PanGestureRecognizer fails to fire on UIScrollView when SWRevealController is being used

Question

I am using the SWRevealViewController project by John Lluch for my application and I have run into one minor issue that I can't seem to get straight.

I am using the SWRevealViewController to access my apps options menu from anywhere in my app just by swiping to the right and the main view slides to reveal the menu behind it.

This is handled by a swipe gesture recognizer that is added to the main view. To improve UX, I create a button to cover the main view when it gets swiped out of the way so all the user has to do to close the menu is tap the small part of the view that is showing or grab the view and pull it back.

It works great except on one of my views in which the majority of the view is a UIScrollView. To get it to work I have to add the gesture recognizer to the UIScrollView as well as the super view. But for some reason, once the view is swiped out of the way, the swipe gesture recognizer stops responding. But this only happen on the view where the majority of the screen is a scroll view thus, what the user grabs to pull the screen back is the scroll view.

Hopefully that was understandable. Any light that you guys can shine on this will be very helpful.

-(void)viewDidAppear:(BOOL)animated {
    // so the user can tap the button to show the menu
    [menuButton addTarget:self.revealViewController action:@selector(revealToggle:) forControlEvents:UIControlEventTouchUpInside];

    // so the user can swipe to show the menu
    [self.view addGestureRecognizer:self.revealViewController.panGestureRecognizer];

    // so the user can swipe the scrollview to show the menu
    [mainScrollView addGestureRecognizer:self.revealViewController.panGestureRecognizer];

    self.revealViewController.delegate = self;
}

- (void)revealController:(SWRevealViewController *)revealController willMoveToPosition:(FrontViewPosition)position {
    if (position == FrontViewPositionRight) {
        //create the button so the use can tap to close the menu
        returnButton = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];

        [returnButton addTarget:self.revealViewController action:@selector(revealToggle:) forControlEvents:UIControlEventTouchUpInside];

        [self.view addSubview:returnButton];
    } else {
        [returnButton removeFromSuperview];
        returnButton = nil;
    }
}

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score 0 · Answer 1 · edited May 23 '17 at 12:14

So I just discovered that this issue has already been addressed within the SWRevealViewController Project. This post pointed me in the right direction. They have added a tap gesture recognizer that has the behaviour I was creating with the dynamically created button.

Adding

[self.view addGestureRecognizer:self.revealViewController.tapGestureRecognizer];

removes the need for the button, thus allowing the view to respond to both recognizers.

PanGestureRecognizer fails to fire on UIScrollView when SWRevealController is being used

1 Answers1