Removing the Drilldown Plus Icon (+) from XtraGrid GridView's MasterRow when ChildRow Has No Data

Question

This is related to a DevExpess XtraGrid's GridView.

I need to remove the drilldown plus icon (+) from any MasterRow in a GridView that doesn't have any data for it's ChildRow.

Currently, all the rows (MasterRows) in my GridView display the drilldown plus icon (+). When the drilldown plus icon (+) is clicked, the ChildRow is displayed with the appropriate data. But, if the ChildRow has no data, then the ChildRow is not displayed (expanded). I need to make the drilldown plus icon (+) invisible so that the user doesn't see it if there is no data in the ChildRow.

I have a function that checks if data is available for the ChildRow, which then allows the ChildRow to display (expand) or not.

I have used GridView.OptionsView.ShowDetailButtons but that hides the drilldown plus icons (+) on all the rows. That doesn't work for me since I only need to hide it if there is no data for the ChildRow.

Here is the code that I have so far:

private void gridView1_MasterRowGetRelationCount(object sender, MasterRowGetRelationCountEventArgs e)
{
    e.RelationCount = 1;
}

private void gridView1_MasterRowEmpty(object sender, MasterRowEmptyEventArgs e)
{
    e.IsEmpty = IsRelationEmpty(e.RowHandle, e.RelationIndex);
}

bool IsRelationEmpty(int rowHandleX, int relationIndex)
{
    Tuple<string, double, double> row = (Tuple<string, double, double>)gridView1.GetRow(rowHandleX);
    return rowHandleX == DevExpress.XtraGrid.GridControl.InvalidRowHandle || _tfs._dataDictionary[row.Item1.ToString()].Item2.Count == 0;
}

private void gridView1_MasterRowGetChildList(object sender, MasterRowGetChildListEventArgs e)
{
    if (IsRelationEmpty(e.RowHandle, e.RelationIndex))
    {
        return;
    }

    Tuple<string, double, double> row = (Tuple<string, double, double>)gridView1.GetRow(e.RowHandle);
    e.ChildList = _tfs._dataDictionary[row.Item1.ToString()].Item2.ToList(); // _tfs.DictionaryToList();
}

private void gridView1_MasterRowGetRelationName(object sender, MasterRowGetRelationNameEventArgs e)
{
    e.RelationName = "Work Items with no Size Estimate:";
}

Any direction or suggestions would be greatly appreciated.

Thanks in advance,

Marwan (^_^)

Answer 1

I suggest you to follow this DevExpress thread - How to hide disabled expand/collapse buttons for master rows without detail records

The XtraGrid does not provide an option to hide master-detail expand buttons for empty details. You can work around this limitation via the CustomDrawCell event.

Here is the necessary code:

private void gridView1_CustomDrawCell(object sender, DevExpress.XtraGrid.Views.Base.RowCellCustomDrawEventArgs e) {

    GridView view = sender as GridView;
    if(e.Column.VisibleIndex == 0 && view.IsMasterRowEmpty(e.RowHandle))
        (e.Cell as GridCellInfo).CellButtonRect = Rectangle.Empty;
    }
}

Hope this help..