iOS6 UIPickerView memory leak issue.

Question

I was getting this memory leak:

[UIPickerTableViewTitleCell initWithStyle:resuableIdentifier]; 

and

NSConcentrateMutableAttributedString.

Issue was that I had not implemented this delegate. After implementing this now memory leaks goes away. May be this information helpful for other as I spend mine 16 hours only to figure out this issue.

// Do something with the selected row.
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view {

// Get the text of the row.
NSString *rowItem = [NSString stringWithFormat:@"     %@",[machineData objectAtIndex:row]];

// Create and init a new UILabel.
// We must set our label's width equal to our picker's width.
// We'll give the default height in each row.
UILabel *lblRow = [[UILabel alloc] initWithFrame:CGRectMake(0.0f, 0.0f, [pickerView bounds].size.width, 44.0f)];

// Make the text color red.
[lblRow setTextColor: [UIColor blackColor]];
[lblRow setFont:[UIFont boldSystemFontOfSize:20]];

// Center the text.
[lblRow setTextAlignment:UITextAlignmentLeft];

// Add the text.
[lblRow setText:rowItem];

// Clear the background color to avoid problems with the display.
[lblRow setBackgroundColor:[UIColor clearColor]];

// Return the label.
return lblRow;
}

Answer 1

Thanks for your info. Was confused by this leak. Only few comments:

• probably lblRow should be autoreleased: return [lblRow autorelease];

• [pickerView rowSizeForComponent:component] can be used to get size for new label.

Answer 2

I used IUIPicker in a popover and every time I dismissed the popover I had memory leak. I am also using ARC, so the easiest way I resolved this was by setting the UIPickerView = nil on unload. The following appears to have done the trick.

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
    self.pickerView = nil;
}