android 通过贝塞尔曲线 实现爱心点赞功能

Android 通过贝塞尔曲线 实现爱心点赞功能：
  ValueAnimatior:
核心功能：
    已知起点p0, 终p3，中间点 p1、p2  通过贝塞尔曲线 计算路径中各个点
案例1：  重力抛物线  
案例2：  爱心点赞功能

核心代码：LoveLayout 

package mk.denganzhi.com.zhiwenku;
import java.util.Random;
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.AnimatorSet;
import android.animation.ObjectAnimator;
import android.animation.ValueAnimator;
import android.animation.ValueAnimator.AnimatorUpdateListener;
import android.content.Context;
import android.graphics.PointF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import mk.denganzhi.com.zhiwenku.BezierEvaluator;
import mk.denganzhi.com.zhiwenku.R;
public class LoveLayout extends RelativeLayout {
    Drawable[] drawables = new Drawable[3];
    private Random random = new Random();
    private int dHeight;
    private int dWidth;
    private LayoutParams params;
    private int mWidth;
    private int mHeight;
    public LoveLayout(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }
    public LoveLayout(Context context) {
        super(context);
        init();
    }
    public LoveLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        // 必须在测量完毕以后才知道控件高度、和宽度
        mWidth = getMeasuredWidth();
        mHeight = getMeasuredHeight();
    }
    private void init() {
        //准备图片集合
        drawables[0] = getResources().getDrawable(R.drawable.red);
        drawables[1] = getResources().getDrawable(R.drawable.yellow);
        drawables[2] = getResources().getDrawable(R.drawable.blue);
        //得到图片的原始高度
        dWidth = drawables[0].getIntrinsicWidth();
        dHeight = drawables[0].getIntrinsicHeight();
        params = new LayoutParams(dWidth, dHeight);
        //将iv添加到父容器底部、水平居中位置
        params.addRule(CENTER_HORIZONTAL);
        params.addRule(ALIGN_PARENT_BOTTOM);
    }
    // 1. 第一步:  绘制ImageView 心形
    public void addLoveIcon(){
        //添加心形，并开始执行动画
        final ImageView iv = new ImageView(getContext());
        iv.setImageDrawable(drawables[random.nextInt(3)]);
        //将iv添加到父容器底部、水平居中位置
        iv.setLayoutParams(params);
        addView(iv);
        //开始属性动画：平移、透明度渐变、缩放动画
        AnimatorSet set = getAnimator(iv);
        //监听动画执行完毕，将iv移除或者复用
        set.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationEnd(Animator animation) {
                super.onAnimationEnd(animation);
                removeView(iv);
            }
        });
        set.start();
    }
    // 得到一个iv的动画集合
    private AnimatorSet getAnimator(ImageView iv) {
        //平移、透明度渐变、缩放动画
        //1.alpha动画
        ObjectAnimator alpha = ObjectAnimator.ofFloat(iv, "alpha", 0.3f,1f);
        //2.缩放动画
        ObjectAnimator scaleX = ObjectAnimator.ofFloat(iv, "scaleX", 0.3f,1f);
        ObjectAnimator scaleY = ObjectAnimator.ofFloat(iv, "scaleY", 0.3f,1f);
        //三个动画同时执行
        AnimatorSet enter = new AnimatorSet();
        enter.setDuration(600);
        enter.playTogether(alpha,scaleX,scaleY);
//		enter.setTarget(iv);
        //设置平移的曲线动画---贝塞尔曲线
        // 2. 第二步启动估值器
        ValueAnimator bezierAnimator = getBezierValueAnimator(iv);
        AnimatorSet set = new AnimatorSet();
        //同时依次执行 实现属性动画
        set.playSequentially(enter,bezierAnimator);
        set.setTarget(iv);
        return set;
    }
    //得到一个贝塞尔曲线动画
    private ValueAnimator getBezierValueAnimator(final ImageView iv) {
        //根据贝塞尔公式确定四个点（起始点p0，拐点1p1，拐点2p2，终点p3）
        PointF pointF0 = new PointF((mWidth-dWidth)/2, mHeight-dHeight);
        PointF pointF3 = new PointF(random.nextInt(mWidth), 0);
        PointF pointF1 = getPointF(1);
        PointF pointF2 = getPointF(2);
        BezierEvaluator evaluator = new BezierEvaluator(pointF1,pointF2);
        ValueAnimator animator = ValueAnimator.ofObject(evaluator, pointF0,pointF3);
        animator.addUpdateListener(new AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator animation) {
                PointF pointF = (PointF) animation.getAnimatedValue();
//                iv.setX(pointF.x);
//                iv.setY(pointF.y);
                iv.setX(pointF.x);
                iv.setY(pointF.y);
                Log.e("denganzhi1","坐标是:x"+ pointF.x +"  y:" + pointF.y);
                iv.setAlpha(1-animation.getAnimatedFraction());//1~0 百分比
            }
        });
        animator.setDuration(10000);
        return animator;
    }
    private PointF getPointF(int i) {
        PointF pointF = new PointF();
        pointF.x = random.nextInt(mWidth);
        if(i==1){
            pointF.y = random.nextInt(mHeight/2)+mHeight/2;
        }else{
            pointF.y = random.nextInt(mHeight/2);
        }
        return pointF;
    }
}

package mk.denganzhi.com.zhiwenku;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
    private LoveLayout loveLayout;
    MyBazierLayout  myBazierLayout;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        loveLayout = (LoveLayout)findViewById(R.id.loveLayout);
        myBazierLayout = findViewById(R.id.loveLayout2);
    }
    public void  start(View view){
        loveLayout.addLoveIcon();
      //  myBazierLayout.addLoveIcon();
    }
    public void translate(View view) {
     //   myBazierLayout.translateFun();
    }
}