Re: Getting the right objects in an Array

FROM : Shawn Erickson
DATE : Mon Nov 05 19:37:59 2007

On 11/5/07, Marcel Borsten <<email_removed>> wrote:

> I'm using the following code to fill a NSMutableArray with strings
> from the NSDictionary object. The for loop gets the instances of the
> keys 'name' and puts the string in the mutable array object
> 'firstNames'. In my program it uses the firstNames-array to fill a
> NSPopupButton with the Array of NSStrings. When that happens the
> program exits with a "EXC_BAD_ACCESS"-error.


When what happens? What it the stack trace at the time of the crash?

> It looks to me that the
> objects in the returned mutable array are not NSString objects. When I
> debug, Xcode shows my NSString-value as 'invalid'.


Consider using NSLog to help trace what is taking place however the
debugger is usually the best way. Are you sure you are using a debug
build of you application and stopping at a point in time that ensures
the vars you are interested in are valid (in scope).

For example try using the following code...

...
    NSArray *myArray = [dict objectForKey: @"List"];
    NSLog(@"myArray=%@", myArray);

    firstNames = [NSMutableArray array];

    int i, myNameList = [myArray count];
    for ( i = 0; i < myNameList; i++ ) {
        NSDictionary *nameEntry = [myArray objectAtIndex: i];
        NSLog(@"nameEntry=%@", nameEntry);

        NSString *name = [nameEntry valueForKey:@"name"];
        NSLog(@"name=%@", name);

        [firstNames addObject: name];
    }
...

If the above logs what you expect then your problem is someplace
else... As a guess I would say you aren't managing the life of
firstNames correctly and it is disappearing before you get a chance to
update your view object with the data.

You don't list how you populate the NSPopupButton.

-Shawn