title: UIImage imageNamed returns nil except for the first image
body: <p>I'm loading images from my app's image.xcassets using <code>[UIImage imageNamed:@"filename"]</code> method and <strong>only the first image is loading correctly</strong> but then the rest of the images returns nil and crashes the app. Below is my code:</p>
  
  <pre><code>[self.imagePicker addImage:[UIImage imageNamed:@"image0-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image1-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image2-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image3-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image4-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image5-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image6-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image7-150x277"]];
  [self.imagePicker addImage:[UIImage imageNamed:@"image8-150x277"]];
  </code></pre>
  
  <p>And here is my addImage method:</p>
  
  <pre><code>- (void)addImage:(UIImage *)image 
  {
      [_images addObject:image];
      [_thumbs addObject:image];
  }
  </code></pre>
  
  <p>I have checked this <a href="https://stackoverflow.com/questions/10998544/uiimage-imagenamed-returns-nil">question</a> and tried everything in it including file names check and making sure the images are Retina 2x but nothing worked.
  Any ideas on what might be wrong?</p>
  
  <p>And here is the crash log:</p>
  
  <p><code>2016-10-14 15:28:10.280 Munasabah[38773:1038198] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[__NSArrayM insertObject:atIndex:]: object cannot be nil'
  *** First throw call stack:
  (
      0   CoreFoundation                      0x000000010d65134b __exceptionPreprocess + 171
      1   libobjc.A.dylib                     0x000000010d0b221e objc_exception_throw + 48
      2   CoreFoundation                      0x000000010d58238f -[__NSArrayM insertObject:atIndex:] + 1375
      3   Munasabah                           0x0000000108dcb669 -[CustomImagePicker addImage:] + 73
      4   Munasabah                           0x0000000108dc8012 -[FlipsideViewController viewDidLoad] + 994
      5   UIKit                               0x000000010b4cd06d -[UIViewController loadViewIfRequired] + 1258
      6   UIKit                               0x000000010b4cd4a0 -[UIViewController view] + 27
      7   UIKit                               0x000000010bd918d0 -[_UIFullscreenPresentationController _setPresentedViewController:] + 87
      8   UIKit                               0x000000010b4a7d26 -[UIPresentationController initWithPresentedViewController:presentingViewController:] + 141
      9   UIKit                               0x000000010b4e030b -[UIViewController _presentViewController:withAnimationController:completion:] + 3956
      10  UIKit                               0x000000010b4e36df -[UIViewController _performCoordinatedPresentOrDismiss:animated:] + 530
      11  UIKit                               0x000000010b4e31c5 -[UIViewController presentViewController:animated:completion:] + 179
      12  Munasabah                           0x0000000108dc7632 -[MainViewController showInfo:] + 354
      13  UIKit                               0x000000010b32db88 -[UIApplication sendAction:to:from:forEvent:] + 83
      14  UIKit                               0x000000010b4b32b2 -[UIControl sendAction:to:forEvent:] + 67
      15  UIKit                               0x000000010b4b35cb -[UIControl _sendActionsForEvents:withEvent:] + 444
      16  UIKit                               0x000000010b4b24c7 -[UIControl touchesEnded:withEvent:] + 668
      17  UIKit                               0x000000010b39b0d5 -[UIWindow _sendTouchesForEvent:] + 2747
      18  UIKit                               0x000000010b39c7c3 -[UIWindow sendEvent:] + 4011
      19  UIKit                               0x000000010b349a33 -[UIApplication sendEvent:] + 371
      20  UIKit                               0x000000010bb3bb6d __dispatchPreprocessedEventFromEventQueue + 3248
      21  UIKit                               0x000000010bb34817 __handleEventQueue + 4879
      22  CoreFoundation                      0x000000010d5f6311 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
      23  CoreFoundation                      0x000000010d5db59c __CFRunLoopDoSources0 + 556
      24  CoreFoundation                      0x000000010d5daa86 __CFRunLoopRun + 918
      25  CoreFoundation                      0x000000010d5da494 CFRunLoopRunSpecific + 420
      26  GraphicsServices                    0x000000010f712a6f GSEventRunModal + 161
      27  UIKit                               0x000000010b32bf34 UIApplicationMain + 159
      28  Munasabah                           0x0000000108dc430e main + 62
      29  libdyld.dylib                       0x000000010df2c68d start + 1
  )
  libc++abi.dylib: terminating with uncaught exception of type NSException
  (lldb)</code> </p>
  
  <p>And a screen shot for the target membership:</p>
  
  <p><a href="https://i.stack.imgur.com/OmhZ5.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OmhZ5.png" alt="enter image description here"></a></p>