- save restore Canvas保存和还原
- drawLine drawColor 绘制图形
- translate scale 平移 旋转 坐标轴梗着跟着变
- clipRect clipPath 裁剪画布
android.graphics.Region.Op.DIFFERENCE 用于决定前后两块画布之间如何配合展示比如子交补并
先绘制水晶球，画布变成了圆形，然后绘制矩形，根据高度不停的绘制实现动画效果
圆形的水晶球装水的过程，水平线一点点的升高
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
wellPath.reset();
wellPath.addCircle(getWidth() / 2, getHeight() / 2, getWidth() * 2 / 5, Path.Direction.CCW);
canvas.clipPath(wellPath);
canvas.drawColor(getResources().getColor(R.color.well));
//子交补并
// waterRect.top = (int) startY;
// canvas.drawRect(waterRect,waterPaint);
//http://blog.csdn.net/eyishion/article/details/53728913
canvas.save();
waterRect.top = (int) startY;
canvas.clipRect(waterRect, android.graphics.Region.Op.INTERSECT);
canvas.drawColor(getResources().getColor(R.color.water));
canvas.restore();
ValueAnimator valueAnimator = ValueAnimator.ofFloat(0f, 1f);
valueAnimator.setDuration(2000);
valueAnimator.setRepeatCount(INFINITE);
valueAnimator.setRepeatMode(REVERSE);
valueAnimator.setInterpolator(new DecelerateInterpolator());
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
float progress = animation.getAnimatedFraction();
Log.d(TAG, "onAnimationUpdate " + progress);
startY = (getHeight() - 20) * (1 - progress);
startY = startY + 10;
invalidate();
}
});
valueAnimator.start();
