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iOS Build a Blog Reader iPhone App Exploring the Master-Detail Template Passing Data To The Detail View

Returns error on Xcode 7.0

When press item returns: 2015-10-19 12:27:52.899 BlogReader[4138:232343] -[UINavigationController setDetailItem:]: unrecognized selector sent to instance 0x7ff944831600 (lldb)

1 Answer

Yup. The video is pretty old. (It's from 2012!) The code that'll work is this:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    if ([[segue identifier] isEqualToString:@"showDetail"]) {

        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow]; // Sets the index path
        NSString *object = [ _titlesArray objectAtIndex: [ indexPath row ] ]; // Sets the title of blog as the variable object

        // You need to cast the destination view controller as a DetailViewController, or else it'll give an ugly error...

        DetailViewController *controller = (DetailViewController *)[[segue destinationViewController] topViewController];
        [controller setDetailItem:object];

        /* This just sets the nav bar of the destination view controller to have a button that can change the display of the view controller.
         Only introduced in iOS 8

        controller.navigationItem.leftBarButtonItem = self.splitViewController.displayModeButtonItem;
        controller.navigationItem.leftItemsSupplementBackButton = YES;