Question

With the delegate and datasource connections made, I have the following controller:

#import <Foundation/Foundation.h>

@interface KextTable : NSObject <NSTableViewDataSource> {
@private
    NSArray *klist;
}
- (int)numberOfRowsInTableView:(NSTableView *)tableView;
- (id)tableView:(NSTableView *)tableView
objectValueForTableColumn:(NSTableColumn *)tableColumn
            row:(int)row;
@end

and

#import "KextTable.h"


@implementation KextTable

- (id)init
{
    self = [super init];
    if (self) { 
}    
    return self;
}

-(void) awakeFromNib 
{
    klist = [[NSArray alloc] init];

    klist = [NSArray arrayWithObjects: @"1", @"2",
             @"3", @"4", nil]; // debugging values only
}

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

- (int)numberOfRowsInTableView:(NSTableView *)tableView
{
    return [klist count];
}

- (id)tableView:(NSTableView *)tableView
objectValueForTableColumn:(NSTableColumn *)tableColumn
            row:(int)row
{
    return [klist objectAtIndex:row];
}

@end

And this code is crashing with EXC_BAD_ACCESS in my main interface control where the view is switched to the tab containing the table view. What is wrong?

(I know that connections are right, if I create the array in objectValueForTableColumn it works)

Answer 1

It’s because the klist you’re creating (the debug one) is using the constructor that autoreleases it. So you should add in:

klist = [[NSArray arrayWithObjects: @"1", @"2", @"3", @"4", nil] retain];

Be sure to note that in what you’ve done there’s a memory leak (you create an NSArray and then re-assign the variable to something else…)