UI Representation of User-Defined Object

In the SAP UI context, we aim to create a model to manage the following aspects of a Form’s events:

• Business logic
• User Data Sources
• Tab handling
• ItemEvents
• Right-click menu events
• Data events

To efficiently manage UI interactions with a UDO, this guide explains how to build a UI model on top of a UDO entity.

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Basic Setup

Creating a UI model on top of the business logic UDO bean links the SAP UI form with its events, facilitating a framework for:

• MVVM-like behavior

For event handling, you can retrieve data from the form as follows:

Example: Getting UDO from Form

public override void OnMatrixLoadBefore(string formUid, ref PItemEvent itemEvent)

Example: Modifying UDO Values

private void HandleInvoiceCFL(PItemEvent itemEvent)
{
    DataTable dt = itemEvent.CFL_Event.SelectedObjects;
    LoadFromToAction(itemEvent.CurrentForm, udo =>
    {
        if (dt.Rows.Count == 0)
        {
            // Clear the fields
            udo.U_InvNr = 0;
            udo.SetSellerInvNumber("");
        }
        else
        {
            var tool = _coreConnection.GetService<IVehicleMasterDataUiTools>();
            udo.U_InvNr = dt.GetInt("DocEntry", 0);
            udo.SetSellerInvNumber(tool.GetSellerInvoiceNr(udo.U_InvNr));
        }
    });
}

Example: Filling User Data Sources

LoadFromToAction(itemEvent.CurrentForm, udo =>
{
    udo.SetSellerCardName("Filled From Code");
    udo.SetSellerInvNumber("");
});

Setting Up Objects

Define your main UI class to link with the appropriate UDO entity, allowing support for multiple forms per UDO code.

public partial class VehicleMasterDataUI : BaseUIBeanLoader<IVehicleMasterData>

This links the VehicleMasterDataUI UI model with the IVehicleMasterData UDO.

Example: Defining User Data Sources (UDS)

Define UDS to facilitate form interactions, linking data between the form and UDO entity (either the header or a child table).

[GenerateUiUdoDefinition(To = typeof(VehicleMasterDataUI), For = "", FormTypeEx = VehicleMasterDataForm.FormTypeEx)]
public partial class VehicleMasterDataUiHeaderUserDataSources
{
    [UDS(UdsType = typeof(string), UdsUniqueId = "CardName")]
    public const string SellerCardName = "SellerCardName";
    
    [UDS(UdsType = typeof(string), UdsUniqueId = "InvDocNum")]
    public const string SellerInvNumber = "SellerInvNumber";
}

Using Computec.SourceGenerator analyzer, you can generate the necessary extension methods, which can then be utilized in your UI model.

GetDefinitions Method

The GetDefinitions method returns the generated model description. It allows setting up tabs, data sources, matrices, menus, and other UI logic.

protected override UserInterfaceUdoDefinitions GetDefinitions()
{
    var definitions = getGeneratedDefinitions();
    definitions
        .ForForm(VehicleMasterDataForm.FormTypeEx)
        .SetTabs(
            TabDef(VehicleMasterDataForm.Controls.DetailsTab, 1),
            TabDef(VehicleMasterDataForm.Controls.OwnersTab, 2, VehicleMasterDataForm.Controls.OnwersMatrix)
        );
    
    return definitions;
}

Loading User Data Sources into the UDO

When a user opens a form with a specific record, you may want to refresh UDS values in the model. Override FillAllUserDataSource to manage this, adding any custom logic that should execute each time the data is loaded.

protected override void FillAllUserDataSource(IVehicleMasterData bean, Form frm)
{
    var tool = _CoreConnection.GetService<IVehicleMasterDataUiTools>();
    bean.SetSellerCardName(!string.IsNullOrEmpty(bean.U_BuyBy) ? tool.GetSellerName(bean.U_BuyBy) : "");
    bean.SetSellerInvNumber(bean.U_InvNr != 0 ? tool.GetSellerInvoiceNr(bean.U_InvNr) : "");
}

Advanced Scenarios

Additional methods can be overridden as needed:

• BeforeLoadToForm: Custom logic before loading data to form
• AfterLoadToForm: Custom logic after loading data to form

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This guide outlines the foundational concepts and advanced practices for integrating UDOs with SAP UI, ensuring efficient and maintainable implementations. With the steps detailed above, developers can achieve seamless interaction between forms and underlying UDO entities.