【发布时间】:2015-04-27 01:50:23
【问题描述】:
如何仅在触发触摸事件时以固定时间间隔捕获触摸点位置。即只有在触发触摸事件后才触发时间间隔,并且在触摸事件终止时终止时间间隔。
现在我已经编写了代码来通过参考 android 开发者文档来捕获接触点。请建议如何修改代码以在规定的时间间隔内捕获触摸位置。
public boolean onTouchEvent(MotionEvent event) {
// get pointer index from the event object
int pointerIndex = event.getActionIndex();
// get pointer ID
int pointerId = event.getPointerId(pointerIndex);
// get masked (not specific to a pointer) action
int maskedAction = event.getActionMasked();
switch (maskedAction) {
case MotionEvent.ACTION_DOWN:
case MotionEvent.ACTION_POINTER_DOWN:
{
// We have a new pointer. Lets add it to the list of pointers
PointF f = new PointF();
f.x = event.getX(pointerIndex);
f.y = event.getY(pointerIndex);
// Do something
break;
}
case MotionEvent.ACTION_MOVE:
{ // a pointer was moved
for (int size = event.getPointerCount(), i = 0; i < size; i++) {
PointF f = new PointF();
f.x = event.getX(pointerIndex);
f.y = event.getY(pointerIndex);
// Do something
}
break;
}
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
case MotionEvent.ACTION_CANCEL:{
// trigger to stop the time interval
}
}
return true;
}
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