code: function tryFocusingCurrentView() {
              if (self._currentView) {
                  if (self._currentView.focus) {
                      //  Views can implement a focus
                      //  method for focusing a complex
                      //  DOM like codemirror
                      self._currentView.focus();
                  } else {
                      //  Otherwise, no focus method
                      //  just try and give the DOM
                      //  element focus
                      self._currentView.$el.focus();
                  }
              } else {
                  // no view so just focus the pane
                  self.$el.focus();
              }
          }
docs: Helper to focus the current view if it can