Confusion around NSMutableArray and NSArray

Question

I have the following code:

NSLog(@"items: %d", [items count]);
NSLog(@"allObjects: %d", [self.allObjects count]);

[self.allObjects addObjectsFromArray:items];

NSLog(@"allObjects: %d", [self.allObjects count]);

Which produces the following output:

items: 7
allObjects: 0
allObjects: 0

items is a NSArray

allObjects is a NSMutableArray.

I'm confused as to why the objects in items are not being added to allObjects. I expect it's something simple, but there is a hole in my understanding here.

can you post the code where you instantiate allObjects?

Nick Moore
– Nick Moore

2010-03-23 14:54:59 +00:00
Commented Mar 23, 2010 at 14:54 — Nick Moore
– Nick Moore, Commented Mar 23, 2010 at 14:54

kennytm · Accepted Answer · 2010-03-23 14:54:09Z

5

Let me guess. self.allObjects is nil. Sending messages to nil is a no-op.

answered Mar 23, 2010 at 14:54

kennytm

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1 Comment

Codebeef Over a year ago

facepalm Might have to call it a day. Ugh.

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