NineOldAndroidsDemos 学习(7) BouncingBalls

BouncingBalls这个demo做的很漂亮 实现 了更加 复杂的形变 和 上下运动

/* * Copyright (C) 2010 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.jakewharton.nineoldandroids.sample.apidemos;import java.util.ArrayList;import android.app.Activity;import android.content.Context;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.RadialGradient;import android.graphics.Shader;import android.graphics.drawable.ShapeDrawable;import android.graphics.drawable.shapes.OvalShape;import android.os.Bundle;import android.view.MotionEvent;import android.view.View;import android.view.animation.AccelerateInterpolator;import android.view.animation.DecelerateInterpolator;import android.widget.LinearLayout;import com.nineoldandroids.animation.Animator;import com.nineoldandroids.animation.AnimatorListenerAdapter;import com.nineoldandroids.animation.AnimatorSet;import com.nineoldandroids.animation.ArgbEvaluator;import com.nineoldandroids.animation.ObjectAnimator;import com.nineoldandroids.animation.ValueAnimator;import com.jakewharton.nineoldandroids.sample.R;public class BouncingBalls extends Activity {    /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.bouncing_balls);        LinearLayout container = (LinearLayout) findViewById(R.id.container);        container.addView(new MyAnimationView(this));    }    public class MyAnimationView extends View {        private static final int RED = 0xffFF8080;        private static final int BLUE = 0xff8080FF;        private static final int CYAN = 0xff80ffff;        private static final int GREEN = 0xff80ff80;        public final ArrayList<ShapeHolder> balls = new ArrayList<ShapeHolder>();        AnimatorSet animation = null;        public MyAnimationView(Context context) {            super(context);            // Animate background color            // Note that setting the background color will automatically invalidate the            // view, so that the animated color, and the bouncing balls, get redisplayed on            // every frame of the animation.            //设置view的背景             ValueAnimator colorAnim = ObjectAnimator.ofInt(this, "backgroundColor", RED, BLUE);            colorAnim.setDuration(3000);            colorAnim.setEvaluator(new ArgbEvaluator());            colorAnim.setRepeatCount(ValueAnimator.INFINITE);            colorAnim.setRepeatMode(ValueAnimator.REVERSE);            colorAnim.start();        }        @Override        public boolean onTouchEvent(MotionEvent event) {            if (event.getAction() != MotionEvent.ACTION_DOWN &&                    event.getAction() != MotionEvent.ACTION_MOVE) {                return false;            }            ShapeHolder newBall = addBall(event.getX(), event.getY());            // Bouncing animation with squash and stretch            float startY = newBall.getY();            float endY = getHeight() - 50f;            float h = (float)getHeight();            float eventY = event.getY();            int duration = (int)(500 * ((h - eventY)/h));//不过是为了让y大的 弹的执行的时间少一点 y小的执行的时间长一点            ValueAnimator bounceAnim = ObjectAnimator.ofFloat(newBall, "y", startY, endY); //从上向下运动            bounceAnim.setDuration(duration);            bounceAnim.setInterpolator(new AccelerateInterpolator());            ValueAnimator squashAnim1 = ObjectAnimator.ofFloat(newBall, "x", newBall.getX(),                    newBall.getX() - 25f);//在小球变扁的时候 需要让他居中            squashAnim1.setDuration(duration/4);            squashAnim1.setRepeatCount(1);            squashAnim1.setRepeatMode(ValueAnimator.REVERSE);            squashAnim1.setInterpolator(new DecelerateInterpolator());            ValueAnimator squashAnim2 = ObjectAnimator.ofFloat(newBall, "width", newBall.getWidth(),//设置小球的宽度,                    newBall.getWidth() + 50);            squashAnim2.setDuration(duration/4);            squashAnim2.setRepeatCount(1);            squashAnim2.setRepeatMode(ValueAnimator.REVERSE);            squashAnim2.setInterpolator(new DecelerateInterpolator());            ValueAnimator stretchAnim1 = ObjectAnimator.ofFloat(newBall, "y", endY,                    endY + 25f);            stretchAnim1.setDuration(duration/4);            stretchAnim1.setRepeatCount(1);            stretchAnim1.setInterpolator(new DecelerateInterpolator());            stretchAnim1.setRepeatMode(ValueAnimator.REVERSE);            ValueAnimator stretchAnim2 = ObjectAnimator.ofFloat(newBall, "height",                    newBall.getHeight(), newBall.getHeight() - 25);//小球高度的变化            stretchAnim2.setDuration(duration/4);            stretchAnim2.setRepeatCount(1);            stretchAnim2.setInterpolator(new DecelerateInterpolator());            stretchAnim2.setRepeatMode(ValueAnimator.REVERSE);            ValueAnimator bounceBackAnim = ObjectAnimator.ofFloat(newBall, "y", endY,//返回远点                    startY);            bounceBackAnim.setDuration(duration);            bounceBackAnim.setInterpolator(new DecelerateInterpolator());            // Sequence the down/squash&stretch/up animations            AnimatorSet bouncer = new AnimatorSet();            bouncer.play(bounceAnim).before(squashAnim1);//点击的时候先从上往下运动            bouncer.play(squashAnim1).with(squashAnim2).with(stretchAnim1).with(stretchAnim2);//触底后开始 使小球 变扁 (squashAnim2 +stretchAnim2 )居中(stretchAnim1 , squashAnim1) //            bouncer.play(squashAnim1).with(stretchAnim1);//            bouncer.play(squashAnim1).with(stretchAnim2);            bouncer.play(bounceBackAnim).after(stretchAnim2);//弹回远点            // Fading animation - remove the ball when the animation is done            ValueAnimator fadeAnim = ObjectAnimator.ofFloat(newBall, "alpha", 1f, 0f);            fadeAnim.setDuration(250);            fadeAnim.addListener(new AnimatorListenerAdapter() {                @Override                public void onAnimationEnd(Animator animation) {                    balls.remove(((ObjectAnimator)animation).getTarget());                }            });            // Sequence the two animations to play one after the other            AnimatorSet animatorSet = new AnimatorSet();            animatorSet.play(bouncer).before(fadeAnim);            // Start the animation            animatorSet.start();            return true;        }        private ShapeHolder addBall(float x, float y) {            OvalShape circle = new OvalShape();            circle.resize(50f, 50f);            ShapeDrawable drawable = new ShapeDrawable(circle);            ShapeHolder shapeHolder = new ShapeHolder(drawable);            shapeHolder.setX(x - 25f);            shapeHolder.setY(y - 25f);            int red = (int)(Math.random() * 255);            int green = (int)(Math.random() * 255);            int blue = (int)(Math.random() * 255);            int color = 0xff000000 | red << 16 | green << 8 | blue;            Paint paint = drawable.getPaint(); //new Paint(Paint.ANTI_ALIAS_FLAG);            int darkColor = 0xff000000 | red/4 << 16 | green/4 << 8 | blue/4;            RadialGradient gradient = new RadialGradient(37.5f, 12.5f,                    50f, color, darkColor, Shader.TileMode.CLAMP);            paint.setShader(gradient);            shapeHolder.setPaint(paint);            balls.add(shapeHolder);            return shapeHolder;        }        @Override        protected void onDraw(Canvas canvas) {            for (int i = 0; i < balls.size(); ++i) {                ShapeHolder shapeHolder = balls.get(i);                canvas.save();                canvas.translate(shapeHolder.getX(), shapeHolder.getY());                shapeHolder.getShape().draw(canvas);                canvas.restore();            }        }    }}