touchesBegan with delay

问题

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.

回答1:

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.

回答2:

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];
    }
}

来源：https://stackoverflow.com/questions/31828857/touchesbegan-with-delay