touchesBegan with delay

Question

I have a subclass of UIView, and added the touchesBegan and touchesEnd methods...

In touchesBegan, I set the backgroundColor from white to green by using self.backgroundColor = [UIColor greenColor] ... in the touchesEnd I reset the color to white.

It works but very slowly. By tapping the view, it takes 0.5 - 1.0 sec until I see the green color.

Selecting a cell in a UITableView it's much faster.

hm, might be due to an implicit animation when setting properties like backGroudn color. Can you check if the touch is late or only the change of color? — Volker, Aug 05 '15 at 09:46
This UIView of yours happens to be inside of a UITableView or a UIScrollView ? — The dude, Aug 05 '15 at 09:48
@Volker Nice thinking, but `UIKit` disables implicit animations of underlying `CALayer`s ([see this great answer here](http://stackoverflow.com/questions/4749343/when-exactly-do-implicit-animations-take-place-in-ios)), so I guess this is not the problem. I would look for `delaysContentTouches` of a superview or something similar. — Alladinian, Aug 05 '15 at 09:51
I know this has already an accepted answer, but I suggest you try this out: UITableViews delay content touches by default. It has a property called delaysContentTouches, you should set it to NO. https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIScrollView_Class/#//apple_ref/occ/instp/UIScrollView/delaysContentTouches — The dude, Aug 05 '15 at 13:02

score 4 · Accepted Answer · answered Aug 05 '15 at 10:04

4

Try this:

self.view.userInteractionEnabled = YES;
    UILongPressGestureRecognizer *recognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(doCallMethod:)];
    recognizer.delegate = self;
    recognizer.minimumPressDuration = 0.0;
    [self.view addGestureRecognizer:recognizer];

- (void)doCallMethod:(UILongPressGestureRecognizer*)sender {
    if(sender.state == UIGestureRecognizerStateBegan){
        NSLog(@"Begin");
        self.view.backgroundColor = [UIColor greenColor];
    }else if (sender.state == UIGestureRecognizerStateEnded){
        NSLog(@"End");
        self.view.backgroundColor = [UIColor whiteColor];
    }
}

Note: It will work more faster.

answered Aug 05 '15 at 10:04

Mayur Prajapati

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ok this works but if i putmy new View in a UITableViewCell ... i'cant swipe the cell to see the remove button :-( – Maurice Raguse Aug 05 '15 at 15:34
Works, but if the view is inside a superView of kind UIScrollView... the ScrollView can't scroll by beginning the scroll inside the view with minimumDressDuration = 0.0 ... so you have to adjust this value to e.g. 0.1 ... and the UIScrollView is able to scroll – Maurice Raguse Aug 06 '15 at 09:44
1

why touchesBegan will have delay? anyway to speed up? – TomSawyer Nov 16 '15 at 03:09

score 2 · Answer 2 · answered Aug 05 '15 at 09:58

You should use a gesture recognizer as TheBurgerShot suggested but I recommend you an UILongPressGestureRecognizer. Something like:

UILongPressGestureRecognizer *gesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(changeColor:)];
gesture.minimumPressDuration = 0.f;
[self.yourView addGestureRecognizer:gesture];

in your viewDidLoad. And:

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

    if (gestureRecognizer.state == UIGestureRecognizerStateBegan){
        self.yourView.backgroundColor = [UIColor greenColor];
    }
    else if (gestureRecognizer.state == UIGestureRecognizerStateEnded){
        self.yourView.backgroundColor = [UIColor whiteColor];
    }
}

do you know why touchesbegan has some delay? use gesture can solve the trouble but can't have every attributes like touchesbegan like multiple touch. — TomSawyer, Nov 16 '15 at 07:25

touchesBegan with delay

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