Question

I want to add a gesture recognizer to my button so that I can run code if the user swiped past the buttons frame. I also want this code to be different if the swipe was up, right, left, or down the button.

-(void)viewDidLoad
{
    [super viewDidLoad];
    UIButton *button=[UIButton buttonWithType:UIButtonTypeRoundedRect];
    button.frame=CGRectMake(0, 0, 100, 100);
    [self.view addSubview:button];
    UIGestureRecognizer *swipe=[[UIGestureRecognizer alloc]initWithTarget:button action:@selector(detectSwipe)];
    [button addGestureRecognizer:swipe];
}

so, did I do the initWithTarget:action: thing correct? And now that I do this how do i Implement the detectSwipe method?

here is my idea on how to implement detectSwipe

          -(IBAction)detectSwipe:(UIButton *)sender
        {
      /* I dont know how to put this in code but i would need something like, 
if (the swipe direction is forward and the swipe is > sender.frame ){ 
[self ForwardSwipeMethod];
    } else if //same thing for right
    else if //same thing for left
    else if //same thing for down

        }

Answer 1

You probably want to be using a UISwipeGestureRecognizer. UIGestureRecognizer usually shouldnt be used unless you are subclassing it. Your code should look similar to the following.

UISwipeGestureRecognizer *swipe=[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(detectSwipe)];
swipe.direction = UISwipeGestureRecognizerDirectionRight;
[button addGestureRecognizer:swipe];