Let me preface this by saying I am not a very good Objective C programmer. I come from a strong background in Java and enjoy Objective C becuase it's a new technology (for me) and it solves problems different from Java... well at least the API backed by Cocoa Touch solves them in a different way.
Coming from Java I will tell you this - Exception handling in Objective C is horrible! I've spent all morning dinking around trying to get a table view to display. I've been doing Objective C for 2 years now (not exclusively - but I'm not a complete newbie) so to be having problems with something this basic is pretty frustrating.
The problem really starts with me becoming more familiar with the language. As comfort levels increase I begin exploring how to solve things in slightly different ways... This is what happened today. I'm using a NavigationController to pop on a series of views (successfully until this morning).
I have this little block of boiler plate I toss around to pop a view on the NavController that looks like this:
NewViewController *vc = [[NewViewController alloc] initWithNibName:@"NewViewController" bundle:nil];
NSArray *items = [NSArray arrayWithObjects:@"Item 1", @"Item 2", @"Item 3", nil];
[vc setItems:items];
[vc setTitle:@"Items"];
[self.navigationController pushViewController:vc animated:YES];
[vc release];
[items release];
Here is the logic behind the code -
- Create a new view controller
- Create a new list to slam into the table view for the view controller and pop it in
- Set the items array into the view controller
- push the view controller into the navigation controller
- releace the memory for the view controller as it is now owned by the navigation controller
- and release the array since it is now owned by the view controller
Even now just looking at the code I just figured out what the problem is - I'm not actually creating a new instance of the items array. So by releasing it - my new view controller crashes because it's retain call got mistakenly released by someone else.
Simple problem - no big deal at all. My frustration really is that the app just crashes without any type of error at all... just a *blip* application died... Occasionally it would spit out this error:
Program received signal: “EXC_BAD_ACCESS”.
Which is not helpful at all - basically that means we accessed memory that we shouldn't have.
I agree whole heartedly that this is not a problem with Objective C - it all comes from my ignorance and lack of experience - however, it is still very frustrating.
-A
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