我相信你的code缺少像屏蔽操作：

I believe your code is missing the masking operation like:

switch (motionaction & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_POINTER_DOWN:
}

这code应能检查ACTION_POINTER_DOWN。

This code should be able to check for ACTION_POINTER_DOWN.

祝你好运和放大器;告诉我们发生了什么。

Good luck & tell us what happens.

汤米Kwee