title: Use of MBProgressHUD Globally + make it singleton
body: <p>In my Project, each of the user interaction events make a network call (Which is TCP, not HTTP). I need Activity Indicator to be global to <strong>show</strong> from a random <code>UIViewController</code> and  <strong>hide</strong> from <code>NetworkActivityManager</code> Class (a custom class to handle network activities, Which is not a subclass of UIViewController or UIView).</p>
  <p>After searching the web I found out that <strong>MBProgressHUD</strong> is used for the same purpose, but I wasn't able to find out an example on how would I use it globally. (By saying global I mean a singleton object of <strong>MBProgressHUD</strong> and class methods to SHOW and HIDE it.)</p>
  <p>Following is what I have tried yet, but, failed:
  In <strong>AppDelegate.h:</strong></p>
  <p><code>@property (nonatomic, retain) MBProgressHUD *hud;</code></p>
  <p>In <strong>AppDelegate.m:</strong></p>
  <p><code>@synthesize hud;</code></p>
  <p>In some random UIViewController object:</p>
  <pre><code>appDelegate.hud = [MBProgressHUD showHUDAddedTo:appDelegate.navigationController.topViewController.view animated:YES];
  appDelegate.hud.labelText = @&quot;This will take some time.&quot;;
  </code></pre>
  <p>And while hiding it, from <code>NetworkActivityManager</code> Class:</p>
  <pre><code>[MBProgressHUD hideHUDForView:appDelegate.navigationController.topViewController.view animated:YES];
  </code></pre>
  <p>This makes the project to crash after some time (due to memory issues.)
  I am using ARC in my project and also, I am using the ARC version of <strong>MBProgressHUD</strong>.</p>
  <p>Am I missing something?</p>
  <p><strong>Important Question:</strong></p>
  <p>Can I make <strong>MBProgressHUD</strong> work like UIAlertView? (Saying that I mean implementation of <strong>MBProgressHUD</strong> independent of UIView -- sa it uses <code>showHUDAddedTo:</code> to present itself) ???</p>
  <p>Please Note: In the above code of hiding MBProgressHUD, View may be changed from what it was when showing MBProgressHUD.</p>
  <p>Any Help greatly appreciated.</p>