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Gesture recognizer and button actions

开发者 https://www.devze.com 2023-02-07 09:13 出处:网络
I have a view hierarchy that looks something like this: UIView (A) UIView > UIImageView UIView > UIView (B)

I have a view hierarchy that looks something like this:

UIView (A)
UIView > UIImageView
UIView > UIView (B)
UIView > UIView (B) > Rounded Rect Button
UIView > UIView (B) > UIImageView
UIView > UIView (B) > UILabel

I've attached gesture recognizer(s) to my UIView (B). The problem that i'm facing is that i don't get any actions for the Rounded Rect Button which is inside the UIView (B). The singleTap gesture recognizer captures/overrides the button's Touch Up Inside event.

How can i make it work? I thought that the responder chain hierarchy will make sure that the button touch event will be given preference, and it WILL get triggered! What am i missing?

Here's some related code:

#pragma mark -
#pragma mark View lifecycle (Gesture recognizer setup)

- (void)viewDidLoad {
    [super viewDidLoad];

    // double tap gesture recognizer
    UITapGestureRecognizer *dtapGestureRecognize = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doubleTapGestureRecognizer:)];
    dtapGestureRecognize.delegate = self;
    dtapGestureRecognize.numberOfTapsRequired = 2;
    [self.viewB addGestureRecognizer:dtapGestureRecognize];

    // single tap gesture recognizer
    UITapGestureRecognizer *tapGestureRecognize = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(singleTapGestureRecognizer:)];
    tapGestureRecognize.delegate = self;
    tapGestureRecognize.numberOfTapsRequired = 1;
    [tapGestureRecognize requireGestureRecognizerToFail:dtapGestureRecognize];
    [self.viewB addGestureRecognizer:tapGestureRecognize];

    // add gesture recodgnizer to the grid view to start the edit mode
    UILongPressGestureRecognizer *pahGestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressGestureRecognizerStateChanged:)];
    pahGestureRecognizer.delegate开发者_开发百科 = self;
    pahGestureRecognizer.minimumPressDuration = 0.5;
    [self.viewB addGestureRecognizer:pahGestureRecognizer];

    [dtapGestureRecognize release];
    [tapGestureRecognize release];
    [pahGestureRecognizer release];
}

#pragma mark -
#pragma mark Button actions

- (IBAction)buttonTouchUpInside:(id)sender {
    NSLog(@"%s, %@", __FUNCTION__, sender);
}

#pragma mark -
#pragma mark Gesture recognizer actions


- (void)singleTapGestureRecognizer:(UIGestureRecognizer *)gestureRecognizer {
    NSLog(@"%s", __FUNCTION__);
}

- (void)doubleTapGestureRecognizer:(UIGestureRecognizer *)gestureRecognizer {
    NSLog(@"%s", __FUNCTION__);
}

- (void)longPressGestureRecognizerStateChanged:(UIGestureRecognizer *)gestureRecognizer {

    switch (gestureRecognizer.state) {

        case UIGestureRecognizerStateEnded: {
            NSLog(@"%s", __FUNCTION__);

            break;
        }
        default:
            break;
    }
}


In the "shouldReceiveTouch" method you should add a condition that will return NO if the touch is in the button.

This is from apple SimpleGestureRecognizers example.

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {

    // Disallow recognition of tap gestures in the segmented control.
    if ((touch.view == yourButton)) {//change it to your condition
        return NO;
    }
    return YES;
}

hope it will help

Edit

As Daniel noted you must conform to UIGestureRecognizerDelegate for it to work.

shani


I also had the same problem , then i tried with

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch{

    if ([touch.view isKindOfClass:[UIButton class]]) {      //change it to your condition
        return NO;
    }
    return YES;
}

It is working now perfectly.........


Generally speaking, we use below delegate method to avoid the touch in all kinds of UIControls:

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
    if (([touch.view isKindOfClass:[UIControl class]])) {
         return NO;
    }
    return YES;
}

Note: DO NOT do this check (check the recognizer.view class type) the gestureRecognizerShouldBegin, it won't work.


Here is a Swift 3.0 version:

extension UIViewController: UIGestureRecognizerDelegate {

public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
    if touch.view is UIButton {
        return false
    }
    return true
}

Don't forget to:

Make your tapper object delegate to self (e.g: tapper.delegate = self)


The best solution is to my mind using code snippet below:

-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
    CGPoint touchLocation = [touch locationInView:self.view];
    return !CGRectContainsPoint(self.menuButton.frame, touchLocation);
}


Here is a Swift version:

func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldReceiveTouch touch: UITouch) -> Bool {
    if (touch.view!.isKindOfClass(UIButton)) {
        return false
    }
    return true
}

Don't forget to:

  1. Make you class conform to UIGestureRecognizerDelegate
  2. Make your tapper object delegate to self (e.g: tapper.delegate = self)


for Swift 5 inside the delegate you can just add:

return (touch.view is UIButton) ? false : true


Swift version of Vivienne answer:

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
    let location = touch.location(in: view)
    return !someView.frame.contains(location)
}


My case was the following :

UIView (with tap gesture)
├-> UIView (named "textFieldView")
    ├-> UIControl
    ├-> UITextField
    ├-> UIView (over the textField, with a tap gesture)

╭──────────────────────────────╮
│ ╭──────────────────────────╮ │
│ │ ╭──╮  ┌╴╶╴╶╴╶╴╶╴╶╴╶╴╶╴╶┐ │ │
│ │ ╰──╯  └╴╶╴╶╴╶╴╶╴╶╴╶╴╶╴╶┘ │ │
│ ╰──────────────────────────╯ │
└──────────────────────────────┘

The tapGesture on the upper UIView was causing a conflict with the UIControl target. The target was called if the target was setup with touchDown (but not called for touchUpInside) or if I was changing the inheritance from UIControl to UIButton while keeping the target setup on event touchUpInside.

What I do to solve that is : upper view is setup as delegate of its tap gesture. Function func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool is implemented (in upper UIView) like that :

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
    let touchLocationRelatedToTextFieldView = touch.location(in: textFieldView)
    return textFieldView.frame.contains(touchLocationRelatedToTextFieldView) == false
}

With that delegate function implemented I'm now able to keep my UIControl and the target setup on touchUpInside! :)

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