Detect single tap on UIScrollView containing 'n' UIImageViews
I am simply trying to get hold of the UIImageView that was tapped on, from the UIScrollView.
I have found 2 ways of achieving the above on the Web.
1st method : create a tap gesture on the uiimageview before adding it to scrollviewer.
This method has not worked for me. the handleSingleTap method never gets called.
I am out of ideas on what I am doing wrong/why this is not working.
UITapGestureRecognizer *singleTap =
[[UITapGestureRecognizer alloc] initWithTarget:self
action:@selector(handleSingleTap:)];
singleTap.numberOfTapsRequired = 1;
[imageView addGestureRecognizer:singleTap];
[singleTap release];
[framesSourceScrollview addSubview:imageView];
[imageView release];
- (void)handleSingleTap:(UIGestureRecognizer *)sender
{
NSLog(@"image tapped!!!");
}
2nd Method : subclass UIScrollView
@interface SingleTapScrollViewer : UIScrollView {
}
@end
@implementation SingleTapScrollViewer
- (id)initWithFrame:(CGRect)frame
{
return [super initWithFrame:frame];
}
- (void) touchesEnded: (NSSet *) touches withEvent: (UIEvent *) event
{
// If not dragging, send event to next responder
if (!self.dragging)
[self.nextResponder touchesEnded: touches withEvent:event];
else
[super touchesEnded: touches withEvent: event];
}
@end
In the ViewController
- (void) touchesEnded: (NSSet *) touches withEvent: (UIEvent *) event
{
// Process the single tap here
NSLog(@"Scroll view single tapped. touches count : %d", touches.count);
UITouch *touch = [touches anyObject];
UIImageView *imgView = (UIImageView*)touch.view;
NSLog(@"tag is %@", imgView.tag);
}
Using this method, the touchesDown responder does get called but the '[touches anyobject]' isn't the UIImageView which was tapped on.
I tried setting the 'tag' on every UIImageView I am ad开发者_StackOverflow社区ding to the scrollview with an increasing counter but I get back 0 no matter which imageview i tap on.
I am new to cocoa in general and I am not sure how to leverage this responder in any other fashion.
Any suggestions/hints would be great.
thanks in advance.
did you set the userInteractionEnabled=YES on the UIImageView. Its turned off by default.
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