ZAxisCirclingAnimation--duang duang duang

我们先看看苹果的一个摆动效果，就两个字酷炫。

苹果TV的选中效果

所以安卓能搞吗，答案是肯定的啦

import android.graphics.Camera;
import android.graphics.Matrix;
import android.view.animation.Animation;
import android.view.animation.LinearInterpolator;
import android.view.animation.Transformation;
//Z轴画圆动画
public class ZAxisCirclingAnimation extends Animation {
    int centerX, centerY;
    Camera camera = new Camera();
    float range = 9f;
    @Override
    public void initialize(int width, int height, int parentWidth,
                           int parentHeight) {
        super.initialize(width, height, parentWidth, parentHeight);
        //获取中心点坐标
        centerX = width / 2;
        centerY = height / 2;
        //动画执行时间  自行定义
        setDuration(4000);
        setInterpolator(new LinearInterpolator());
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        final Matrix matrix = t.getMatrix();
        camera.save();
        //放大时间
        float timeAmplifier;
        if (0 <= interpolatedTime && interpolatedTime <= 0.25f) {
            timeAmplifier = 4f * interpolatedTime;
            camera.rotateX( (float)Math.toDegrees(Math.asin((1f-timeAmplifier)/range)));
            camera.rotateY( (float)Math.toDegrees(Math.asin(timeAmplifier/range)));
        } else if (0.25f < interpolatedTime && interpolatedTime <= 0.5f) {
            timeAmplifier = 4f * (interpolatedTime-0.25f);
            camera.rotateX( -((float)Math.toDegrees(Math.asin(timeAmplifier/range))));
            camera.rotateY( (float)Math.toDegrees(Math.asin((1f-timeAmplifier)/range)));
        } else if (0.5f < interpolatedTime && interpolatedTime <= 0.75f) {
            timeAmplifier = 4f * (interpolatedTime-0.5f);
            camera.rotateX( -((float)Math.toDegrees(Math.asin((1f-timeAmplifier)/range))));
            camera.rotateY( -((float)Math.toDegrees(Math.asin(timeAmplifier/range))));
        } else if (0.75f < interpolatedTime && interpolatedTime <= 1) {
            timeAmplifier = 4f * (interpolatedTime-0.75f);
            camera.rotateX( (float)Math.toDegrees(Math.asin(timeAmplifier/range)));
            camera.rotateY( -((float)Math.toDegrees(Math.asin((1f-timeAmplifier)/range))));
        }
        //把我们的摄像头加在变换矩阵上
        camera.getMatrix(matrix);
        //设置翻转中心点
        matrix.preTranslate(-centerX, -centerY);
        matrix.postTranslate(centerX, centerY);
        camera.restore();
    }
}

达到的效果：

安卓下的效果

额，怎么感觉很像有点不同呢.........
问题不大好吗 它的动作要领在线就行
---分割线---
------2018-03-29------最终效果实现。

托马斯回旋选中效果

备注:使用此动画的View记得开抗锯齿。

有一点要注意下，就是用阴影来对抗锯齿。这个旋转动画的锯齿太严重了， view做了抗锯齿也很严重。我突发奇想，锯齿的来源是绘制运动的直线导致的。我们让它边缘是很多的点那不就解决了。