title: UITextField First responder, minimizing app and then restoring, cursor looks and text disappears during typing
body: <p>in my viewDidLoad I have this:</p>
  
  <pre><code>- (void)viewWillAppear:(BOOL)animated {
  
      [super viewWillAppear:animated];
      self.activityIndicator.hidden=YES;
  
  
      [self.userField becomeFirstResponder];
  
  }
  </code></pre>
  
  <p>If the cursor is in the userField and I minimize the app and then restore it it behaves odd, the text content of the field disappears as I type. Is there anyway to fix this? Do I have to resign the first responder before the app is minimised or something? Thanks</p>