1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.example.android.apis.animation; 18 19 // Need the following import to get access to the app resources, since this 20 // class is in a sub-package. 21 import android.graphics.drawable.ColorDrawable; 22 import com.example.android.apis.R; 23 24 import android.animation.*; 25 import android.app.Activity; 26 import android.content.Context; 27 import android.graphics.Canvas; 28 import android.graphics.Paint; 29 import android.graphics.RadialGradient; 30 import android.graphics.Shader; 31 import android.graphics.drawable.ShapeDrawable; 32 import android.graphics.drawable.shapes.OvalShape; 33 import android.os.Bundle; 34 import android.view.MotionEvent; 35 import android.view.View; 36 import android.view.animation.AccelerateInterpolator; 37 import android.view.animation.DecelerateInterpolator; 38 import android.widget.LinearLayout; 39 40 import java.util.ArrayList; 41 42 43 public class BouncingBalls extends Activity { 44 /** Called when the activity is first created. */ 45 @Override onCreate(Bundle savedInstanceState)46 public void onCreate(Bundle savedInstanceState) { 47 super.onCreate(savedInstanceState); 48 setContentView(R.layout.bouncing_balls); 49 LinearLayout container = (LinearLayout) findViewById(R.id.container); 50 container.addView(new MyAnimationView(this)); 51 } 52 53 public class MyAnimationView extends View { 54 55 private static final int RED = 0xffFF8080; 56 private static final int BLUE = 0xff8080FF; 57 private static final int CYAN = 0xff80ffff; 58 private static final int GREEN = 0xff80ff80; 59 60 public final ArrayList<ShapeHolder> balls = new ArrayList<ShapeHolder>(); 61 AnimatorSet animation = null; 62 MyAnimationView(Context context)63 public MyAnimationView(Context context) { 64 super(context); 65 66 // Animate background color 67 // Note that setting the background color will automatically invalidate the 68 // view, so that the animated color, and the bouncing balls, get redisplayed on 69 // every frame of the animation. 70 ValueAnimator colorAnim = ObjectAnimator.ofInt(this, "backgroundColor", RED, BLUE); 71 colorAnim.setDuration(3000); 72 colorAnim.setEvaluator(new ArgbEvaluator()); 73 colorAnim.setRepeatCount(ValueAnimator.INFINITE); 74 colorAnim.setRepeatMode(ValueAnimator.REVERSE); 75 colorAnim.start(); 76 } 77 78 @Override onTouchEvent(MotionEvent event)79 public boolean onTouchEvent(MotionEvent event) { 80 if (event.getAction() != MotionEvent.ACTION_DOWN && 81 event.getAction() != MotionEvent.ACTION_MOVE) { 82 return false; 83 } 84 ShapeHolder newBall = addBall(event.getX(), event.getY()); 85 86 // Bouncing animation with squash and stretch 87 float startY = newBall.getY(); 88 float endY = getHeight() - 50f; 89 float h = (float)getHeight(); 90 float eventY = event.getY(); 91 int duration = (int)(500 * ((h - eventY)/h)); 92 ValueAnimator bounceAnim = ObjectAnimator.ofFloat(newBall, "y", startY, endY); 93 bounceAnim.setDuration(duration); 94 bounceAnim.setInterpolator(new AccelerateInterpolator()); 95 ValueAnimator squashAnim1 = ObjectAnimator.ofFloat(newBall, "x", newBall.getX(), 96 newBall.getX() - 25f); 97 squashAnim1.setDuration(duration/4); 98 squashAnim1.setRepeatCount(1); 99 squashAnim1.setRepeatMode(ValueAnimator.REVERSE); 100 squashAnim1.setInterpolator(new DecelerateInterpolator()); 101 ValueAnimator squashAnim2 = ObjectAnimator.ofFloat(newBall, "width", newBall.getWidth(), 102 newBall.getWidth() + 50); 103 squashAnim2.setDuration(duration/4); 104 squashAnim2.setRepeatCount(1); 105 squashAnim2.setRepeatMode(ValueAnimator.REVERSE); 106 squashAnim2.setInterpolator(new DecelerateInterpolator()); 107 ValueAnimator stretchAnim1 = ObjectAnimator.ofFloat(newBall, "y", endY, 108 endY + 25f); 109 stretchAnim1.setDuration(duration/4); 110 stretchAnim1.setRepeatCount(1); 111 stretchAnim1.setInterpolator(new DecelerateInterpolator()); 112 stretchAnim1.setRepeatMode(ValueAnimator.REVERSE); 113 ValueAnimator stretchAnim2 = ObjectAnimator.ofFloat(newBall, "height", 114 newBall.getHeight(), newBall.getHeight() - 25); 115 stretchAnim2.setDuration(duration/4); 116 stretchAnim2.setRepeatCount(1); 117 stretchAnim2.setInterpolator(new DecelerateInterpolator()); 118 stretchAnim2.setRepeatMode(ValueAnimator.REVERSE); 119 ValueAnimator bounceBackAnim = ObjectAnimator.ofFloat(newBall, "y", endY, 120 startY); 121 bounceBackAnim.setDuration(duration); 122 bounceBackAnim.setInterpolator(new DecelerateInterpolator()); 123 // Sequence the down/squash&stretch/up animations 124 AnimatorSet bouncer = new AnimatorSet(); 125 bouncer.play(bounceAnim).before(squashAnim1); 126 bouncer.play(squashAnim1).with(squashAnim2); 127 bouncer.play(squashAnim1).with(stretchAnim1); 128 bouncer.play(squashAnim1).with(stretchAnim2); 129 bouncer.play(bounceBackAnim).after(stretchAnim2); 130 131 // Fading animation - remove the ball when the animation is done 132 ValueAnimator fadeAnim = ObjectAnimator.ofFloat(newBall, "alpha", 1f, 0f); 133 fadeAnim.setDuration(250); 134 fadeAnim.addListener(new AnimatorListenerAdapter() { 135 @Override 136 public void onAnimationEnd(Animator animation) { 137 balls.remove(((ObjectAnimator)animation).getTarget()); 138 139 } 140 }); 141 142 // Sequence the two animations to play one after the other 143 AnimatorSet animatorSet = new AnimatorSet(); 144 animatorSet.play(bouncer).before(fadeAnim); 145 146 // Start the animation 147 animatorSet.start(); 148 149 return true; 150 } 151 addBall(float x, float y)152 private ShapeHolder addBall(float x, float y) { 153 OvalShape circle = new OvalShape(); 154 circle.resize(50f, 50f); 155 ShapeDrawable drawable = new ShapeDrawable(circle); 156 ShapeHolder shapeHolder = new ShapeHolder(drawable); 157 shapeHolder.setX(x - 25f); 158 shapeHolder.setY(y - 25f); 159 int red = (int)(Math.random() * 255); 160 int green = (int)(Math.random() * 255); 161 int blue = (int)(Math.random() * 255); 162 int color = 0xff000000 | red << 16 | green << 8 | blue; 163 Paint paint = drawable.getPaint(); //new Paint(Paint.ANTI_ALIAS_FLAG); 164 int darkColor = 0xff000000 | red/4 << 16 | green/4 << 8 | blue/4; 165 RadialGradient gradient = new RadialGradient(37.5f, 12.5f, 166 50f, color, darkColor, Shader.TileMode.CLAMP); 167 paint.setShader(gradient); 168 shapeHolder.setPaint(paint); 169 balls.add(shapeHolder); 170 return shapeHolder; 171 } 172 173 @Override onDraw(Canvas canvas)174 protected void onDraw(Canvas canvas) { 175 for (int i = 0; i < balls.size(); ++i) { 176 ShapeHolder shapeHolder = balls.get(i); 177 canvas.save(); 178 canvas.translate(shapeHolder.getX(), shapeHolder.getY()); 179 shapeHolder.getShape().draw(canvas); 180 canvas.restore(); 181 } 182 } 183 } 184 }