UITapGestureRecognizer breaks UITableView didSelec

Question

I have written my own function to scroll text fields up when the keyboard shows up. In order to dismiss the keyboard by tapping away from the text field, I've created a UITapGestureRecognizer that takes care of resigning first responder on the text field when tapping away.

Now I've also created an autocomplete for the textfield that creates a UITableView just below the text field and populates it with items as the user enters text.

However, when selecting one of the entries in the auto completed table, didSelectRowAtIndexPath does not get called. Instead, it seems that the tap gesture recognizer is getting called and just resigns first responder.

I'm guessing there's some way to tell the tap gesture recognizer to keep passing the tap message on down to the UITableView, but I can't figure out what it is. Any help would be very appreciated.

Answer 1

My case was different including a uisearchbar and uitableview on self.view. I wanted to dismiss uisearchbar keyboard by touching on the view.

var tapGestureRecognizer:UITapGestureRecognizer?

override func viewWillAppear(animated: Bool) {
    tapGestureRecognizer = UITapGestureRecognizer(target: self, action:Selector("handleTap:"))
}

On UISearchBar Delegate Methods:

func searchBarShouldBeginEditing(searchBar: UISearchBar) -> Bool {
    view.addGestureRecognizer(tapGestureRecognizer!)
    return true
}
func searchBarShouldEndEditing(searchBar: UISearchBar) -> Bool {
    view.removeGestureRecognizer(tapGestureRecognizer!)
    return true
}

When user touches on self.view:

func handleTap(recognizer: UITapGestureRecognizer) {
    sampleSearchBar.endEditing(true)
    sampleSearchBar.resignFirstResponder()
}

Answer 2

ISSUE: In my case, the issue was that I originally placed a button in each collectionView cell and set the constraints to fill the cell, so that when the cell was clicked it would click the button, however the buttons function was empty so nothing was appearing to be happening.

FIX: I fixed this by removing the button from the collection view cell.

Answer 3

Set cancelsTouchesInView of your recognizer to false. Otherwise, it "consumes" the touch for itself, and does not pass it on to the table view. That's why the selection event never happens.

for example in swift

let tapOnScreen: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: "CheckTheTime")
tapOnScreen.cancelsTouchesInView = false
view.addGestureRecognizer(tapOnScreen)

Answer 4

And for Swift (based on answer from @Jason):

class MyAwesomeClass: UIViewController, UIGestureRecognizerDelegate

private var tap: UITapGestureRecognizer!

override func viewDidLoad() {
   super.viewDidLoad()

   self.tap = UITapGestureRecognizer(target: self, action: "viewTapped:")
   self.tap.delegate = self
   self.view.addGestureRecognizer(self.tap)
}

// UIGestureRecognizerDelegate method
func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldReceiveTouch touch: UITouch) -> Bool {
    if touch.view?.isDescendantOfView(self.tableView) == true {
        return false
    }
    return true
}

Answer 5

Here is my solution, which ties the recognizer's shouldReceiveTouch directly to whether the keyboard is showing.

In your tap gesture recognizer delegate:

#pragma mark - UIGestureRecognizerDelegate

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
    if ([PFXKeyboardStateListener sharedInstance].visible) {
        return YES;
    }

    return NO;
}

And the PFXKeyboardStateListener.h:

@interface PFXKeyboardStateListener : NSObject
{
    BOOL _isVisible;
}

+ (PFXKeyboardStateListener *)sharedInstance;

@property (nonatomic, readonly, getter=isVisible) BOOL visible;

@end

And the PFXKeyboardStateListener.m:

static PFXKeyboardStateListener *sharedInstance;

@implementation PFXKeyboardStateListener

+ (PFXKeyboardStateListener *)sharedInstance
{
    return sharedInstance;
}

+ (void)load
{
    @autoreleasepool {
        sharedInstance = [[self alloc] init];
    }
}

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

- (BOOL)isVisible
{
    return _isVisible;
}

- (void)didShow
{
    _isVisible = YES;
}

- (void)didHide
{
    _isVisible = NO;
}

- (id)init
{
    if ((self = [super init])) {
        NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
        [center addObserver:self selector:@selector(didShow) name:UIKeyboardDidShowNotification object:nil];
        [center addObserver:self selector:@selector(didHide) name:UIKeyboardWillHideNotification object:nil];
    }
    return self;
}

@end

You may want to update the singleton pattern of the keyboard listener, I haven't gotten to it yet. Hope this works for everyone else as well as it works for me. ^^

Answer 6

Ok, finally found it after some searching through gesture recognizer docs.

The solution was to implement UIGestureRecognizerDelegate and add the following:

////////////////////////////////////////////////////////////
// UIGestureRecognizerDelegate methods

#pragma mark UIGestureRecognizerDelegate methods

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
    if ([touch.view isDescendantOfView:autocompleteTableView]) {

        // Don't let selections of auto-complete entries fire the 
        // gesture recognizer
        return NO;
    }

    return YES;
}

That took care of it. Hopefully this will help others as well.