title: iOS6 NSMutableAttributedString addAttribute:value:range: not working
body: <p>My environment: Xcode 4.5.2, iOS 6.0 SDK</p>
  
  <p>At first, I made a simple project with UITextView and Attribuded String by using IB.
  <img src="https://i.stack.imgur.com/80urk.png" alt="enter image description here">
  Then, run iOS Simulator, works fine.
  <img src="https://i.stack.imgur.com/7vGUB.png" alt="enter image description here"> </p>
  
  <p>Second, I tried to using attributes by cording. The code is like this.</p>
  
  <p>ViewController.h:</p>
  
  <pre><code>@property (strong, nonatomic) IBOutlet UITextView *textView;
  </code></pre>
  
  <p>ViewController.m:</p>
  
  <pre><code>[super viewDidLoad];
  
  UIFont *font = [UIFont systemFontOfSize:14.0f];
  NSMutableDictionary *attrsDictionary = [NSMutableDictionary dictionaryWithObject:font forKey:NSFontAttributeName];
  
  NSMutableParagraphStyle *paragraphStyle = [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
  [attrsDictionary setObject:paragraphStyle forKey:NSParagraphStyleAttributeName];
  
  NSString *text = @"In iOS 6 and later, this class supports multiple text styles through use of the attributedText property.";
  
  NSMutableAttributedString *attributedText = [[NSMutableAttributedString alloc] initWithString:text attributes:attrsDictionary];
  
  NSRange range = NSMakeRange(3, 5); // range of "iOS 6"
  [attributedText addAttribute:NSForegroundColorAttributeName value:[UIColor colorWithRed:0.262745 green:0.262745 blue:0.262745 alpha:1] range:range];
  
  self.textView.attributedText = attributedText;
  </code></pre>
  
  <p>The result was not working correctly.
  <img src="https://i.stack.imgur.com/OP99P.png" alt="enter image description here"></p>
  
  <p>So, I tried to get log.</p>
  
  <pre><code>NSLog(@"%@", self.textView.attributedText);
  
  In {
      NSColor = "UIDeviceRGBColorSpace 0 0 0 1";
      NSFont = "&lt;UICFFont: 0x716eef0&gt; font-family: \".Helvetica NeueUI\"; font-weight: normal; font-style: normal; font-size: 14px";
      NSKern = 0;
      NSParagraphStyle = "Alignment 4, LineSpacing 0, ParagraphSpacing 0, ParagraphSpacingBefore 0, HeadIndent 0, TailIndent 0, FirstLineHeadIndent 0, LineHeight 0/0, LineHeightMultiple 0, LineBreakMode 0, Tabs (\n), DefaultTabInterval 36, Blocks (null), Lists (null), BaseWritingDirection 0, HyphenationFactor 0, TighteningFactor 0, HeaderLevel 0";
      NSStrokeColor = "UIDeviceRGBColorSpace 0 0 0 1";
      NSStrokeWidth = 0;
  }iOS 6{
      NSColor = "UIDeviceRGBColorSpace 0.262745 0.262745 0.262745 1";
      NSFont = "&lt;UICFFont: 0x716eef0&gt; font-family: \".Helvetica NeueUI\"; font-weight: normal; font-style: normal; font-size: 14px";
      NSKern = 0;
      NSParagraphStyle = "Alignment 4, LineSpacing 0, ParagraphSpacing 0, ParagraphSpacingBefore 0, HeadIndent 0, TailIndent 0, FirstLineHeadIndent 0, LineHeight 0/0, LineHeightMultiple 0, LineBreakMode 0, Tabs (\n), DefaultTabInterval 36, Blocks (null), Lists (null), BaseWritingDirection 0, HyphenationFactor 0, TighteningFactor 0, HeaderLevel 0";
      NSStrokeColor = "UIDeviceRGBColorSpace 0.262745 0.262745 0.262745 1";
      NSStrokeWidth = 0;
  } and later, this class supports multiple text styles through use of the attributedText property.
  ...
  </code></pre>
  
  <p>It seems to addAttribute: method works fine. But not display... Why?</p>
  
  <p>Thanks.</p>