How to resolve exception -[UIImage scaleToSize:]: unrecognized selector sent to instance

Question

I am getting an image from gallery and displaying it in the collectionViewCell. When user clicks the collectionViewCell that image is dimply into anotherView. I have tableView which is having filters (Effects) to apply when I click tableViewCell. But here I am getting exception. My code is

- (void)viewDidLoad
{
    self.imageView.image = inputImage11;
    self.secImgView.image = secblurImage;

    arrEffects = [[NSMutableArray alloc] initWithObjects:
        [NSDictionary dictionaryWithObjectsAndKeys:@"Original", @"title", @"", @"method", nil],
        [NSDictionary dictionaryWithObjectsAndKeys:@"Brightness", @"title", @"e1", @"method", nil],
        [NSDictionary dictionaryWithObjectsAndKeys:@"BoardWalk", @"title", @"e2", @"method", nil], nil
    ];
    //here getting this Exception
    thumbImage = [inputImage11 scaleToSize:CGSizeMake(300.0f, 300.0f)];
    minithumbImage = [thumbImage scaleToSize:CGSizeMake(40, 40)];
}

I tried googling the issue but have not found a solution. Can anybody please suggest a solution. Thank you in advance.

Where does the inputImage11 come from? Apparently it is supposed to be a UIImage instance which it is not. — Shamas S, Mar 18 '15 at 12:44
i want to display image into collectionViewcell thats why i declared like that — vani lucky, Mar 18 '15 at 12:46
Do you create it as a property in your .h class? Where do you initialize it? Is it created in storyboard? — Shamas S, Mar 18 '15 at 12:48
Where are you getting that scaleToSize is an instance method of UIImage. The doc's don't show any method, class or instance, of that name. Hence you will get a unrecognised selector sent to instance https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIImage_Class/ — Naughty_Ottsel, Mar 18 '15 at 12:49
if i wrote like this thumbImage = [self.imageView.image scaleToSize:CGSizeMake(300.0f,300.0f)]; — vani lucky, Mar 18 '15 at 12:52
i am using third party api for filters and import them into my file then i am using now — vani lucky, Mar 18 '15 at 12:55
What third party api you are using and how you add it? You problem is that this library doesn't implement that — Azat, Mar 18 '15 at 12:57
Is it crashing on the first or second time you are calling `scaleToSize`? — Mika, Mar 18 '15 at 12:58
So if you comment `thumbImage = [inputImage11 scaleToSize:CGSizeMake(300.0f, 300.0f)];` you get no exception? — Mika, Mar 18 '15 at 13:03
possible duplicate of [How can I debug 'unrecognized selector sent to instance' error](http://stackoverflow.com/questions/25853947/how-can-i-debug-unrecognized-selector-sent-to-instance-error) — Hot Licks, Mar 18 '15 at 13:11
The problem is quite simple. **UIImage does not have a method named `scaleToSize:`.** — Hot Licks, Mar 18 '15 at 13:15
@HotLicks author has mentioned that he is using 3d party library but didn't said which one — Azat, Mar 18 '15 at 13:21
@Azat - Hopefully UIImage is not a 3rd-party class, since it's an essential class in iOS. — Hot Licks, Mar 18 '15 at 17:46
The message is telling you that you're attempting to use the method `scaleToSize:` on an object of class UIImage, and there is no such method on that class. The most obvious reason for this would be that either `inputImage11` or `thumbImage` (or both) is a UIImage rather than some subclass of UIView. — Hot Licks, Mar 18 '15 at 17:50
@iosDev82 - Your comment is backwards. The problem is that at least one of those two `...Image` pointers *is* pointing at a UIImage. — Hot Licks, Mar 18 '15 at 17:52
i am using image filters third party api files those are UIImage+Filttr.h, .m, — vani lucky, Mar 19 '15 at 05:32
UIImage+FilterCompositions.h,UIImage+FilterCompositions.m , UIImage+Scale.h — vani lucky, Mar 19 '15 at 05:34

score 0 · Answer 1 · answered Mar 18 '15 at 13:25

0

Just replace your line with the following:

thumbImage = [self imageWithImage:inputImage11 scaleToSize:CGSizeMake(300.0f, 300.0f)];

And add this method to your class:

- (UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize {
    //UIGraphicsBeginImageContext(newSize);
    // In next line, pass 0.0 to use the current device's pixel scaling factor (and thus account for Retina resolution).
    // Pass 1.0 to force exact pixel size.
    UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
    [image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();    
    UIGraphicsEndImageContext();
    return newImage;
}

Credit: @Paul Lynch for the method.

Also, these are some categories you should look at: http://vocaro.com/trevor/blog/2009/10/12/resize-a-uiimage-the-right-way/

answered Mar 18 '15 at 13:25

Mika

5,807
6
38
83

getting error like NO visible @interface secondViewController declares the selector imageWithImage:scaleToSize:' – vani lucky Mar 19 '15 at 05:23
You need to put the method in the same view controller where you are calling it. If not you need to create a helper class. – Mika Mar 19 '15 at 09:50
i want to call this method in same viewController..actaully my requirement is i have an image in viewController which having tableView also so when we click tableviewCell we want to apply filter effect to image..similarly when i click another tableviewcell some other filter effect will be applied .. – vani lucky Mar 19 '15 at 10:01
Dude there is nothing in your code above about filters. You asked about scaling to fit and I showed you how to do that. – Mika Mar 19 '15 at 11:30

How to resolve exception -[UIImage scaleToSize:]: unrecognized selector sent to instance

1 Answers1