Question

I am trying to figure out this error from previous 3 hours. By searching, I have come to know that this error is related to memory management, but I have failed to figure out that what I am doing wrong.

I have declared these 4 labels:

@interface InteractiveHistory : UITableViewController {
UILabel *date;
UILabel *startTime;
UILabel *cal;
UILabel *duration;
}

Then created properties and synthesized them. In viewDidLoad, I initialized all like this one:

date = [[UILabel alloc] init];

I also have deallocated them in dealloc() method.

What I want to do is use these 4 labels to write some text in cells of the table. Text will depend upon the indexPath.

In cellForRowAtIndexPath method, just showing you for 2 labels and have indicated error line:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];

        NSLog(@"constructing cell");

        //set up labels text

        date = [NSString stringWithFormat:@"%@",[[int_data objectAtIndex:indexPath.row] objectForKey:@"Date"]];


 NSLog(@"%@",date.text); //App crashes at this line
       [date setTag:1];


        startTime = [NSString stringWithFormat:@"%@",[[int_data objectAtIndex:indexPath.row] objectForKey:@"Start Time"]]; 

        //setting tag and position of label
        [startTime setTag:2];
        CGRect labelpos =  startTime.frame;
        labelpos.origin.y = date.bounds.size.height + 2;
        startTime.frame = labelpos;

        NSLog(@"labels set");

   // Configure the cell...
    [[cell contentView] addSubview:date];
    [[cell contentView] addSubview:startTime];
    [[cell contentView] addSubview:duration];
    [[cell contentView] addSubview:cal];


    NSLog(@"A cell set");

    }      

    return cell;
}

Can anybody plz tell me what am I doing wrong? I hope my Question is clear..

Answer 1

The line:

date = [NSString stringWithFormat:@"%@",[[int_data objectAtIndex:indexPath.row] objectForKey:@"Date"]];

should be:

date.text = [NSString stringWithFormat:@"%@",[[int_data objectAtIndex:indexPath.row] objectForKey:@"Date"]];

Otherwise your date pointer is set to an instance of an NSString, instead of setting its contents.

Edit:

As danh correctly points out, you will have the same problem with startTime.