not getting touches from UIScrollView

Question

I have subclassed UIScrollView and implemented -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event method in it.

But Nothing happens when click or hold the scroll view!

Edit: I also need to use touchesEnded method

Can you please provide more important. Are you creating your UIScrollView through Storyboard? Make sure touch events are enabled. — David, May 03 '13 at 06:41
http://stackoverflow.com/questions/5216413/uiscrollview-getting-touch-events — Balu, May 03 '13 at 06:43

score 2 · Accepted Answer · answered May 03 '13 at 07:07

2

I think UIScrollView has two gesture recognizer. They are responsible for handling touch sequences, so they swallow the touch events.

Use scrollView delegate methods to handle drag gestures or the

touchesShouldBegin:withEvent:inContentView:

method to handle scrollview content touches and

touchesShouldCancelInContentView:

to cancel it.

As alternative you can manipulate the panGesture recognizer of the scrollView to pass the event to the next responser.

answered May 03 '13 at 07:07

Peteee24

510
4
8

That' what I was looking for! Does UIScrollView have a method which gets called when touches ends? – Burhanuddin Sunelwala May 03 '13 at 07:11
Yes, but as i told the event call gets intercepted by the gestures. Use touchesShouldBegin:withEvent:inContentView: to return YES for your special views, so they will get the touchedBegan/ended events – Peteee24 May 04 '13 at 14:08

score 1 · Answer 2 · answered May 03 '13 at 06:42

1

In your subclass of UIScrollView override the hitTest method like this:

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {

  UIView *result = nil;
  for (UIView *child in self.subviews)
    if ([child pointInside:point withEvent:event])
      if ((result = [child hitTest:point withEvent:event]) != nil)
        break;

  return result;
}

answered May 03 '13 at 06:42

Thilina Chamath Hewagama

9,039
3
32
45

Ya i had used that before. Anyways, could you explain the code? – Burhanuddin Sunelwala May 03 '13 at 06:47
[hitTest:withEvent:](http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIView_Class/UIView/UIView.html) "Returns the farthest descendant of the receiver in the view hierarchy (including itself) that contains a specified point." – Kasper Munck May 03 '13 at 07:10

score 1 · Answer 3 · answered May 03 '13 at 06:51

I think you are using scrollview as a subview.So in that case you can use gesture coz same problem i've face it.

You can do using UITapGestureRecognizer like this ...

-(void)viewDidLoad
{
   UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
   gr.delegate = self;
    [self.scrollView addGestureRecognizer:gr];
}
- (void)handleGesture:(UIGestureRecognizer *)gestureRecognizer
{
    // do here whatever you wanna ..........
}

I am not using viewcontroller – Burhanuddin Sunelwala May 03 '13 at 06:55 — Burhanuddin Sunelwala, May 03 '13 at 06:55

score 0 · Answer 4 · answered May 03 '13 at 07:36

0

Solved!

Used LongPressedGestureRecognizer. The action method keeps getting called till the user holds the view. From that i can figure out the state of the gestureRecognizer (UIGestureRecognizerStateBegan, ...Ended, ...Cancelled)

answered May 03 '13 at 07:36

Burhanuddin Sunelwala

5,318
3
25
51

not getting touches from UIScrollView

4 Answers4