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iOS Touch Events

Hayden Pennington
Hayden Pennington
6,154 Points
Posted by Hayden Pennington
Hayden Pennington
6,154 Points

setNeedsDispay

Is the call to 'setNeedsDisplay()' actually beneficial in this code? If so, can someone please explain why?

I removed the call to 'setNeedsDisplay' from the touchesBegan method. Now, drawRect is only called once. However, the app still functions as expected.

I can understand wanting drawRect to be called if we wanted to change attributes of the crosshair, but in this case we're only changing the position.

Hopefully someone can shine some light on this for me. Thanks!

  • Hayden