public ProgressBarStateChangedEventArgs(Forms.MyMainMenu.ProgressBarVisibleState _state) : this(_state, null)
 {
 }
 public ProgressBarStateChangedEventArgs(Forms.MyMainMenu.ProgressBarVisibleState _state, object _properties) : base()
 {
     this.ProgressBarState = _state;
     this.Properties       = _properties;
 }