dismissModalViewControllerAnimated crashes app - iphone

Question

I am new to iPhone development, so please pardon my ignorance.
I call a UIViewController from a UIViewController. The first UIViewController is a list of items, and the second is the detail for each of the items.
ListViewController (first UIViewController):
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
// initialize a AddViewController
selItem = indexPath.row;
selIndexPath = indexPath;
AddViewController *controller = [[AddViewController alloc] init];
// give controller the data to display
// show the AddViewController
[controller setData:[list objectAtIndex:indexPath.row]];
controller.delegate = self;
[self presentModalViewController:controller animated:YES];
[controller release]; // release the controller AddViewController
} // end method tableView:didSelectRowAtIndexPath:
In the 'AddViewController' I have a segment control as both the left and right button bars. On the left, I have 'Exit' and 'Delete'. On the right I have 'Add' and 'Save'. The outlets that the segment controls are linked to are:
AddViewController (second UIViewController):
- (IBAction)delExitSegment:sender
{
// The segmented control was clicked, handle it here
UISegmentedControl *segmentedControl = (UISegmentedControl *)sender;
switch (segmentedControl.selectedSegmentIndex) {
case 0: // Exit Button
[delegate addViewControllerDidExit:self];
break;
case 1: // Delete Button
[delegate addViewControllerDelItem:self];
break;
}
}
- (IBAction)segmentAction:sender
{
// The segmented control was clicked, handle it here
UISegmentedControl *segCtl = (UISegmentedControl *)sender;
switch (segCtl.selectedSegmentIndex) {
case 0: // Add Button
if (currentCell != nil)
[data setValue:currentCell.textField.text forKey:currentCell.label.text];
[delegate addViewControllerDidFinishAdding:self];
break;
case 1: // Save Button
[delegate addViewControllerUpdate:self];
break;
}
}
When I come back to my first view controller, I have:
ListViewController:
- (void)addViewControllerDidFinishAdding:(AddViewController *)controller
{
NSDictionary *item = [controller values];
if (item != nil)
{
[list addObject:item];
}
[self dismissModalViewControllerAnimated:YES];
[list writeToFile:itemFilePath atomically:NO];
[self calcTotal];
[self.tableView reloadData];
}
- (void)addViewControllerUpdate:(AddViewController *)controller
{
NSDictionary *item = [controller values];
if (item != nil)
{
[list replaceObjectAtIndex:selItem withObject:item];
}
[self dismissModalViewControllerAnimated:YES];
[list writeToFile:itemFilePath atomically:NO];
[self calcTotal];
[self.tableView reloadData];
}
- (void)addViewControllerDidExit:(AddViewController *)controller
{
[self dismissModalViewControllerAnimated:YES];
[self.tableView reloadData];
}
- (void)addViewControllerDelItem:(AddViewController *)controller
{
NSDictionary *item = [controller values];
if (item != nil)
{
[list removeObjectAtIndex:selItem];
[self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:selIndexPath] withRowAnimation:UITableViewRowAnimationFade];
[list writeToFile:itemFilePath atomically:NO];
}
[self dismissModalViewControllerAnimated:YES];
[self.tableView reloadData];
}
If I exit or delete an item from AddViewController, I have no problems. When I try and add or save, then my application will crash. The debugger crashes at dismissModalViewControllerAnimated. I can't see what's different between the two segment controls.
Any ideas what I may have wrong?
I just discovered that neither the left or right buttons work when I attempt to edit a cell. The editing cell in AddViewController is as follows:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *identifier = #"EditableCell";
EditableCell *cell = (EditableCell *)[table dequeueReusableCellWithIdentifier:identifier];
if (cell == nil)
{
cell = [[EditableCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier];
}
NSString *key = [fields objectAtIndex:indexPath.row + indexPath.section * 3];
[cell setLabelText:key];
cell.textField.text = [data valueForKey:key];
if (indexPath.section == 0 && (indexPath.row == 1 || indexPath.row == 3))
cell.textField.keyboardType = UIKeyboardTypeNumberPad;
if (indexPath.section == 1)
cell.textField.keyboardType = UIKeyboardTypeNumberPad;
cell.editing = NO;
cell.delegate = self;
cell.selectionStyle = UITableViewCellSelectionStyleNone;
return cell;
}

Answer 1

Here is the problem:
[self dismissModalViewControllerAnimated:YES];
[self.tableView reloadData];
When you dismiss the view the value of self become unknown, accessing the tableview will definitely crash.
If you want to refresh the tableView just use [self.tableView reloadData] and don't dismiss the view.