Alex Rivera | Logout

Way to make a UIButton continuously fire during a press-and-hold situation?

Asked 2009-05-24T04:58:04.243
19

You know how Mario just keeps running to the right when you press and hold the right-button on the D-Pad? In the same manner, I want my UIButton to continuously fire its action for the duration that it is held down. Is this possible for a UIButton? If not, is this possible to do with a UIImageView by overriding a touch handling method in a certain way? Actually, before trying to do get this done with UIButton I had some UIImageViews (Arranged to function as a D-Pad) that were checked by touch handling methods but things started to get messy so I thought this could be done easier with UIButton and thus switched over. Anybody who knows how to get recognition of a continuous, stationary (not-moved) down-touch, please share.

iphone cocoa-touch uibutton multi-touch
Edit
Report

1 Answer

32

Don't use a button, use multi-touch and NSTimer:

Make a view-local NSTimer object inside your interface, then use it to start/cancel the timer

-(void)movePlayer:(id)sender {
   <Code to move player>
}

-(void)touchesBegan:(NSSet*)touches  withEvent:(UIEvent*)event {
    timer = [NSTimer scheduledTimerWithTimeInterval:0.3 target:self selector:@selector(movePlayer:) userInfo:nil repeats:YES];
}

-(void)touchesEnded:(NSSet*)touches  withEvent:(UIEvent*)event {
   if (timer != nil) 
      [timer invalidate];
      timer = nil;
}

-(void)touchesMoved:(NSSet*)touches  withEvent:(UIEvent*)event {
    if (timer != nil) {
       [timer invalidate];
       timer = nil;
    }
}

This way, you can repeat the event at a predefined interval, and not have to rely on a button, and get the repeat behaviour you're looking for. Note the touchesMoved trigger - if they move their finger, this cancels the timer, and the player stops moving.

answered 2009-05-24T05:08:16.430

Your Answer