListView.setAdapter(mAdapter);
	}

	/**
	* Handle touch events to fade/move dragged items as they are swiped out
	*/
	private View.OnTouchListener mTouchListener = new View.OnTouchListener() {

	float mDownX;
	private int mSwipeSlop = -1;

	@Override
	public boolean onTouch(final View v, MotionEvent event) {
	if (mSwipeSlop < 0) {
	mSwipeSlop = ViewConfiguration.get(ListViewRemovalAnimation.this).
	getScaledTouchSlop();
	}
	switch (event.getAction()) {
	case MotionEvent.ACTION_DOWN:
	if (mItemPressed) {
	// Multi-item swipes not handled
	return false;
	}
	mItemPressed = true;
	mDownX = event.getX();
	break;
	case MotionEvent.ACTION_CANCEL:
	v.setAlpha(1);
	v.setTranslationX(0);
	mItemPressed = false;
	break;
	case MotionEvent.ACTION_MOVE:
	{
	float x = event.getX() + v.getTranslationX();
	float deltaX = x - mDownX;
	float deltaXAbs = Math.abs(deltaX);
	if (!mSwiping) {
	if (deltaXAbs > mSwipeSlop) {
	mSwiping = true;
	mListView.requestDisallowInterceptTouchEvent(true);
	mBackgroundContainer.showBackground(v.getTop(), v.getHeight());
	}
	}
	if (mSwiping) {
	v.setTranslationX((x - mDownX));
	v.setAlpha(1 - deltaXAbs / v.getWidth());
	}
	}
	break;
	case MotionEvent.ACTION_UP:
	{
	// User let go - figure out whether to animate the view out, or back into place
	if (mSwiping) {
	float x = event.getX() + v.getTranslationX();
	float deltaX = x - mDownX;
	float deltaXAbs = Math.abs(deltaX);
	float fractionCovered;
	float endX;
	float endAlpha;
	final boolean remove;
	if (deltaXAbs > v.getWidth() / 4) {
	// Greater than a quarter of the width - animate it out
	fractionCovered = deltaXAbs / v.getWidth();
	endX = deltaX < 0 ? -v.getWidth() : v.getWidth();
	endAlpha = 0;
	remove = true;
	} else {
	// Not far enough - animate it back
	fractionCovered = 1 - (deltaXAbs / v.getWidth());
	endX = 0;
	endAlpha = 1;
	remove = false;
	}
	// Animate position and alpha of swiped item
	// NOTE: This is a simplified version of swipe behavior, for the
	// purposes of this demo about animation. A real version should use
	// velocity (via the VelocityTracker class) to send the item off or
	// back at an appropriate speed.
	long duration = (int) ((1 - fractionCovered) * SWIPE_DURATION);
	mListView.setEnabled(false);
	v.animate().setDuration(duration).
	alpha(endAlpha).translationX(endX).
	withEndAction(new Runnable() {
	@Override
	public void run() {
	// Restore animated values
	v.setAlpha(1);
	v.setTranslationX(0);
	if (remove) {
	animateRemoval(mListView, v);
	} else {
	mBackgroundContainer.hideBackground();
	mSwiping = false;
	mListView.setEnabled(true);
	}
	}
	});
	}
	}
	mItemPressed = false;
	break;
	default:
	return false;
	}
	return true;
	}
	};

	/**
	* This method animates all other views in the ListView container (not including ignoreView)
	* into their final positions. It is called after ignoreView has been removed from the
	* adapter, but before layout has been run. The approach here is to figure out where
	* everything is now, then allow layout to run, then figure out where everything is after
	* layout, and then to run animations between all of those start/end positions.
	*/
	private void animateRemoval(final ListView listview, View viewToRemove) {
	int firstVisiblePosition = listview.getFirstVisiblePosition();
	for (int i = 0; i < listview.getChildCount(); ++i) {
	View child = listview.getChildAt(i);
	if (child != viewToRemove) {
	int position = firstVisiblePosition + i;
	long itemId = mAdapter.getItemId(position);
	mItemIdTopMap.put(itemId, child.getTop());
	}
	}
	// Delete the item from the adapter
	int position = mListView.getPositionForView(viewToRemove);
	mAdapter.remove(mAdapter.getItem(position));

	final ViewTreeObserver observer = listview.getViewTreeObserver();
	observer.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
	public boolean onPreDraw() {
	observer.removeOnPreDrawListener(this);
	boolean firstAnimation = true;
	int firstVisiblePosition = listview.getFirstVisiblePosition();
	for (int i = 0; i < listview.getChildCount(); ++i) {
	final View child = listview.getChildAt(i);
	int position = firstVisiblePosition + i;
	long itemId = mAdapter.getItemId(position);
	Integer startTop = mItemIdTopMap.get(itemId);
	int top = child.getTop();
	if (startTop != null) {
	if (startTop != top) {
	int delta = startTop - top;
	child.setTranslationY(delta);
	child.animate().setDuration(MOVE_DURATION).translationY(0);
	if (firstAnimation) {
	child.animate().withEndAction(new Runnable() {
	public void run() {
	mBackgroundContainer.hideBackground();
	mSwiping = false;
	mListView.setEnabled(true);
	}
	});
	firstAnimation = false;
	}
	}
	} else {
	// Animate new views along with the others. The catch is that they did not
	// exist in the start state, so we must calculate their starting position
	// based on neighboring views.
	int childHeight = child.getHeight() + listview.getDividerHeight();
	startTop = top + (i > 0 ? childHeight : -childHeight);
	int delta = startTop - top;
	child.setTranslationY(delta);
	child.animate().setDuration(MOVE_DURATION).translationY(0);
	if (firstAnimation) {
	child.animate().withEndAction(new Runnable() {
	public void run() {
	mBackgroundContainer.hideBackground();
	mSwiping = false;
	mListView.setEnabled(true);
	}
	});
	firstAnimation = false;
	}
	}
	}
	mItemIdTopMap.clear();
	return true;
	}
	});
	}

	}