Move object while user holding touch

Question

I want to create simple app (clone of Road Fighter actually http://youtu.be/CDMcY3wLd1Q) where: rectangle UIView (car) moves left, if user press left side of screen and it moves right if user press right side.

I already figured out how to recognise touches (two ways: with "UILongPressGestureRecognizer" and with "touchesBegan:" function) but i don't understand how to create animation.

Pseudocode should looks like this (or maybe i'm wrong):

if user touch
    if touch.coordinate.x>160 then
        while holding
            UIView.coordinate.x += 0.01;
    if touch.coordinate.x<160 then
        while holding
            UIView.coordinate.x -= 0.01;

Answer 1

There's another function called -(void)touchesEnded so when touchbegan, you keep move the car to one direction and stop moving while touchesended was called. Simple solution is using a flag like bool carismovingleft call the loop moving function in touchbegin:

- (void)touchesBegan... {
    //mark the flag
    self.carismovingleft = true;
    //start moving the car  
    [self movingcar];
}

- (void)movingcar {
    if (self.carismovingleft) {
        //move the car subview to left a little bit
        .......
        //now we keep moving a little bit till someone  stop it
        //call moving again after a delay 
        //otherwise the car will move all the way in one frame
        [self performSelector: @selector(movingcar) withObject:nil afterDelay:1];
    }
}

- (void)touchesEnded... {
    //stop flag
    self.carismovingleft = false;
}

It's just a basic concept of how to implement it, you need coding by yourself.