Objet lancé dans un appel avec performselectoronmainthead iOS

Question

si j'utilise

[self performSelectorOnMainThread:@selector(uploadDidEnd:) withObject:foo
        waitUntilDone:YES]

dans la méthode - (VOID) UPLOADDIDENDEND: (ID) Sender

Quel objet est l'expéditeur?Dans l'appel FOO est une classe personnalisée?Comment puis-je convertir cet expéditeur dans mon objet?

J'essaie de lancer mais j'ai

'-[_NSThreadPerformInfo CountY]: unrecognized selector sent to instance 0x52bbd0'

Dans les notifications, j'utilise une distribution d'expéditeur à NSnotification et la notification a la propriété objet, mais pour NsTrhead, je n'ai pas trouvé.

merci.

Answer 1

You can think of:

[self performSelectorOnMainThread:@selector(uploadDidEnd:)
      withObject:foo
      waitUntilDone:YES]

as sort of the same as:

[self uploadDidEnd:foo];

Are you sure that's what you're trying to do?

If so: inside your uploadDidEnd: implementation, you can cast foo to whatever object type it really is like so:

- (void)uploadDidEnd:(id)sender
{
  FooClass *foo = (FooClass *)sender;
  [foo doSomething]; // or whatever
}

Answer 2

1. The argument declared a sender is the only parameter passed to your method. performSelectorOnMainThread:withObject:waitUntilDone: passes its argument after withObject to the selector to be performed, so yes, here foo will be passed to uploadDidEnd:

2. Casting is not a solution. Objective-C is a dynamic language, so even if casting eliminates compiler warnings, the actual implementation of the object wouldn't change, so it naturally would not repond to messages.