Grids Master-Detail Relationship

Hi Everyone,

Sometimes you need to have a screen with 2 grids that depend on each other. When you change line in one grid, it should refresh records in another. In this case you need to establish Grids Master-Detail relationship.

In general master-detail relationship for grids is almost the same as for form-grid. You can read more about it in T200 Framework Fundamentials Training Guide, Example 2.2, Setting Up the Master-Detail Relationship Between Data
As a summary from the training, we need to do 3 points

• Put PXDBDefault attributes in child DAC to auto-initialize dependent keys.
• Put PXParent attribute in child DAC to allow cascade deletion and few other functions.
• Use Current<> parameter in Data Views to refresh child table data based on parent record.

So for grids you need to do the same points,plus some more. I’ll show it based on example of Generic Inquires. We will speak about 2 tables: GIRelation and GIOn that are Master-Detail relationship.

1-Initialize Child Keys

We use PXDBDefault in GIOn DAC to auto-insert keys, so user should not wary about it in UI.

public class GIOn : IBqlTable
{
	public abstract class relationNbr : IBqlField { }
	[PXDBInt(IsKey = true)]
	[PXDBDefault(typeof(GIRelation.lineNbr))]
	public int? RelationNbr { get; set; }
}

2-Specify Parent Record

We also need to use PXParent attribute to enable cascade deletion, formulas, defaulting and some other fictions.

public class GIOn : IBqlTable
{
	public abstract class relationNbr : IBqlField { }
	[PXDBInt(IsKey = true)]
	[PXDBDefault(typeof(GIRelation.lineNbr))]
	[PXParent(typeof(Select<GIRelation,
		Where<GIRelation.designID, Equal<Current<GIOn.designID>>,
		And<GIRelation.lineNbr, Equal<Current<GIOn.relationNbr>>>>>))]
	public int? RelationNbr { get; set; }
}

3-Data View Dependent Select

We also use Current<> parameter in the PXSelect dataview to select proper detailed records. Please note that our child table has 2 conditions as it depends on GIRelation and GIDesign (as primary entity) also.

public class GenericInquiryDesigner : PXGraph<GenericInquiryDesigner, GIDesign>
{
	public PXSelect<GIRelation, Where<GIRelation.designID, Equal<Current<GIDesign.designID>>>> Relations;
	public PXSelect<GIOn, Where<GIOn.designID, Equal<Current<GIDesign.designID>>,
								And<GIOn.relationNbr, Equal<Current<GIRelation.lineNbr>>>>> JoinConditions;
}

4-Grids Auto-Refresh

That is all from the code perspective, but we also need to configure UI to automatically refresh child grid, when we update parent. To do this we enable auto-callback from the parent grid to the child grid. This callback will be triggered on changes in parent and refresh child grid.

<px:PXGrid ID="grdJoins" runat="server" ...>
.....
  <AutoCallBack Command="Refresh" Target="grdOns" ActiveBehavior="True">
    <Behavior RepaintControlsIDs="grdOns" BlockPage="True" CommitChanges="False" ></Behavior>
  </AutoCallBack>
.....
</px:PXGrid>

5-Grids Current Record Sync

And lastly we need to advise Acumatica UI that changes (or selected recird) in the parent grid should be synced back to graph, as dataview there need to know parent for proper child select. To do that we set SyncPosition=”True” for the parent grid.

<px:PXGrid ID="grdJoins" runat="server" SyncPosition="True" ...>
.....
</px:PXGrid>

That is it, now Master-Detail relationship is established and child grid should be refreshed automatically as soon as you change record in the parent grid.

Have a nice development!