自定义Animation中如何让组件移动至屏幕右下角

 

package com.demo;

import android.graphics.Camera;
import android.graphics.Matrix;
import android.view.animation.Animation;
import android.view.animation.LinearInterpolator;
import android.view.animation.Transformation;

public class MyAnimation extends Animation {

    private int parentWidth;
    private int parentHeight;
    private float objectWidth;
    private float objectHeight;
    private Camera camera;

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        // TODO Auto-generated method stub
        super.applyTransformation(interpolatedTime, t);
        Matrix matrix=t.getMatrix();
        camera.save();
        camera.getMatrix(matrix);  //必须写在preTranslate postTranslate方法之前否则达不到想要的效果

        matrix.preTranslate(0,0); //动画起始点,默认左上角
        matrix.postTranslate((parentWidth-objectWidth)*interpolatedTime, (parentHeight-objectHeight)*interpolatedTime);
        /*
        matrix.preTranslate(parentWidth/2,parentHeight/2);
        matrix.postTranslate((parentWidth/2-objectWidth)*interpolatedTime, (parentHeight/2-objectHeight)*interpolatedTime);
        */

        camera.restore();


    }

    @Override
    public void initialize(int width, int height, int parentWidth, //width,height表目标组件的尺寸，
            int parentHeight) {                                    //parentWidth,parentHeight表目的组件的父组件的尺寸
        // TODO Auto-generated method stub
        super.initialize(width, height, parentWidth, parentHeight);
        setDuration(5000);
        setFillAfter(false); //设置是否保存动画后的位置,false表示动画后恢复到初始位置
        objectHeight=height;
        objectWidth=width;
        this.parentWidth=parentWidth;
        this.parentHeight=parentHeight;
        camera=new Camera();
        setInterpolator(new LinearInterpolator()); //设置动画播放速率
    }

}