AnimationSeeking.java revision d9855a8dbed211de6e1c1cf55e20201349c40432 
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
17package 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.
21import android.animation.Animator;
22import com.example.android.apis.R;
23
24import java.util.ArrayList;
25
26import android.animation.ValueAnimator;
27import android.animation.ObjectAnimator;
28import android.animation.AnimatorSet;
29import android.app.Activity;
30import android.content.Context;
31import android.graphics.Canvas;
32import android.graphics.Paint;
33import android.graphics.RadialGradient;
34import android.graphics.Shader;
35import android.graphics.drawable.ShapeDrawable;
36import android.graphics.drawable.shapes.OvalShape;
37import android.os.Bundle;
38import android.view.View;
39import android.view.animation.BounceInterpolator;
40import android.widget.Button;
41import android.widget.LinearLayout;
42import 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 */
49public 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
66            @Override
67            public void onClick(View v) {
68                animView.startAnimation();
69            }
70        });
71
72        mSeekBar = (SeekBar) findViewById(R.id.seekBar);
73        mSeekBar.setMax(DURATION);
74        mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
75
76            @Override
77            public void onStopTrackingTouch(SeekBar seekBar) {
78            }
79
80            @Override
81            public void onStartTrackingTouch(SeekBar seekBar) {
82            }
83
84            @Override
85            public void onProgressChanged(SeekBar seekBar, int progress,
86                    boolean fromUser) {
87                // prevent seeking on app creation
88                if (animView.getHeight() != 0) {
89                    animView.seek(progress);
90                }
91            }
92        });
93    }
94
95    public class MyAnimationView extends View implements ValueAnimator.AnimatorUpdateListener, Animator.AnimatorListener {
96
97        private static final int RED = 0xffFF8080;
98        private static final int BLUE = 0xff8080FF;
99        private static final int CYAN = 0xff80ffff;
100        private static final int GREEN = 0xff80ff80;
101        private static final float BALL_SIZE = 100f;
102
103        public final ArrayList<ShapeHolder> balls = new ArrayList<ShapeHolder>();
104        AnimatorSet animation = null;
105        ValueAnimator bounceAnim = null;
106        ShapeHolder ball = null;
107
108        public MyAnimationView(Context context) {
109            super(context);
110            ball = addBall(200, 0);
111        }
112
113        private void createAnimation() {
114            if (bounceAnim == null) {
115                bounceAnim = new ObjectAnimator(1500, ball, "y",
116                        ball.getY(), getHeight() - BALL_SIZE);
117                bounceAnim.setInterpolator(new BounceInterpolator());
118                bounceAnim.addUpdateListener(this);
119            }
120        }
121
122        public void startAnimation() {
123            createAnimation();
124            bounceAnim.start();
125        }
126
127        public void seek(long seekTime) {
128            createAnimation();
129            bounceAnim.setCurrentPlayTime(seekTime);
130        }
131
132        private ShapeHolder addBall(float x, float y) {
133            OvalShape circle = new OvalShape();
134            circle.resize(BALL_SIZE, BALL_SIZE);
135            ShapeDrawable drawable = new ShapeDrawable(circle);
136            ShapeHolder shapeHolder = new ShapeHolder(drawable);
137            shapeHolder.setX(x);
138            shapeHolder.setY(y);
139            int red = (int)(100 + Math.random() * 155);
140            int green = (int)(100 + Math.random() * 155);
141            int blue = (int)(100 + Math.random() * 155);
142            int color = 0xff000000 | red << 16 | green << 8 | blue;
143            Paint paint = drawable.getPaint();
144            int darkColor = 0xff000000 | red/4 << 16 | green/4 << 8 | blue/4;
145            RadialGradient gradient = new RadialGradient(37.5f, 12.5f,
146                    50f, color, darkColor, Shader.TileMode.CLAMP);
147            paint.setShader(gradient);
148            shapeHolder.setPaint(paint);
149            balls.add(shapeHolder);
150            return shapeHolder;
151        }
152
153        @Override
154        protected void onDraw(Canvas canvas) {
155            canvas.translate(ball.getX(), ball.getY());
156            ball.getShape().draw(canvas);
157        }
158
159        public void onAnimationUpdate(ValueAnimator animation) {
160            invalidate();
161            long playtime = bounceAnim.getCurrentPlayTime();
162            //mSeekBar.setProgress((int)playtime);
163        }
164
165        @Override
166        public void onAnimationCancel(Animator animation) {
167        }
168
169        @Override
170        public void onAnimationEnd(Animator animation) {
171            balls.remove(((ObjectAnimator)animation).getTarget());
172
173        }
174
175        @Override
176        public void onAnimationRepeat(Animator animation) {
177        }
178
179        @Override
180        public void onAnimationStart(Animator animation) {
181        }
182    }
183}