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When converting a project to use ARC what does "switch case is in protected scope" mean?

When converting a project to use ARC what does "switch case is in protected scope" mean? I am converting a project to use ARC, using Xcode 4 Edit -> Refactor -> Convert to Objective-C ARC... One of the errors I get is "switch case is in protected scope" on "some" of the switches in a switch case.

Edit, Here is the code:

the ERROR is marked on the "default" case:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"";
    UITableViewCell *cell ;
    switch (tableView.tag) {
        case 1:
            CellIdentifier = @"CellAuthor";
            cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
            if (cell == nil) {
                cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
        }
        cell.textLabel.text = [[prefQueries objectAtIndex:[indexPath row]] valueForKey:@"queryString"];
        break;
    case 2:
        CellIdentifier = @"CellJournal";
        cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
        }
        cell.textLabel.text = [[prefJournals objectAtIndex:[indexPath row]] valueForKey:@"name"];

        NSData * icon = [[prefJournals objectAtIndex:[indexPath row]] valueForKey:@"ico开发者_StackOverflow社区n"];
        if (!icon) {
            icon = UIImagePNGRepresentation([UIImage imageNamed:@"blank72"]);
        }
        cell.imageView.image = [UIImage imageWithData:icon];

        break;

    default:
        CellIdentifier = @"Cell";
        cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
            cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
            }
        break;
    }


    return cell;
}


Surround each case itself with braces {}. That should fix the issue (it did for me in one of my projects).


Hard to be sure without looking at the code, but it probably means there's some variable declaration going on inside the switch and the compiler can't tell if there's a clear path to the required dealloc point.


There are 2 easy ways to solve this issue:

  • You are probably declaring variables. Move the declaration of the variables outside the switch statement
  • Put the whole case block in between curly brackets {}

The compiler can not calculate the code line when the variables are to be released. Causing this error.


For me, the problem started on the middle of a switch and curly brackets did not worked out, unless you have to include {} IN ALL previous case statements. For me the error came when I had the statement

NSDate *start = [NSDate date];

in the previous case. After I deleted this, then all subsequent case statement came clean from the protected scope error message


Before:

    case 2:
        NSDate *from = [NSDate dateWithTimeIntervalSince1970:1388552400];
        [self refreshContents:from toDate:[NSDate date]];
        break;

I moved NSDate definition before switch, and it fixed the compile problem:

NSDate *from;  /* <----------- */
switch (index) {
    ....
    case 2:
        from = [NSDate dateWithTimeIntervalSince1970:1388552400];
        [self refreshContents:from toDate:[NSDate date]];
        break;

}


Declare the variables outside the switch, then instantiate them inside the case. That worked perfectly for me using Xcode 6.2


default:
        CellIdentifier = @"Cell";
        cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            ***initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];***
            cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
            }
        break;
    }

Note: Check! The syntax of the bold & italicized line. Rectify it and you are good to go.


Surround with braces {} the code between the case statement and the break in each case. It worked on my code.

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