I've just run into blocks and I think they are just what I'm looking for, except for one thing: is it possible to call a method [self methodName] from within a block?
This is what I'm trying to do:
-(void)someFunction{
Fader* fader = [[Fader alloc]init];
void (^tempFunction)(void) = ^ {
[self changeWindow:game];
//changeWindow function is located in superclass
};
[fader setFunction:tempFunction];
}
I've been searching for a couple of days and I can't find any evidence that this is possible.
Is this at all possible, or am I trying to use blocks for something they aren't meant for?
The reason I'm using blocks is that I've created a Fader class, and I want to store a block for it to execute when it finishes fading out.
Thank you
EDIT: Okay, I added in the suggestion, but I'm still getting an EXC_BAD_ACCESS error...
-(void)someFunction{
Fader* fader = [[Fader alloc]init];
__block MyScreen* me = self;
void (^tempFunction)(void) = ^ {
[me changeWindow:game];
//changeWindow function is located in superclass
};
[fader setFunction:tempFunction];
[fader release];
}
Maybe I'm not allowed to give fader the function...?
Yes, you can do this.
Note, however, that the block will retain self
. If you end up storing this block in an ivar, you could easily create a retain cycle, which means neither would ever get deallocated.
To get around this, you can do:
- (void) someMethodWithAParameter:(id)aParameter {
__block MySelfType *blocksafeSelf = self;
void (^tempFunction)(void) = ^ {
[blocksafeSelf changeWindow:game];
};
[self doSomethingWithBlock:tempFunction];
}
The __block
keyword means (among other things) that the referenced object will not be retained.