Question

Here’s my code:

test.h

@interface testAppDelegate : NSObject <NSApplicationDelegate> {
    NSWindow *window;
    IBOutlet NSTableView *test;
    NSMutableArray *internalArray;
}

@property (assign) IBOutlet NSWindow *window;
@property (nonatomic, retain) NSTableView *test;
-(id) initWithArray: (NSArray*) objects;
-(int)numberOfRowsInTableView:(NSTableView *)aTableView;
-(id)tableView:(NSTableView *)aTableView objectValueForTableColumn:(NSTableColumn     *)aTableColumn row:(int)rowIndex;
-(void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(int)rowIndex;

test.m (top pieces missing for simplicity’s sake)

@synthesize window;
@synthesize test;

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
    PSClient *client = [PSClient applicationClient];
    NSURL *url = [NSURL URLWithString:@"http://www.apple.com/main/rss/hotnews/hotnews.rss"];
    PSFeed *feed = [client addFeedWithURL:url];
    internalArray = [NSMutableArray array];

    // Retrieve the entries as an unsorted enumerator
    NSEnumerator *entries = [feed entryEnumeratorSortedBy: nil];
    PSEntry *entry;
    // Go through each entry and print out the title, authors, and content
    while (entry = [entries nextObject]) {
        [internalArray addObject:entry.title];
        //NSLog(@"Entry Title:%@", entry.title);
        //NSLog(@"Entry Authors:%@", entry.authorsForDisplay);
        [test reloadData];
        //NSLog(@"Entry Content:%@", entry.content.plainTextString);
    }
}

-(int)numberOfRowsInTableView:(NSTableView *)aTableView{
    NSLog(@"%@", [internalArray count]);
    return [internalArray count];
}

-(id)tableView:(NSTableView *)aTableView objectValueForTableColumn:(NSTableColumn *)aTableColumn row:(int)rowIndex
{
    NSString *string = [internalArray objectAtIndex:rowIndex];
    NSLog(@"%@", string);
    // when I debug, I get same pointers with invalid data
    // each object has "name" message
    // this following line gives invalid pointer and
    // it crashes
    return string;
}

-(void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(int)rowIndex
{
    NSString *string = [internalArray objectAtIndex:rowIndex];
    NSLog(@"%@", string);
    // when I debug, I get same pointers with invalid data
    // each object has "name" message
    // this following line gives invalid pointer and
    // it crashes
    return string;
}
@end

In IB I have the tableview (test) hooked up to the app delegate: test, datasource, and delegate

For some reason the table isn’t displaying the data, and when I call [test reloadData]; the app crashes

Answer 1

Number one with a bullet – you don’t retain internalArray after you create it. Use one of:

internalArray = [[NSMutableArray] alloc] init];
internalArray = [[NSMutableArray array] retain];

instead of what you currently have:

internalArray = [NSMutableArray array];

Also, I think you probably don’t want %@ for the format in this method:

-(int)numberOfRowsInTableView:(NSTableView *)aTableView{
    NSLog(@"%@", [internalArray count]);
    return [internalArray count];
}

That code will certainly (well, often) cause a crash when you do [tableView reloadData].

In applicationDidFinishLaunching:, you don’t need to call reloadData every time you add an object to internalArray. Just do it once at the end of that loop.

Your implementation of setObjectValue:forTableColumn:row: also doesn’t make sense. It should look more like this:

-(void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(int)rowIndex
{
    NSLog(@"%@", anObject);
    [internalArray replaceObjectAtIndex:rowIndex withObject:anObject];
}

Hopefully those are some ideas to get you started.