Clearing Nested table in gridGroupingControl

[Prathima Venkobachar]

Hi,

I want to clear nested table structure.Before clearing I need to check whether the grid has child table.How can I do it..?

Thanks,
Prathima

[Administrator]

You can check this value to see if the grid has an hierarchical data source.

bool hasChild = this.gridGroupingControl1.TableDescriptor.Relations != null && this.gridGroupingControl1.TableDescriptor.Relations.Count > 0;
            

[Prathima Venkobachar]

I have a requirenment depending on the user choice(Check checkbox) I should show the nested table information.

I am using the above condition and clearing the nested table column descriptor before binding it to the grid.
First time it works fine i.e when checkbox is not checked.

Next time if I check the checkbox.It works fine.It shows nested table information.

I repeat the same, i.e uncheck and check again
I am getting error.At this point.Columns are cleared.

Also 2nd time when I uncheck, When there are no child reocrds it still displays ''+'' sign.

How can I solve this..?

//Code
if (this.gridGroupingControl.TableDescriptor.Relations != null && this.gridGroupingControl.TableDescriptor.Relations.Count > 0) {
GridEngine engine = this.gridGroupingControl.Engine;
GridTableDescriptor viewTableDescriptor = (GridTableDescriptor) engine.TableDescriptor;
RelationDescriptor ViewHistRelationDescriptor = ViewTableDescriptor.Relations["View_History"];
GridTableDescriptor ViewHistTableDescriptor = (GridTableDescriptor) ViewHistRelationDescriptor.ChildTableDescriptor;
ViewHistTableDescriptor.Columns.Clear();
}

Thanks,
Prathima

[Administrator]

If you do not want to see the nested tables, then one way to do this would be the call this.gridGroupingControl.TableDescriptor.Relations.Clear. Then when you want to see them again, add the relations back. Here is a button handler that either shows or hides nested tables each time you click it.

private void button1_Click(object sender, System.EventArgs e)
{
	if(saveRelations == null)
	{
		saveRelations = new ArrayList();
		foreach(GridRelationDescriptor rd in this.gridGroupingControl1.TableDescriptor.Relations)
			saveRelations.Add(rd);
		this.gridGroupingControl1.TableDescriptor.Relations.Clear();
	}
	else
	{
		foreach(GridRelationDescriptor rd in saveRelations)
			this.gridGroupingControl1.TableDescriptor.Relations.Add(rd);
		saveRelations.Clear();
		saveRelations = null;
	}
}

[Prathima Venkobachar]

Hi,

I tried to save the relation.This is not helping.

My scenario is like this.
I have to show history details in the nested tables.History data is huge.I don''t want to load always and keep in the dataset.
Only when the user selects to view history..I load data to dataset .Otherwise I will have only datatable.

Code looks like this..

//Clear Auto populated Coulmns before binding

GridTableDescriptor tableDescriptor = this.gridGroupingControl.TableDescriptor;
tableDescriptor.Columns.Clear();
tableDescriptor.VisibleColumns.Clear();
tableDescriptor.GroupedColumns.Clear();
foreach(GridSummaryRowDescriptor rd in sfgAssetView.TableDescriptor.SummaryRows)
rd.SummaryColumns.Clear();
tableDescriptor.SummaryRows.Clear();
tableDescriptor.SortedColumns.Clear();
tableDescriptor.ExpressionFields.Clear();
tableDescriptor.ResetSummaries();

if (this.gridGroupingControl.TableDescriptor.Relations != null && this.gridGroupingControl.TableDescriptor.Relations.Count > 0) {
GridEngine engine = this.gridGroupingControl.Engine;
GridTableDescriptor viewTableDescriptor = (GridTableDescriptor) engine.TableDescriptor;
RelationDescriptor ViewHistRelationDescriptor = ViewTableDescriptor.Relations["View_History"];
GridTableDescriptor ViewHistTableDescriptor = (GridTableDescriptor) ViewHistRelationDescriptor.ChildTableDescriptor;
ViewHistTableDescriptor.Columns.Clear();
}

//Bind datatable/dataset to the grid

dataSet = new DataSet("ViewHistDet");
if (ShowHistory) {
if (this.SrcDataSet != null) {
DataTable dtHistoryDetails = GetTable("HISTORY_DETAILS");
dtHistoryDetails.TableName = "AWB_HISTORY_DETAILS_NESTED";
DataTable dtHist = dtHistoryDetails.Copy();
DataTable dt = this.dataTable.Copy();
dt.TableName = "AssetView";
if (!dataSet.Tables.Contains(dt.TableName)) {
dataSet.Tables.Add(dt);
}

if (!dataSet.Tables.Contains(dtHist.TableName)) {
dataSet.Tables.Add(dtHist);
}
}

dataSet.Relations.Add(dataSet.Tables[0].Columns["Id"],
dataSet.Tables[1].Columns["Id"]);
dataSet.Relations[0].RelationName = "View_History";
this.gridGroupingControl.DataSource = dataSet.Tables[0];

}else {
this.gridGroupingControl.DataSource = this.dataTable;

}

//Set Styles to Nested table

if (showHistory) {
GridEngine engine = this.gridGroupingControl.Engine;
engine.ChildGroupOptions.ShowCaption = true;
engine.NestedTableGroupOptions.ShowColumnHeaders = false;
engine.NestedTableGroupOptions.ShowGroupHeader = false;
engine.NestedTableGroupOptions.ShowCaption = false;
engine.NestedTableGroupOptions.ShowCaptionPlusMinus = false;
engine.NestedTableGroupOptions.ShowEmptyGroups = false;
GridTableDescriptor ViewTableDescriptor = (GridTableDescriptor) engine.TableDescriptor;
RelationDescriptor ViewHistRelationDescriptor = ViewTableDescriptor.Relations["View_History"];
GridTableDescriptor ViewHistTableDescriptor = (GridTableDescriptor) ViewHistRelationDescriptor.ChildTableDescriptor;
ViewTableDescriptor.Appearance.AnyHeaderCell.Borders.All = new GridBorder(GridBorderStyle.None);
ViewHistTableDescriptor.AllowNew = false;
ViewHistTableDescriptor.AllowEdit = false;
ViewHistTableDescriptor.Appearance.AnyNestedTableCell.Borders.All = new GridBorder(GridBorderStyle.None);
ViewHistTableDescriptor.Appearance.AnyRecordFieldCell = ViewHistStyle;
ViewHistTableDescriptor.Columns[0].Width = 75; // - Here I get a error - "Object reference not set to an instance" -
ViewHistTableDescriptor.Columns[1].Width = 40; // Sometimes cast not valid or out of range.At this point the tabledescriptor
ViewHistTableDescriptor.Columns[2].Width = 55; // is cleared.
ViewHistTableDescriptor.Columns[3].Width = 55;
ViewHistTableDescriptor.Columns[4].Width = 55;
ViewHistTableDescriptor.Columns[5].Width = 55;
ViewHistTableDescriptor.Columns[6].Width = 55;
ViewHistTableDescriptor.Columns[0].Appearance.AnyRecordFieldCell = ViewHistDateStyle;
ViewHistTableDescriptor.Columns[2].Appearance.AnyRecordFieldCell = ThreeDecimalStyle;
ViewHistTableDescriptor.Columns[3].Appearance.AnyRecordFieldCell = ThreeDecimalStyle;
}

this.gridGroupingControl.TableDescriptor.Columns.LoadDefault();

// Apply styles to Parent table..

Everytime before binding I set relation to the dataset..
I tried saving and setting relation to the gridGroupingControl.tablesdescriptor...but this not working..

Thanks,
Prathima

[Administrator]

Can you upload a sample project showing what you are tring to do so we can run it here?