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      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.animation.Animator;
     22 import com.example.android.apis.R;
     23 
     24 import java.util.ArrayList;
     25 
     26 import android.animation.ValueAnimator;
     27 import android.animation.ObjectAnimator;
     28 import android.animation.AnimatorSet;
     29 import android.app.Activity;
     30 import android.content.Context;
     31 import android.graphics.Canvas;
     32 import android.graphics.Paint;
     33 import android.graphics.RadialGradient;
     34 import android.graphics.Shader;
     35 import android.graphics.drawable.ShapeDrawable;
     36 import android.graphics.drawable.shapes.OvalShape;
     37 import android.os.Bundle;
     38 import android.view.View;
     39 import android.view.animation.BounceInterpolator;
     40 import android.widget.Button;
     41 import android.widget.LinearLayout;
     42 import android.widget.SeekBar;
     43 
     44 /**
     45  * This application demonstrates the seeking capability of ValueAnimator. The SeekBar in the
     46  * UI allows you to set the position of the animation. Pressing the Run button will play from
     47  * the current position of the animation.
     48  */
     49 public class AnimationSeeking extends Activity {
     50 
     51     private static final int DURATION = 1500;
     52     private SeekBar mSeekBar;
     53 
     54     /** Called when the activity is first created. */
     55     @Override
     56     public void onCreate(Bundle savedInstanceState) {
     57         super.onCreate(savedInstanceState);
     58         setContentView(R.layout.animation_seeking);
     59         LinearLayout container = (LinearLayout) findViewById(R.id.container);
     60         final MyAnimationView animView = new MyAnimationView(this);
     61         container.addView(animView);
     62 
     63         Button starter = (Button) findViewById(R.id.startButton);
     64         starter.setOnClickListener(new View.OnClickListener() {
     65             public void onClick(View v) {
     66                 animView.startAnimation();
     67             }
     68         });
     69 
     70         mSeekBar = (SeekBar) findViewById(R.id.seekBar);
     71         mSeekBar.setMax(DURATION);
     72         mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
     73             public void onStopTrackingTouch(SeekBar seekBar) {
     74             }
     75 
     76             public void onStartTrackingTouch(SeekBar seekBar) {
     77             }
     78 
     79             public void onProgressChanged(SeekBar seekBar, int progress,
     80                     boolean fromUser) {
     81                 // prevent seeking on app creation
     82                 if (animView.getHeight() != 0) {
     83                     animView.seek(progress);
     84                 }
     85             }
     86         });
     87     }
     88 
     89     public class MyAnimationView extends View implements ValueAnimator.AnimatorUpdateListener, Animator.AnimatorListener {
     90 
     91         private static final int RED = 0xffFF8080;
     92         private static final int BLUE = 0xff8080FF;
     93         private static final int CYAN = 0xff80ffff;
     94         private static final int GREEN = 0xff80ff80;
     95         private static final float BALL_SIZE = 100f;
     96 
     97         public final ArrayList<ShapeHolder> balls = new ArrayList<ShapeHolder>();
     98         AnimatorSet animation = null;
     99         ValueAnimator bounceAnim = null;
    100         ShapeHolder ball = null;
    101 
    102         public MyAnimationView(Context context) {
    103             super(context);
    104             ball = addBall(200, 0);
    105         }
    106 
    107         private void createAnimation() {
    108             if (bounceAnim == null) {
    109                 bounceAnim = ObjectAnimator.ofFloat(ball, "y",
    110                         ball.getY(), getHeight() - BALL_SIZE).setDuration(1500);
    111                 bounceAnim.setInterpolator(new BounceInterpolator());
    112                 bounceAnim.addUpdateListener(this);
    113             }
    114         }
    115 
    116         public void startAnimation() {
    117             createAnimation();
    118             bounceAnim.start();
    119         }
    120 
    121         public void seek(long seekTime) {
    122             createAnimation();
    123             bounceAnim.setCurrentPlayTime(seekTime);
    124         }
    125 
    126         private ShapeHolder addBall(float x, float y) {
    127             OvalShape circle = new OvalShape();
    128             circle.resize(BALL_SIZE, BALL_SIZE);
    129             ShapeDrawable drawable = new ShapeDrawable(circle);
    130             ShapeHolder shapeHolder = new ShapeHolder(drawable);
    131             shapeHolder.setX(x);
    132             shapeHolder.setY(y);
    133             int red = (int)(100 + Math.random() * 155);
    134             int green = (int)(100 + Math.random() * 155);
    135             int blue = (int)(100 + Math.random() * 155);
    136             int color = 0xff000000 | red << 16 | green << 8 | blue;
    137             Paint paint = drawable.getPaint();
    138             int darkColor = 0xff000000 | red/4 << 16 | green/4 << 8 | blue/4;
    139             RadialGradient gradient = new RadialGradient(37.5f, 12.5f,
    140                     50f, color, darkColor, Shader.TileMode.CLAMP);
    141             paint.setShader(gradient);
    142             shapeHolder.setPaint(paint);
    143             balls.add(shapeHolder);
    144             return shapeHolder;
    145         }
    146 
    147         @Override
    148         protected void onDraw(Canvas canvas) {
    149             canvas.translate(ball.getX(), ball.getY());
    150             ball.getShape().draw(canvas);
    151         }
    152 
    153         public void onAnimationUpdate(ValueAnimator animation) {
    154             invalidate();
    155             long playtime = bounceAnim.getCurrentPlayTime();
    156             //mSeekBar.setProgress((int)playtime);
    157         }
    158 
    159         public void onAnimationCancel(Animator animation) {
    160         }
    161 
    162         public void onAnimationEnd(Animator animation) {
    163             balls.remove(((ObjectAnimator)animation).getTarget());
    164 
    165         }
    166 
    167         public void onAnimationRepeat(Animator animation) {
    168         }
    169 
    170         public void onAnimationStart(Animator animation) {
    171         }
    172     }
    173 }