4.1 GGC Rebind

[Administrator]

Hi,
I''m using GGC with TableDescriptors defined through a designer. The datasource of the GGC changes during runtime - it could be a valid DataSet or null. In second case the grid throws an exception:
************************************
Warning: Possible incorrect RelationDescriptor.ChildTableName for Relation RELATION_NAME.
Engine.SourceListSet[SOME_RELATION] returned null.
Did you forget to call Engine.SourceListSet.Add(new SourceListSetEntry(SOME_RELATION, list)
or did you specify a wrong ChildTableName?
Valid ChildTableName entries are:
System.InvalidOperationException: Possible incorrect RelationDescriptor.ChildTableName for Relation DetailPackage.
Engine.SourceListSet[Package] returned null.
Did you forget to call Engine.SourceListSet.Add(new SourceListSetEntry(Package, list)
or did you specify a wrong ChildTableName?
Valid ChildTableName entries are:
at Syncfusion.Grouping.Table.EnsureSourceList()
at Syncfusion.Grouping.Table.EnsureInitialized(Object sender, Boolean notifyParent)
at Syncfusion.Grouping.Element.EnsureInitialized(Object sender)
at Syncfusion.Windows.Forms.Grid.Grouping.GridTableModel.UpdateColumnWidths(Boolean force)
at Syncfusion.Windows.Forms.Grid.Grouping.GridTableModel.UpdateColumnWidths()
at Syncfusion.Windows.Forms.Grid.Grouping.GridTable.VisibleColumns_TotalWidthRequest(Object sender, CancelEventArgs e)
at Syncfusion.Windows.Forms.Grid.Grouping.GridVisibleColumnDescriptorCollection.OnTotalWidthRequest(CancelEventArgs e)
at Syncfusion.Windows.Forms.Grid.Grouping.GridVisibleColumnDescriptorCollection.get_TotalWidth()
at Syncfusion.Windows.Forms.Grid.Grouping.GridTable.GetHorizontalScrollWidth(Boolean isNested)
at Syncfusion.Windows.Forms.Grid.Grouping.GridTable.GetHorizontalScrollWidth(Boolean isNested)
at Syncfusion.Windows.Forms.Grid.Grouping.GridTable.GetHorizontalScrollWidth(Boolean isNested)
at Syncfusion.Windows.Forms.Grid.Grouping.GridTable.GetHorizontalScrollWidth()
at Syncfusion.Windows.Forms.Grid.Grouping.GridTableModel.OnQueryColWidth(GridRowColSizeEventArgs e)
at Syncfusion.Windows.Forms.Grid.GridModel.RaiseQueryColWidth(GridRowColSizeEventArgs e)
at Syncfusion.Windows.Forms.Grid.GridModelColWidthsIndexer.OnQuerySize(GridRowColSizeEventArgs e)
at Syncfusion.Windows.Forms.Grid.GridModelRowColSizeIndexer.GetSize(Int32 index)
at Syncfusion.Windows.Forms.Grid.GridModelRowColSizeIndexer.get_Item(Int32 index)
at Syncfusion.Windows.Forms.Grid.GridControlBase.GetColWidth(Int32 colIndex)
at Syncfusion.Windows.Forms.Grid.GridViewLayout.Initialize()
at Syncfusion.Windows.Forms.Grid.GridViewLayout.DemandInitialize()
at Syncfusion.Windows.Forms.Grid.GridViewLayout.RectangleToClientRowCol(Rectangle rect, Int32& topRow, Int32& leftCol, Int32& bottomRow, Int32& rightCol, GridCellSizeKind sizeKind)
at Syncfusion.Windows.Forms.Grid.GridPaint.DrawGrid(Graphics g, Boolean shouldClip, Rectangle rectClip)
at Syncfusion.Windows.Forms.Grid.GridControlBase.OnPaint(PaintEventArgs pe)
catched at Syncfusion.Windows.Forms.Grid.GridControlBase.OnPaint(PaintEventArgs pe) in :line 0

What would be a correct approach to rebind data during the runtime?
Thank you

[Administrator]

Let me elaborate a little further:

If I call
this.gridGroupingControl1.ResetTableDescriptor();
this.gridGroupingControl1.TableDescriptor.Relations.Reset();
I obviously loose all descriptors, create at design time and do not want to recreate them manually everytime the datasource changes

Thank you

[Administrator]

The solution I found is the following:
1. In the costructor of the host form save GridRelationDescriptorCollection:
col=(GridRelationDescriptorCollection)this.GGC.TableDescriptor.Relations.Clone();
2. Set the DataSource in the following manner:
this.GGC.SuspendLayout();

this.GGC.TableDescriptor.Relations.Reset();

if(ds!=null&&ds.Tables.Count>0&&ds.Tables[0].Rows.Count>0)
{
this.GGC.DataSource=ds.Tables[0];
this.GGC.TableDescriptor.Relations=col;

}
else
{
this.GGC.DataSource=null;
}
this.GGC.ResumeLayout(true);

Is there more efficient ("right") way of doing it?

Thank you

[Administrator]

Hi Ivan,

you could save the whole Engine with all its settings and nested relations using this code:

GridEngine savedEngine = new GridEngine();
savedEngine.InitializeFrom(gridgroupingControl.Engine);

Then you could reset the relations in your control if the datasource is null.

If it is not null you can restore the engine settings with

gridgroupingControl.Engine.InitializeFrom(savedEngine);

The InitializeFrom logic can be used with any descriptors. The way you could also just save a TableDescriptor with nested relations and restore it back at a later time.

Stefan

[Administrator]

This works!
Thank you for the detail explanation.