Adding a push button to the "Summary" Header

[David Llewellyn]

Hello,

Is there any way in which I can add a "push button" to the right hand side of the summary headers on a grouping grid. I want to be able to use this button to select all checkboxes in a certain column, for that particular group.

I can change the whole header into a large button, by the following code:-

private void TableControl_PrepareViewStyleInfo(object sender, GridPrepareViewStyleInfoEventArgs e)
{
if(e.Style.CellType == "Header")
{
string formtext = e.Style.FormattedText.ToString();
e.Style.CellType = "PushButton";
e.Style.Description = formtext;
}

This makes the header into a large button with the description. But I would like a small button placed on the right hand side of the summary in the header row.

Thanks,
David.

[Administrator]

David,

You could handle TableModel.QueryCoveredRange. The GridTable class internally handles QueryCoveredRange
and executes the code below for DisplayElementKind.Caption:

		protected virtual void OnQueryCoveredRange(GridQueryCoveredRangeEventArgs e)
		{
			GridTable thisTable = this;
			if (e.RowIndex < thisTable.DisplayElements.Count)
			{
				Element el = thisTable.DisplayElements[e.RowIndex];

				switch (el.Kind)
				{
					case DisplayElementKind.Caption:
					{
						int maxCaptionColCount = Math.Max(this.GetColumnIndentCount(), TableDescriptor.GetColCount()-1);
						int startCol = el.GroupLevel+1;
						IGridGroupOptionsSource g = el.ParentGroup as IGridGroupOptionsSource;
						if (g != null && !g.GroupOptions.ShowCaptionPlusMinus)
						{
							startCol--;
						}
						int d = (RelatedTables.Count > 0) ? 1 : 0;
						if (!((GridTable) el.ParentTable).TableOptions.ShowRecordPlusMinus)
							d = 0;
						if (e.ColIndex >= startCol && e.ColIndex <= maxCaptionColCount)
						{
							if (g == null || !g.GroupOptions.ShowCaptionSummaryCells)
							{
								e.Range = GridRangeInfo.Cells(e.RowIndex, startCol, e.RowIndex, maxCaptionColCount);
								e.Handled = true;
							}
							else
							{
								e.Range = GridRangeInfo.Cell(e.RowIndex, e.ColIndex);
								if (e.Range.Left <= GetColumnIndentCount())
								{
									e.Range = e.Range.UnionRange(GridRangeInfo.Cells(e.Range.Top, el.GroupLevel+1+d, e.Range.Bottom, GetColumnIndentCount()));
									e.Handled = true;
								}
							}
						}
						else if (e.ColIndex == el.GroupLevel)
						{
							e.Range = GridRangeInfo.Cell(e.RowIndex, e.ColIndex);
							e.Handled = true; // PlusMinus
						}
						else if (e.ColIndex > maxCaptionColCount)
						{
							e.Range = GridRangeInfo.Cell(e.RowIndex, e.ColIndex);
							e.Handled = true;
						}
						break;
					}
				}
			]
		}

So, what you could do is provide your own handler for QueryCoveredRange - copy paste above code into your handler
and modify it to your needs.

make sure to set e.Handled = true. This will instruct the grid not to exececute it''s own (above) covering mechanism
for the DisplayElementKind.Caption

Stefan

[Administrator]

Or maybe better would be to create your own cell type, derive it from GridHeaderCellRenderer/GridHeaderCellModel and register it with groupingControl.TableModel, e.g. as "MyCaption" cell type.

Then you can assign that celltype to
groupingControl.Appearance.GroupCaptionCell.CellType = "MyCaption".

In your derived cell type you can add a button (as shown in the Grid\Samples\In Depth\CellButtons example) or simply override OnDraw and do your own custom drawing for the caption cell.

Stefan

[David Llewellyn]

Hello Stefan.

Thank you for your help. I have created a new gridcellbutton as you have suggested and it now looks good.

Although, now I need to know what groupsummary header button has been clicked on. I am using a objectgrid_TableControlCellButtonClicked event, but how do I retrieve the summary data?

For example, if the summary header is:
Collection ID : Cars - 21 Items

How do I interrogate this and retrieve this data? I need to be able to find the string "Cars".

[David Llewellyn]

Hello Stefan,

Please ignore the last message that I posted. I realise that I could use this code on the event click to obtain the summary caption string:-

Element el = this.objectgrid.Table.DisplayElements[e.Inner.RowIndex];
string captionsummary = el.Info.ToString();

Thanks for your help.
David

[Administrator]

David,

don''t rely on the Info property - this is more for help with debugging to find out what kind of object you are dealing with ...

Better do this:

Group g = this.objectgrid.Table.DisplayElements[e.Inner.RowIndex].ParentGroup;
string captionsummary = g.Category; // or CategoriesToString();

or

GridTableCellStyleInfo style = this.objectgrid.TableModel[e.Inner.RowIndex, e.Inner.ColIndex];
Group g = style.TableCellIdentity.DisplayElement.ParentGroup;
...

Stefan

[David Llewellyn]

Hello Stefan,

That works well. Thanks for your help.

David.