code: function (newFocus) {
                      var targetItem;
                      switch (newFocus.type) {
                          case _UI.ObjectType.item:
                              targetItem = this._view.items.itemAt(newFocus.index);
                              this._updateFocusCache(newFocus.index);
                              break;
                          case _UI.ObjectType.groupHeader:
                              this._lastFocusedElementInGroupTrack = newFocus;
                              var group = this._groups.group(newFocus.index);
                              targetItem = group && group.header;
                              break;
                          case _UI.ObjectType.header:
                              this._lastFocusedElementInGroupTrack = newFocus;
                              targetItem = this._header;
                              break;
                          case _UI.ObjectType.footer:
                              this._lastFocusedElementInGroupTrack = newFocus;
                              targetItem = this._footer;
                              break;
                      }
                      this._unsetFocusOnItem(!!targetItem);
                      this._selection._setFocused(newFocus);
                      this._setFocusOnItem(newFocus);
                  }
docs: Updates ListView's internal focus state and, if ListView currently has focus, moves Trident's focus to the item at index newFocus. Similar to _changeFocus except _changeFocusPassively doesn't: - ensure the item is selected or visible - set Trident's focus to newFocus when ListView doesn't have focus