title: Use MBProgressHUD only disable the navigationItems but not the tab bar
body: <p>I use the following code and want to disable  the navigationItems but make the tab bar still enable,but it doesn't work. both the navigation items and tab bar disable while loading data.</p>
  
  <pre><code>    HUD = [[MBProgressHUD alloc] initWithView:self.tabBarController.view];
      [self.tabBarController.view addSubview:HUD];
      HUD.labelText = NSLocalizedString(@"Loading...", nil) ;
      [HUD show:YES];
  </code></pre>
  
  <p>I don't know make which to be the <code>HUD</code>'s parent view it should work.</p>