Re: Loops in Objective C?

FROM : Nathan Kinsinger
DATE : Mon May 26 21:31:15 2008

On May 26, 2008, at 1:20 PM, Nathan wrote:

> so I have a .m file, here's the contents.
>
> #import "RotationHandler.h"
>
> @implementation RotationHandler
> int z=1;
> float rot;
> - (IBAction)buttonRelease:(id)sender {
>     do
>     {
>         rot=rot-0.5;
>         [sliderRotation setFrameCenterRotation: rot];
>         [printRotation setFloatValue: rot];
>     }
>     while(z=1);
> }
>
> @end
>
> I won't bother showing you the other files in the project I know 
> they're all in order. So I want the object receiving sliderRotation 
> to rotate, in the above code I want it to rotate forever. If I 
> remove the loop, each time I press the button it rotates -.5 
> degrees. But with the loop in there, I get the horrible spinning 
> beachball of eternity when I press the button and the object that is 
> supposed to rotate never moves. Do I have to use some special 
> Objective C loop?


The problem here is that looping forever will not let the rest of the 
program run. So the drawing code will never get called. Look into 
NSTimer to run a method that will do your rotation on some interval.

--Nathan