NSMutableArray doesn't store any object

Question

My NSMutableArray doesn't store any object, either a String or a complex class. I tried it to allocate ind init and to init as an array. Both without success.

.m file:

@interface WorkCentersViewController()
@property (nonatomic, retain) NSMutableArray *selectedWorkCenters;
@end


@implementation WorkCentersViewController
@synthesize selectedWorkCenters;


-(id)init{

    self = [super init];

    if(self){


        //self.selectedWorkCenters = [[NSMutableArray alloc] init]; //doesn't work too
        self.selectedWorkCenters = [NSMutableArray array];

    }
    return self;
}

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


- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
    if(cell.accessoryType == UITableViewCellAccessoryCheckmark){      
        ...
    }else{
        //select
        cell.accessoryType = UITableViewCellAccessoryCheckmark; 
        //add
        [self.selectedWorkCenters addObject:[self.workCenters objectAtIndex:indexPath.row]];
        NSLog(@"Sel WC Count: %d", [self.selectedWorkCenters count]); //always 0
    }
}

Why is it not storing my object of WorkCenter? What I'm doing wrong?

BR, mybecks

Mark Leonard · Accepted Answer · 2011-12-12 16:22:54Z

1

Perhaps that specific init method isn't being called? Is this a UITableViewController? Maybe you're initializing it with initWithStyle:? I'd set a break point on the line where you init the array just to check.

answered Dec 12, 2011 at 16:22

Mark Leonard

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3 Comments

mybecks Over a year ago

I call it from the RootViewController:

- (void) insertNewWorkplace {     NSLog(@"Add new workplace");     WorkCentersViewController *workCentersController = [[WorkCentersViewController alloc] init];     [self.navigationController pushViewController:workCentersController animated:YES];     [workCentersController release]; }

Yes it is a TableViewController. The init Method is called, I tested it with a Brreakpoint before.

Mark Leonard Over a year ago

Set a breakpoint or use NSLog in the init just to make sure. Also I'd make certain that the object you are trying to add to the array isn't nil.

mybecks Over a year ago

My Object is not null, I test it with NSLOg. My output of NSLog in viewDidLoad is ( ).

Ben Mosher · Accepted Answer · 2011-12-12 16:37:50Z

0

-initWithNibName:bundle: is UIViewController's designated initializer, so any init code should show up in an override of that method. If this is a subclass of UITableViewController, Mark is correct that initWithStyle is a good place to put it.

Also, in general, viewDidLoad/viewDidUnload give you a good place to alloc/dealloc data structures that your view needs, but that can be recreated if needed.

answered Dec 12, 2011 at 16:37

Ben Mosher

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2 Comments

mybecks Over a year ago

I added my init code of the NSMutableArray to the viewDidLoad method. But won't works either with [[... alloc] init] and [NSMutableArray array]

Ben Mosher Over a year ago

NSLog both arrays (workCenters and selected...) and see what you find. Perhaps workCenters is nil?

Adam Kaump · Accepted Answer · 2011-12-12 16:41:32Z

0

Try initializing your NSMutableArray in this way:

self.selectedWorkCenters = [[NSMutableArray alloc] init];

answered Dec 12, 2011 at 16:41

Adam Kaump

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Comments

Rafał Sroka · Accepted Answer · 2011-12-12 21:23:25Z

0

Ok so here are my ideas. In your init you are using:

// This one is wrong, you are [NSMutableArray array] returns a NSArray which cannot be 
// mutated so you cannot add objects to it. That is why it is not working.
//
self.selectedWorkCenters = [NSMutableArray array];

// This one is wrong because you have a leak here (Although it should work)
//
self.selectedWorkCenters = [[NSMutableArray alloc] init];

Try this:

selectedWorkCenters = [[NSMutableArray alloc] init];

And place it in the viewDidLoad method. Hope it helps. Let me know :)

answered Dec 12, 2011 at 21:23

Rafał Sroka

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Comments

mybecks · Accepted Answer · 2011-12-14 12:52:44Z

0

I have found the error.

In a other method I had the assignment

selectedWorkCenters = availableWorkCenters;

availableWorkCenters wasn't initialized - always 0x0 in the debugger screen.

answered Dec 14, 2011 at 12:52

mybecks

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