Aral Balkan

Just got the following error:

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSInvocation setArgument:atIndex:]: index (2) out of bounds [-1, 1]'

While using: UIImageWriteToSavedPhotosAlbum

I was passing in a selector that didn't take any arguments along the lines of:

UIImageWriteToSavedPhotosAlbum([UIImage imageWithData:self.bytes], self, @selector(photoSaved), nil);

Which, if I had read the docs, I would know is wrong, since the function has to conform to the form:

- (void) image: (UIImage *) image
    didFinishSavingWithError: (NSError *) error
    contextInfo: (void *) contextInfo;

Not entirely intuitive perhaps (my expectation is that if a method expects a selector, it shouldn't dictate form and otherwise it should use a delegate; but this being a C-style function we don't have that luxury) hence this blog post in case anyone else runs into the cryptic error and is left scratching their heads.

Solution found courtesy of this post in Japanese (yeah, code's universal!) :)

Comments

• Thanks Aral, I had the same problem and you helped me solve it :)

  by Andrew on 2009-09-29 08:31:35

• Oh yeah...I knew that! Thanks, Aral (+ Google, who listed this post first) for the reminder. I might have gone hours pounding my head against this one....

  by Chris on 2010-11-01 21:43:43

• thanks for referring my blog entry!

  by nishiohirokazu on 2011-07-19 22:49:43

• Great tip! By the way, I was led here by the fact that I had the same kind of error when using UISaveVideoAtPathToSavedPhotosAlbum. It expects an action method of the form - (void)video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo;

  by Andrew on 2012-03-11 23:44:14

• Thanks! I was semi-stumped since the error comes a seemingly random time after the UIImageWriteToSavedPhotosAlbum call.

  by Kirke on 2012-07-08 03:20:35