I am trying to perform this action on the main thread:
[curItem.mButton setBackgroundImage:newArt forState:UIControlStateNormal]; So I do this...
cWrapperObject* obj = [cWrapperObject alloc]; [obj setupParams :curItem.mButton :newArt]; [obj performSelectorOnMainThread:@selector(setImageForButton) withObject:nil waitUntilDone:YES]; I feel like this is bad, does anyone has any suggestions on how I could approach this differently?
Another option is GCD. You can invoke a block on the main queue which gets run serially when the run loop runs. blocks aren't limited to one object like performSelectorOnMainThread.
dispatch_async(dispatch_get_main_queue(), ^{ // code here }); I wrote a more comprehensive comparison of performSelectorXXX and GCD here complete with samples:
GCD, Threads, Program Flow and UI Updating
Also, here's another related SO post:
If you need to pass only one parameter, you should set up "withObject:" argument in method performSelectorOnMainThread:withObject:waitUntilDone. So your method should be declared as
-(void)setImageForButton:(id)parameter and you should invoke method on main thread with:
[obj performSelectorOnMainThread:@selector(setImageForButton:) withObject:newArt waitUntilDone:YES]; Note ':' in @selector(setImageForButton:) this means that this method will be messaged with one argument, passed in withObject:
