Question

I have a problem while scrolling images on tableview.

I am getting a Signal “0” error.

I think it is due to some memory issues but I am not able to find out the exact error.
The code is as follows,


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

    UITableViewCell *cell = [travelSummeryPhotosTable dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) 
    {           
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]autorelease];

    }

    //Photo ImageView
    UIImageView *photoTag = [[UIImageView alloc] initWithFrame:CGRectMake(5.0, 5.0, 85.0, 85.0)];

    NSString *rowPath =[[imagePathsDictionary valueForKey:[summaryTableViewDataArray objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];

    photoTag.image = [UIImage imageWithContentsOfFile:rowPath];
    [cell.contentView addSubview:photoTag];

    [photoTag release];

    // Image Caption
    UILabel *labelImageCaption = [[UILabel alloc] initWithFrame:CGRectMake(110.0, 15.0, 190.0, 50.0)];
    labelImageCaption.textAlignment = UITextAlignmentLeft;
    NSString *imageCaptionText =[   [imageCaptionsDictionary valueForKey:[summaryTableViewDataArray objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];
    labelImageCaption.text = imageCaptionText;
    [cell.contentView addSubview:labelImageCaption];
    [labelImageCaption release];

    return cell;

}   

Thanks in advance.

Answer 1

Signal “0” error usually means that application crashed because of low memory.

It seems that your problem is the following – you create cell subviews and add them to your cell each time cellForRowAtIndexPath method gets called – so all your allocated UI elements hang in memory and application gets out of it eventually.

To solve your problem you must create cell’s subviews only once – when creating it and later just setup their contents:

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

    UITableViewCell *cell = [travelSummeryPhotosTable dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) 
    {           
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]autorelease];

        UIImageView *photoTag = [[UIImageView alloc] initWithFrame:CGRectMake(5.0, 5.0, 85.0, 85.0)];
        photoTag.tag = 10;
        [cell.contentView addSubview:photoTag];
        [photoTag release];

        UILabel *labelImageCaption = [[UILabel alloc] initWithFrame:CGRectMake(110.0, 15.0, 190.0, 50.0)];
        labelImageCaption.tag = 11;
        labelImageCaption.textAlignment = UITextAlignmentLeft;
        [cell.contentView addSubview:labelImageCaption];
        [labelImageCaption release];
    }

    //Photo ImageView
    NSString *rowPath =[[imagePathsDictionary valueForKey:[summaryTableViewDataArray objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];
    UIImageView* photoTag = (UIImageView*)[cell.contentView viewWithTag:10];
    photoTag.image = [UIImage imageWithContentsOfFile:rowPath];

    // Image Caption
    UILabel *labelImageCaption = (UILabel*)[cell.contentView viewWithTag:11];
    NSString *imageCaptionText =[   [imageCaptionsDictionary valueForKey:[summaryTableViewDataArray objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];
    labelImageCaption.text = imageCaptionText;

    return cell;
}