Question

I already have a UIButton that increment a variable each time it’s touched.
What I’d like to do now is when we stay touched on this UIButton, the variable increment it self each 0.5 seconds.

Any ideas?

Answer 1

Add an action to the event UIControlEventTouchDown where you start a timer. On UIControlEventTouchUpOutside or UIControlEventTouchUpInside you stop the timer.

[button addTarget:self action:@selector(touchedButton:) 
 forControlEvents:UIControlEventTouchDown];
[button addTarget:self action:@selector(releasedButton:) 
 forControlEvents:UIControlEventTouchUpOutside | UIControlEventTouchUpInside];

- (void)touchedButton:(id)sender {
    self.timer = [NSTimer scheduledTimerWithTimeInterval:0.5f target:self 
                  selector:@selector(timerFired:) userInfo:nil repeats:YES];
}

- (void)releasedButton:(id)sender {
    [self.timer invalidate];
}

- (void)timerFired:(NSTimer *)timer {
    counter++;
}