Error after connecting IBOutlet to UITextField

Question

I'm getting this weird error when I connect an IBOutlet to a UITextField. It's really weird because it's only happening in this one view controller. I have two other view controllers almost identical to this one, and they function perfectly. I have a table view controller in my storyboard. It has 2 grouped sections, each with static cells. Each cell has a UITextField in it. Now, the view loads fine if I just run it without connecting the textfields to my class. However, when I do connect them, as soon as the view loads-the app crashes with this error, one for each textfield: [UITextField stringByTrimmingCharactersInSet:]: unrecognized selector sent to instance

Any idea what the cause of this could be? I'm very confused as I have other tableview controllers with the same contents and I've never gotten this error.

Here are some screenshots to help further explain my situation:

Here is the code for my .m file:

    //
//  IdeaViewController.m
//  FinalJSApp
//
//  Created by Jacob Klapper on 10/20/13.
//
//

#import "IdeaViewController.h"

@interface IdeaViewController ()

@end

@implementation IdeaViewController

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Uncomment the following line to preserve selection between presentations.
    // self.clearsSelectionOnViewWillAppear = NO;

    // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
    // self.navigationItem.rightBarButtonItem = self.editButtonItem;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the specified item to be editable.
    return YES;
}
*/

/*
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete the row from the data source
        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }   
    else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    }   
}
*/

/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/

/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the item to be re-orderable.
    return YES;
}
*/

/*
#pragma mark - Navigation

// In a story board-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}

 */

@end

Answer 1

You declare two properties, title and description, in your view controller that are already defined by UIViewControlller and NSObject respectively. Both of those properties as originally defined are NSStrings.

iOS is probably trying to access those properties, expecting an NSString, and getting one of your UITextFields.

Try renaming those properties and your problem should go away.

Answer 2

You are somehow sending stringByTrimmingCharactersInSet: to a UITextField. But stringByTrimmingCharactersInSet is an instance method of NSString and since UITextField does not implement stringByTrimmingCharactersInSet it gives you the error unrecognized selector sent to instance.