I have a method that is moving a UIImageView called shootImg across the screen:

-(IBAction)shoot{
if (appDelegate.shootInt > 0) {
    if (direction == 1) {
            shootImg.center = CGPointMake(shootImg.center.x+1, shootImg.center.y);
            appDelegate.shootInt = appDelegate.shootInt - 1;
            shootLabel.text = [NSString stringWithFormat:@"%d", appDelegate.shootInt];
                }

This does seem to work. But it only moves shootImage 1 pixel. What I want to do is make it repeatedly move 1 pixel. I tried a while loop but that didn't seem to work. I'm not using cocos2d or anything like that and if you need to see more code just ask.

Thanks :)