Package com.smartgwt.client.widgets.grid.events

# Interface HasGroupByHandlers

All Superinterfaces:
  `HasHandlers`

All Known Implementing Classes:
  `CalendarView`, `CubeGrid`, `DateGrid`, `EditTree`, `ListGrid`, `ListPalette`, `Menu`, `MenuPalette`, `PickListMenu`, `RecordEditor`, `SelectionTreeMenu`, `TableView`, `TreeGrid`, `TreePalette`

public interface HasGroupByHandlers extends HasHandlers

- ## Method Summary

  Modifier and Type
  Method
  Description
  `HandlerRegistration`
  `addGroupByHandler(GroupByHandler handler)`
  Callback fired when the user attempts to group or ungroup the listGrid, or when `groupBy()` is called programmatically.

  ### Methods inherited from interface com.google.gwt.event.shared.HasHandlers

  `fireEvent`

- ## Method Details

  - ### addGroupByHandler

    HandlerRegistration addGroupByHandler(GroupByHandler handler)
    Callback fired when the user attempts to group or ungroup the listGrid, or when `groupBy()` is called programmatically. This event may be cancelled.

    This notification is fired before the `data` is updated to reflect the grouping. See also `ListGrid.groupByComplete()`.

    Note that this method is not called when the data is regrouped, either `programmatically`, or in response to new data arriving from the server, and such regrouping can't be canceled - instead use callback `ListGrid.regroup()`.

    Parameters:
      `handler` - the groupBy handler
    Returns:
      `HandlerRegistration` used to remove this handler