[__NSCFArray length]: unrecognized selector sent to instance

Question

I'm creating a iWatch app in which I need to display an array of images. I'm using WCSession to transfer the images from the iPhone. Here is the code I tried:

InterfaceController.m

- (void)willActivate {
    [super willActivate];

   if ([WCSession isSupported]) {

    WCSession *session = [WCSession defaultSession];
    session.delegate = self;
    [session activateSession];

    NSLog(@"WCSession is supported");
}

- (void)session:(WCSession *)session didReceiveApplicationContext:(NSDictionary<NSString *,id> *)applicationContext {
    NSLog(@"%@", applicationContext);

    NSData *imageData = applicationContext[@"image"];
    UIImage *contactImage = [UIImage imageWithData:imageData];
    _graphImage = [contactImage valueForKey:@"image"];
}

In my iPhone app, I have an array which stores the images in bytes. After executing the iWatch app, I'm getting the NSData value from my iPhone app. But the app terminates at UIImage *contactImage = [UIImage imageWithData:imageData]; with

[__NSCFArray length]: unrecognized selector sent to instance.

I googled this error but not able to find a solution in my case.

Any help will be greatly appreciated.

If you're new, why not learn Swift? Type checking would make your code more safe and `as?` would have avoided a crash from such an error. — , Mar 25 '16 at 13:18
@dan yes actually the applicationContext contains the response from iphone app. So imageData is actually an NSArray — Jestin Saji Chacko, Mar 25 '16 at 13:27

Karaban · Accepted Answer · 2016-03-25T13:28:43.693

-1

You're getting this error because there is missplaced type -_graphImage = [contactImage valueForKey:@"image"]; - here your are sending valueForKey for image instance

edited Mar 25 '16 at 13:28

answered Mar 25 '16 at 13:19

Karaban

151
8

then how can i set the value in _graphImage – Jestin Saji Chacko Mar 26 '16 at 07:06
i solved it.. i deleted this UIImage *contactImage = [UIImage imageWithData:imageData]; and set the NSData value directly to _graphImage.. it worked for me.. Thanks for your help @ Karaban – Jestin Saji Chacko Mar 26 '16 at 07:40
[_graphImage setImageData:imageData]; – Jestin Saji Chacko Mar 28 '16 at 10:51

[__NSCFArray length]: unrecognized selector sent to instance

1 Answers1