Question

I hope someone can help with this.

I have a UITableViewController and want to pass a value to a UIViewController called NewsArticleViewController when the tablecell is selected. I’ve created a segue from the tablecell to the view controller.

When I call my prepareForSegue method below:

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if([[segue identifier] isEqualToString:@"ShowNewsArticle"])
    {
        NSIndexPath *indexPath = [self._tableView indexPathForSelectedRow];
        NSDictionary *article = [_articles objectAtIndex:indexPath.row];
        NSString *articleID = [article valueForKey:@"id"];
        NSLog(@"Trying %@", articleID);

        NewsArticleViewController *detailViewController = [segue destinationViewController];
        detailViewController.articleID = articleID;
    }
}

The NSLog shows the NSString value correctly before the error occurs on the last line.

I get the error:

2012-12-11 23:08:41.915 My School[4689:c07] -[UIViewController setArticleID:]: unrecognized selector sent to instance 0x8088140
2012-12-11 23:08:41.916 My School[4689:c07] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIViewController setArticleID:]: unrecognized selector sent to instance 0x8088140'
*** First throw call stack:
(0x1800012 0x11c5e7e 0x188b4bd 0x17efbbc 0x17ef94e 0x3ca1 0x554ac7 0x554b54 0x1bc899 0x1bcb3d 0xbc3e83 0x17bf376 0x17bee06 0x17a6a82 0x17a5f44 0x17a5e1b 0x1cc87e3 0x1cc8668 0x10d65c 0x1f4d 0x1e75 0x1)
libc++abi.dylib: terminate called throwing an exception

On the destination view controller, NewsArticleViewController, I have declared this in the header:

@property(strong,nonatomic) id articleID;

And I have synthesized the property in the method. I’m using ARC, I don’t know if this is the specific cause but I can’t proceed until I sort this out. Thanks.

Answer 1

In your error message, UIViewController is reporting the “unrecognized selector” error. I suspect your storyboard has not specified your custom NewsArticleViewController for this scene. Thus, it’s using the default UIViewController which obviously doesn’t understand the setArticleID.

Check the “Custom Class” setting for the view controller in Interface Builder:

If the custom class has not specified, it will look like the above screen snapshot. Just fill in the class name.