NSTableView data source editing

Question

I'm just a beginner in Cocoa developing for Snow Leopard and I have problem with editing values in data array that displayed in NSTableView.

I tried to edit some property of my object in -tableView:setObjectValue:forTableColumn:row: and I have EXC_BAD_ACCESS after this.

My NSTableView contains one column with NSButtonCell cells and this column have identifier 'checked'.

My code is simple and looks like this:

@interface MyObj: NSObject {
    BOOL checked;
}
@property (assign) BOOL checked;
@end

@imlpementation MyObj
@synthesize checked;
@end

@interface MyAppDelegate: NSObject <NSApplicationDelegate, NSTableViewDelegate, NSTableViewDataSource> {
    NSMutableArray *data;
    NSTableView *table;
}

@property (assign) IBOutlet NSTableView *table;
- (NSInteger) numberOfRowsInTableView:(NSTableView *)aTableView;
- (id) tableView:(NSTableView *)aTableView objectValueForTableColumn:(NSTableColumn *)aTableColumn row:(NSInteger)rowIndex;
- (void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(NSInteger)rowIndex;

@end

@implementation MyAppDelegate

@synthesize table;

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
    data = [[NSMutableArray array] retain];

        // some code that add few objects to data
        // each object is instance of MyObj and I call alloc+init+retain for each
        // ...

    [table reloadData];
}

- (void)dealloc {
    [data release];
    [super dealloc];
}

- (NSInteger) numberOfRowsInTableView:(NSTableView *)aTableView {
    return (data == nil ? 0 : [data count]);
}

- (id) tableView:(NSTableView *)aTableView objectValueForTableColumn:(NSTableColumn *)aTableColumn row:(NSInteger)rowIndex {
    MyObj *obj;
    obj = [data objectAtIndex:rowIndex];
    NSString *identifier;
    identifier = [aTableColumn identifier];
    return [obj performSelector:NSSelectorFromString(identifier)];
}

- (void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(NSInteger)rowIndex {
    MyObj *obj;
    obj = [data objectAtIndex:rowIndex];
    NSString *identifier;
    identifier = [aTableColumn identifier];
    if ([identifier isEqualTo:@"checked"]) {
        BOOL value = [anObject boolValue];
        obj.checked = value;
        [data replaceObjectAtIndex:rowIndex withObject:obj];
    }

    [table reloadData];
}

@end

And I have raised objc_msgSend_vtable5 from -[NSButtonCell setObjectValue] method.

Answer 1

I found solution for my problem. I changed BOOL checked to NSNumber *checked.

- (void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(NSInteger)rowIndex {
    MyObj *obj = (MyObj *)[data objectAtIndex:rowIndex];
    NSString *identifier;
    identifier = [aTableColumn identifier];

    if ([identifier isEqualTo:@"checked"]) {
        [obj setValue:[[NSNumber numberWithBool:[anObject boolValue]] retain] forKey:[aTableColumn identifier]];
    }

    [table reloadData];
}

And all works fine right now. I hope it helps someone.