Re: performSelectorOnMainThread

FROM : James Bucanek
DATE : Thu Jul 20 16:43:57 2006

Eric Blanpied wrote on Thursday, July 20, 2006:

>I'm trying to use (void)performSelectorOnMainThread:(SEL)aSelector 
>withObject:(id)arg waitUntilDone:(BOOL)wait, and I don't understand 
>how to receive the argument.
>
> From the docs: "The method should not have a significant return 
>value and should take a single argument of type id, or no arguments."
>
>I can make it work when my method has no arguments, but I want to 
>pass a dictionary with some data. When I add (id)arg or (id*)arg, I 
>get an exception with "selector not recognized".
>
>What's the proper way to do this, and how would I retrieve the dict 
>once I got it? Would I cast the object as an NSDictionary?


You're probably running into the subtleties of Cocoa message naming. This one trips me up at least once a week:

    @selector(myMethod) is the selector for - (void)myMethod;
   
    @selector(myMethod:) is the selector for - (void)myMethod:(id)param;
   
Note the colon. It's important.

--
James Bucanek