拖动图片方向的判断

/**

*拖动手势

*/

- (void)panGestureAction:(UIPanGestureRecognizer*)recognizer {

//if (recognizer.state == UIGestureRecognizerStateChanged) {

CGPointtranslation = [recognizertranslationInView:recognizer.view];

CGPointnewCenter =CGPointMake(recognizer.view.center.x+ translation.x, recognizer.view.center.y+ translation.y);

CGRectviewRect = [self.viewconvertRect:self.bigImageView.frametoView:nil];

CGFloatorigin_left_x = viewRect.origin.x;

CGFloatorigin_right_x = viewRect.size.width+ origin_left_x;

CGFloatorigin_top_y = viewRect.origin.y;

CGFloatorigin_bottom_y = viewRect.size.height+ origin_top_y;

CGPointvelocity = [recognizervelocityInView:self.view];

if(translation.y==0||fabs(translation.x/ translation.y) >5) {

if(velocity.x>0) {//向右滑动

if(origin_left_x >=0) {

return;

}

}else{//向左滑动

if(origin_right_x <=mScreenWidth) {

return;

}

}

recognizer.view.center= newCenter;

[recognizersetTranslation:CGPointZeroinView:self.view];

}

if(translation.x==0||fabs(translation.y/ translation.x) >5) {

if(velocity.y>0) {//向下滑动

if(origin_top_y >=0) {

return;

}

}else{//向上滑动

if(origin_bottom_y <=mScreenHeight) {

return;

}

}

recognizer.view.center= newCenter;

[recognizersetTranslation:CGPointZeroinView:self.view];

}

//}

}