Set this option to true to enable grouping using the context menu. In this case, to group/ungroup data, the user right-clicks a column header and chooses the required item from the appeared context menu.
By default, to expand/collapse a group, the user clicks its expand/collapse button. On small-screen devices, this approach may impair the user experience. As an alternative, consider expanding/collapsing a group by a click on the group row. For this purpose, assign "rowClick" to the grouping.expandMode option.
GridGroupingExpandMode enum to specify this option when the widget is used as an ASP.NET MVC 5 Control or a DevExtreme-Based ASP.NET Core Control. This enum accepts the following values:
Use the options of this object to localize or customize grouping-related elements. For example, the groupByThisColumn, ungroup and ungroupAll options customize items of the context menu. These items appear in the menu only if the grouping.contextMenuEnabled option is set to true.