How to know which view the user touches on screen

Question

If there is a uiscrollview and and multiple sub view on the uiscrollview. how to know where the user touches i.e on specific view or scrollview(blank space)

score 5 · Answer 1 · edited May 23 '17 at 12:05

5

Use this approach:

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
        UITouch *touch = [touches anyObject];
        NSLog(@"View touched: %@", touch.view);
}

This method is called every time your finger touches the screen, and the touch knows which view it touched.

Edit: It won't work on a UIScrollView because the scroll view gets the touch itself, check this:

touchesBegan method not called when scrolling in UIScrollView

How to enable touch began in UIScrollView?

edited May 23 '17 at 12:05

Community

1
1

answered Oct 22 '13 at 09:20

Antonio MG

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but it is not getting called when we use scrollview and add sub view to scroll view – pradeep Oct 22 '13 at 09:23
Is there any option to detect the touches on scrollview – pradeep Oct 22 '13 at 09:32
That method should be triggered whatever it is on the screen. – Antonio MG Oct 22 '13 at 09:39
You have to implement this method on the superView, for example self.view – Magyar Miklós Oct 22 '13 at 09:43
It is not getting called if the base view is scroll view – pradeep Oct 22 '13 at 09:44
USe this: http://stackoverflow.com/questions/3386840/how-to-enable-touch-began-in-uiscrollview or this http://stackoverflow.com/questions/5971819/touchesbegan-method-not-called-when-scrolling-in-uiscrollview – Antonio MG Oct 22 '13 at 09:45
1

I added a solution to you – Magyar Miklós Oct 22 '13 at 09:53

score 3 · Accepted Answer · answered Oct 22 '13 at 09:50

You have 2 possibilities for detect the touch with - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event; in a scrollView:

first, implement this method in your viewController, and add the scrollview on this viewController.

second, which I recommend: make a custom class which is inherited from UIScrollView like this: .h:

@interface CustomScrollView : UIScrollView 

@end

.m:

#import "CustomScrollView.h"


@implementation CustomScrollView

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    [self.nextResponder touchesBegan:touches withEvent:event];
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
    if(!self.dragging){
        [self.nextResponder touchesMoved:touches withEvent:event];
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
    [self.nextResponder touchesEnded:touches withEvent:event];
}

@end

in your vc make:

...

CustomScrollView* customScrollView = [[CustomScrollView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];

...

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
        UITouch *touch = [touches anyObject];
        NSLog(@"View touched: %@", touch.view);
}

How to know which view the user touches on screen

2 Answers2