package com.imooc.customanim;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.view.animation.Animation;
import android.view.animation.BounceInterpolator;
import android.view.animation.Transformation;
public class CustomAnim extends Animation {
private int mCenterWidth;
private int mCenterHeight;
private Camera mCamera = new Camera();
private float mRotateY = 0.0f;
@Override
public void initialize(int width,
int height,
int parentWidth,
int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
// 设置默认时长
setDuration(2000);
// 动画结束后保留状态
setFillAfter(true);
// 设置默认插值器
setInterpolator(new BounceInterpolator());
mCenterWidth = width / 2;
mCenterHeight = height / 2;
}
// 暴露接口-设置旋转角度
public void setRotateY(float rotateY) {
mRotateY = rotateY;
}
@Override
protected void applyTransformation(
float interpolatedTime,
Transformation t) {
final Matrix matrix = t.getMatrix();
mCamera.save();
// 使用Camera设置旋转的角度
mCamera.rotateY(mRotateY * interpolatedTime);
// 将旋转变换作用到matrix上
mCamera.getMatrix(matrix);
mCamera.restore();
// 通过pre方法设置矩阵作用前的偏移量来改变旋转中心
matrix.preTranslate(mCenterWidth, mCenterHeight);
matrix.postTranslate(-mCenterWidth, -mCenterHeight);
}
}