Question

The question is simple but extremely complicated: in UIResponder there are 4 methods for handling touches.

- touchesEnded:withEvent:event
– touchesBegan:withEvent:
– touchesMoved:withEvent:
– touchesCancelled:withEvent:

How do I detect if a touch stopped on the screen?

The problem is that I have to detect if something moved under a stationary touch (not cancelled or ended. It just doesn’t move) And because it doesn’t move, none of these methods gets called.

My idea was this:

I could add the touches to a NSMutableArray but then I’d have to update it for any touch move (and that’s a lot). Also this creates more problems, I need to detect which of the touches stopped and if any ended. And because I get an NSSet from UIResponder, I don’t have an organized array so… all kinds of problems.

I’m waiting for ideas.

Answer 1

i fixed it..and also found out something really cool about UITouch

what i did: in

 – touchesBegan:withEvent:
for(UITouch*touch in touches){
[touchesSet addObject:touch]; } //touchesSet is a set that i store all the touches on the screen

in

- touchesEnded:withEvent:

for(UITouch*touch in touches){
[touchesSet removeObject:touch]; }

in

– touchesCancelled:withEvent:
[touchesSet removeAllObjects];

doing this i have a NSSet of all the touches on the screen at any given time, with position and UITouchPhase