手势平滑拖动控件

- (void) doHandlePanAction:(UIPanGestureRecognizer *)paramSender {
CGPoint point = [paramSender translationInView:self.view];

CGPoint newCenter = CGPointMake(paramSender.view.center.x + point.x, paramSender.view.center.y + point.y);//限制屏幕范围：

newCenter.y = MAX(paramSender.view.height/2, newCenter.y);

newCenter.y = MIN(self.view.height - paramSender.view.heigh /2 - 49, newCenter.y);

newCenter.x = MAX(paramSender.view.width/2, newCenter.x);

newCenter.x = MIN(self.view.width - paramSender.view.width/2, newCenter.x);

if(paramSender.state == UIGestureRecognizerStateChanged) {

paramSender.view.center = newCenter;

[paramSender setTranslation:CGPointMake(0, 0) inView:self.view];

}

if (paramSender.state == UIGestureRecognizerStateEnded) {

CGPoint tempPoint = newCenter;

if (newCenter.x < screenW/2.0) {

newCenter.x = paramSender.view.width/2;

} else {

newCenter.x = self.view.width- paramSender.view.width/2;

}

float seconds = ((fabs(tempPoint.x - newCenter.x))/screenW/2.0);

[UIView animateWithDuration:seconds animations:^{

paramSender.view.center = newCenter;

}];
}
}