title: Add a click event to some text in ios NSString
body: <p>I have the following code and want to make parts of my text be clickable and call another UIViewController (not a website).</p>
  
  <pre><code>NSMutableAttributedString *str = [[NSMutableAttributedString alloc] initWithString:@"testing it out @clickhere"];
  NSInteger length = str.length;
  [str addAttribute:NSForegroundColorAttributeName value:[UIColor bestTextColor] range:NSMakeRange(0,length)];
  </code></pre>
  
  <p>The NSMutableAttributedString gets set to a UILabel like so:</p>
  
  <pre><code>label.attributedText = str;
  </code></pre>
  
  <p>Whats the best way to do this? I can't seem to find a great answer.</p>
  
  <p>An example of what I want is suppose I have a UILabel like so with the following text:</p>
  
  <pre><code>This is my label.  Click here to go to UIViewController1 and then go to UIViewController1 by this #tag.
  </code></pre>
  
  <p>I want the text "here" to be passed for the first click event and the word "#tag" to be passed to the same click event.</p>