dev gridview 設置分組

private void GridConfig()
{
GridGroupSummaryItem item = new GridGroupSummaryItem();
item.FieldName = "group_type";
item.SummaryType = DevExpress.Data.SummaryItemType.Count;
gridView1.GroupSummary.Add(item);
gridView1.Columns["app_type"].GroupIndex = 0;
gridView1.Columns["id"].Width = 70;
}