touchesMoved behavior in iPhone and Simulator

Question

The function touchesMoved behaves differently in iPhone and simulator.

The repeating interval (refresh rate) of the function touchesMoved is much faster than simulator. Is there a way to deal with the difference?

Answer 1

Often people are finding this to be a problem because they are doing something intensive in the touchesMoved handler and when events arrive very frequently, it makes the interface appear to lag.

A relatively simple way to deal with this is: First of all, in the touchesMoved handler, store the touch position in a variable that represents the position of whatever is tracking the finger.

Return from the touchesMoved handler immediately. Create an NSTimer object and set your view controller as a delegate of it and have that do whatever re-drawing/view moving behaviour used to be in your touchesMoved handler. Thus, you get a near constant movement regardless of the time between touchesMoved events.

If you're really advanced you can use a custom NSRunLoop instead of using a timer, but that's more than I can explain here :) The general idea is: don't be doing everything in the touch event handlers.