joec joec - 5 months ago 32
Objective-C Question

NSMutableArray addObject not working

I have declared an

NSMutableArray *categories
in my view controller .h file, and declared a property for it.

In the
parser:foundCharacters:
method of the
NSXMLParser
delegate in my .m file, I have this code:

-(void)parser:(NSXMLParser *) parser foundCharacters:(NSString *)string
{
if (elementFound)
{
element = string;
[self.categories addObject:element];
}
}


But when I hover over the
[self.categories addObject:element]
line after stepping into it in debug mode, XCode tells me the size is 0x0, 0 objects. There are 3 elements in my XML file so 3 items should be in the array.

I'm missing something really obvious and I can't figure out what.

Answer

The "0x0" part is a memory address. Specifically, "nil", which means your mutable array doesn't exist at the time this is being called. Try creating it in your -init method:

categories = [[NSMutableArray alloc] init];

Don't forget to release it in your -dealloc.

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