How to get image coordinates in iOS app?

Question

I have to implement a signature functionality in my iPad app. I convert the signature into image and after that I want to get coordinates of that image. How could I do it plz help me.

Note: I am not talking about latitude and longitude. I am talking about pixels coordinates

Answer 1

UIViewController is a subclass of UIResponder , so you can implement the methods touchesBegan:withEvent: , touchesMoved:withEvent: , touchesEnded:withEvent: and touchesCancelled:withEvent: to detect "signing movements".

For example using the method -touchesMoved:withEvent:

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    CGPoint currentPosition = [touch locationInView:self.view];
    NSLog(@"%@", NSStringFromCGPoint(currentPosition));
}

For more info check the documentation of the UIResponder class