title: How to not copy images into UITextView
body: <p>My app uses <code>UITextView</code> to get some input from user, I use Xcode4.5 simulator for Ipad 5.1 , ARC </p>
  
  <p>If user tries to copy&amp;paste a text with  bulletining or image ,  I get following error:</p>
  
  <pre><code> Mapping '/Users/user/Library/Application Support/iPhone Simulator/5.1/Library/Caches/com.apple.keyboards/images/1848901318' failed: 'Cannot allocate memory' (12)
  
  GuardMalloc[W]: Failed to VM allocate 16384 bytes
  GuardMalloc[W]: Explicitly trapping into debugger!!!
  </code></pre>
  
  <p>I tired below to user to prevent using any odd chars or images from pasting but couldnt make it work, it doesnt even fire. </p>
  
  <pre><code>- (void)paste:(id)sender {
      UIPasteboard *pasteBoard = [UIPasteboard generalPasteboard];
      NSString *string = pasteBoard.string;
      NSLog(@"Pasteboard string: %@", string);
      [self.wodDescription insertText:string]; //woddesription is the textview
  }
  </code></pre>
  
  <p>Why do I get above error? What is the best way to fix this crash? </p>