自定义动画

创建自定义动画

1、覆盖父类的initialize方法，实现初始化工作。

2、实现applyTransformation的逻辑。

 @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        super.applyTransformation(interpolatedTime, t);
    }

第一个参数：差值器时间因子，范围0-1.0。

第二个参数：矩阵的封装类。可以用来获得当前的矩阵对象，通过改版matrix来实现效果的动画。

 final Matrix matrix = t.getMatrix();

模拟电视开机

public class MyAnimation extends Animation {
    private int mCenterX;
    private int mCenterY;
    private Camera camera = new Camera();

    @Override
    public void initialize(int width, int height, int parentWidth, int parentHeight) {
        super.initialize(width, height, parentWidth, parentHeight);
        setDuration(500);
        setFillAfter(true);
        setInterpolator(new LinearInterpolator());
        mCenterX = width / 2;
        mCenterY = height / 2;
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        super.applyTransformation(interpolatedTime, t);
        final Matrix matrix = t.getMatrix();
        camera.save();
        if (interpolatedTime < 0.8) {
            matrix.preScale(1 + 0.625f * interpolatedTime, 1 - interpolatedTime / 0.8f + 0.01f, mCenterX, mCenterY);
        } else {
            matrix.preScale(7.5f * (1 - interpolatedTime), 0.01f, mCenterX, mCenterY);
        }
        camera.restore();
    }
}