"unrecognized selector sent to instance" after instantiateViewControllerWithIdentifier

Question

This is my code:

- (IBAction) buttonPressed:(id)sender
{
    DestinationViewController *destinationViewController = [[self.storyboard instantiateViewControllerWithIdentifier:@"Destination"] autorelease];
    destinationViewController.title = @"image property";
    destinationViewController.img = [UIImage imageNamed:@"thumbnail"];

    [self.navigationController pushViewController:destinationViewController animated:YES];

    [destinationViewController release];
}

The output is:

2012-07-20 10:43:29.976 jsonimage2[682:f803] 5 - fifth activity -http://i1184.photobucket.com/albums/z328/iElmoTutorials/CrazyEye.png
2012-07-20 10:43:31.878 jsonimage2[682:f803]  The button's image is <UIImage: 0x6aa16c0>.
2012-07-20 10:43:33.846 jsonimage2[682:f803] it works
2012-07-20 10:43:33.861 jsonimage2[682:f803] -[ViewController setImg:]:  unrecognized selector sent to instance 0x68a8b80

First of all, it should be thubnail.extention for example thumbnamil.png. And where are you getting crash? — Nitish, Jul 20 '12 at 05:33
hey have you synthesized your "img object" in destinatioviewcontroller — Leena, Jul 20 '12 at 05:53
Possible duplicate of [How can I debug 'unrecognized selector sent to instance' error](https://stackoverflow.com/questions/25853947/how-can-i-debug-unrecognized-selector-sent-to-instance-error) — Cœur, Jul 08 '19 at 05:51

score 0 · Answer 1 · answered Jul 07 '19 at 15:16

From the doc, instantiateViewControllerWithIdentifier: returns a __kindof UIViewController *.

Your code is attributing it to a DestinationViewController *, but actually it was returning ViewController * according to the crash log. So you probably forgot to set the class of "Destination" correctly in the Storyboard.

score -1 · Answer 2 · answered Jul 20 '12 at 05:33

The line that sets destinationViewController.img would trigger an implicit call to setImg:.

I can't see the definition of DestinationViewController but it apparently does not contain a definition of the img property. You can either implement this by adding an apprpropriate @property for img, or by implementing the setImg: and img methods.

score -1 · Answer 3 · answered Jul 20 '12 at 05:58

-1

you should forget @synthesize img right after @implementation DestinationViewController

answered Jul 20 '12 at 05:58

Kurosawa Hiroyuki

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I synthesize img variable in destinationViewController. – srinu Jul 20 '12 at 08:35
hmm;( maybe i need to see DestinationViewController header – Kurosawa Hiroyuki Jul 20 '12 at 22:31

"unrecognized selector sent to instance" after instantiateViewControllerWithIdentifier

3 Answers3