I have an object of image type which I am moving using UIPanGestureRecognizer, and I need to stop recognizing the UIPanGestureRecognizer when the object reaches a certain frame.
UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(move:)];
[panRecognizer setMinimumNumberOfTouches:1];
[panRecognizer setMaximumNumberOfTouches:1];
[panRecognizer setDelegate:self];
[templatePhotoPlaceholderView addGestureRecognizer:panRecognizer];
-(void)move:(UIPanGestureRecognizer *)gestureRecognizer
{
CGPoint translatedPoint = [gestureRecognizer translationInView:templatePhotoPlaceholderView];
if([gestureRecognizer state] == UIGestureRecognizerStateBegan) {
_firstX = [imageview center].x;
_firstY = [imageview center].y;
}
translatedPoint = CGPointMake(_firstX+translatedPoint.x, _firstY+translatedPoint.y);
//NSLog(@" Move center point :%@", NSStringFromCGPoint(translatedPoint));
[imageview setCenter:translatedPoint];
}
How may I do this ?
UIGestureRecognizers have an enabled property. Documentation:
Disables a gesture recognizers so it does not receive touches. The default value is YES. If you change this property to NO while a gesture recognizer is currently recognizing a gesture, the gesture recognizer transitions to a cancelled state.
EDIT:
Just set the enabled property to NO.
gestureRecognizer.enabled = NO;
When you need to stop your UIPanGestureRecognizer from recognizing gesture, you just put this code line (as jbat100 said) in -(void)move:(UIPanGestureRecognizer *)gestureRecognizer
:
gestureRecognizer.enabled = NO;
after this line your gestureRecognizer state set as "UIGestureRecognizerStateCancelled"
then just add couple lines to your -(void)move:(UIPanGestureRecognizer *)gestureRecognizer
function:
if ([gestureRecognizer state] == UIGestureRecognizerStateCancelled) {
gestureRecognizer.enabled = YES;
}
and you'll be able to work with your gesture recognizer
EDIT:
Here's code snippet:
- (void)move:(UIPanGestureRecognizer *)gestureRecognizer {
BOOL cancelPanGesture = YES;
if (cancelPanGesture) {
/*
After this line gesture recognizer will be disabled, state will be UIGestureRecognizerStateCancelled
and this method (move:) will fire one more time.
*/
gestureRecognizer.enabled = NO;
}
if (gestureRecognizer.state == UIGestureRecognizerStateCancelled) {
gestureRecognizer.enabled = YES;
}
}
Set the pangesture.delegate=self, and implement delegate method
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
//return NO when you reach the frame
}
来源:https://stackoverflow.com/questions/8078780/how-to-stop-uipangesturerecognizer-when-object-moved-to-certain-frame