title: Can't hide the keyboard with shouldChangeCharactersInRange
body: <p>This is my code:</p>
  
  <pre><code>- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string 
  {
      NSCharacterSet *nonNumberSet = [[NSCharacterSet characterSetWithCharactersInString:@"אבגדהוזחטיכלמנסעפצקרשתףץםן"] invertedSet];
  
      // max charcters
      NSUInteger newLength = [textField.text length] + [string length] - range.length;
      if (newLength &gt; 14)
          return NO;
  
      // allow backspace
      if (range.length &gt; 0 &amp;&amp; [string length] == 0) {
          return YES;
      }
      // do not allow . at the beggining
      if (range.location == 0 &amp;&amp; [string isEqualToString:@"."]) {
          return NO;
      }
      if ((range.location &gt; 0) &amp;&amp; (([[textField.text substringWithRange:NSMakeRange((range.location -1), 1)] isEqualToString:@"ף"]) || ([[textField.text substringWithRange:NSMakeRange((range.location -1), 1)] isEqualToString:@"ץ"]) || ([[textField.text substringWithRange:NSMakeRange((range.location -1), 1)] isEqualToString:@"ם"]) || ([[textField.text substringWithRange:NSMakeRange((range.location -1), 1)] isEqualToString:@"ן"])))   
      {
          return NO;
      }
  
      // set the text field value manually
      NSString *newValue = [[textField text] stringByReplacingCharactersInRange:range withString:string];
      newValue = [[newValue componentsSeparatedByCharactersInSet:nonNumberSet] componentsJoinedByString:@""];
      textField.text = newValue;
      // return NO because we're manually setting the value
      return NO;
  }
  </code></pre>
  
  <p>I just want to do when you click on <kbd>Return</kbd> the keyboard will disappear. I can't do that. where to add it and how?</p>