public static bool IsBusy {get;}

{
  // The application is considered busy if a task is currently running on the main worker thread or any 
  // pane or dock pane reports that it is busy or initializing.   

  // Many Pro styles (such as Esri_SimpleButton) ensure that a button is disabled when FrameworkApplication.IsBusy is true
  // You would use this property to bind to the IsEnabled property of a control (such as a listbox) on a dockpane or pane in order
  // to disable it from user interaction while the application is busy. 

  bool isbusy = FrameworkApplication.IsBusy;
}