How to programmatically scroll and select the records of the multi-level DetailsView on initial loading in UWP DataGrid (SfDataGrid)?

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You can select the records of the Master-DetailsView programmatically on initial loading by setting the corresponding child grid row index to the SfDataGrid.SelectedIndex property. This can be achieved by passing the row index of both the parent and child grids. Before setting the SelectedIndex to child grid, you need to check whether the corresponding parent record is in the expanded or collapsed state. When it is expanded, you can directly select the records of the child grid; otherwise, you need to expand it manually by using the SfDataGrid.ExpandDetailsViewAt helper method. You can also bring the corresponding DetailsView grid into the view by using the DetailsViewManager.BringToView helper method. This is demonstrated in the following code example.

<syncfusion:SfDataGrid x:Name="dataGrid"
                        ColumnSizer="Auto"
                        AutoGenerateColumns="True"
                        AutoGenerateRelations="True"
                        ItemsSource="{Binding Employees}"
                        Loaded="On_DataGrid_Loaded"
                        AutoGeneratingRelations="On_DataGrid_AutoGeneratingRelations">

private void On_DataGrid_AutoGeneratingRelations(object sender, AutoGeneratingRelationsArgs e)
{
    e.GridViewDefinition.DataGrid.AutoGenerateRelations = true;
}
 
private void On_DataGrid_Loaded(object sender, RoutedEventArgs e)
{
    DoSelection();
}
 
private void DoSelection()
{
    var empToSelect = ((ViewModel)this.DataContext).Employees.FirstOrDefault(emp => emp.EmployeeID == 17);
 
    if (empToSelect != null)
    {
 
        this.dataGrid.SelectedItem = empToSelect;
 
        var employeeRowIndex = this.dataGrid.ResolveToRowIndex(this.dataGrid.SelectedIndex);
 
 
        this.ExpandAndSelectDetailsView(this.dataGrid, employeeRowIndex, 22, "Orders");
 
        dataGrid.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
        {
            var orderGrid = dataGrid.GetDetailsViewGrid(this.dataGrid.ResolveToRecordIndex(employeeRowIndex), "Orders");
 
            if (orderGrid != null)
            {
 
                var ordersRowindex = orderGrid.ResolveToRowIndex(orderGrid.SelectedIndex);
 
                this.ExpandAndSelectDetailsView(orderGrid, ordersRowindex, 2, "Sales");
 
 
                dataGrid.SelectionController.GetType().GetMethod("ScrollToRowIndex", System.Reflection.BindingFlags.Instance
                    | System.Reflection.BindingFlags.NonPublic).Invoke(dataGrid.SelectionController, new object[] { dataGrid.SelectionController.CurrentCellManager.CurrentRowColumnIndex.RowIndex });
            }
        });
    }
}
 
private void ExpandAndSelectDetailsView(SfDataGrid dataGrid, int parentRowIndex, int childRowIndex, string relationalColumn)
{
    //Checks whether the given index is parent row index or not. 
    bool IsDetailsViewIndex = dataGrid.IsInDetailsViewIndex(parentRowIndex);
    if (IsDetailsViewIndex == true)
        return;
    //Gets the record of the parent row index.
    var record = dataGrid.View.Records[dataGrid.ResolveToRecordIndex(parentRowIndex)];
    //Gets the DetailsViewManager by using Reflection.
    var propertyInfo = dataGrid.GetType().GetField("DetailsViewManager", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
    DetailsViewManager detailsViewManager = propertyInfo.GetValue(dataGrid) as DetailsViewManager;
    // Checks whether the parent record has the child grid or not by getting the child source and its count.
    var childSource = detailsViewManager.GetChildSource(record.Data, relationalColumn);
    var GetChildSourceCount = detailsViewManager.GetType().GetMethod("GetChildSourceCount", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
    var ChildSourceCount = GetChildSourceCount.Invoke(detailsViewManager, new object[] { childSource });
    if ((int)ChildSourceCount == 0)
        return;
 
    //Checks whether the record is Expanded or Collapsed.
    //When it is in the collapsed state, you need to expand the particular DetailsView based on the index.
    if (!record.IsExpanded) dataGrid.ExpandDetailsViewAt(dataGrid.ResolveToRecordIndex(parentRowIndex));
    //Gets the index of the DetailsView.
    int index = 0;
    foreach (var def in dataGrid.DetailsViewDefinition)
    {
        if (def.RelationalColumn == relationalColumn)
        {
            index = dataGrid.DetailsViewDefinition.IndexOf(def);
            index = parentRowIndex + index + 1;
        }
    }
    //Brings the parent row in the view. 
    var rowcolumnIndex = new RowColumnIndex(index, 1);
    dataGrid.ScrollInView(rowcolumnIndex);
    //Gets the DetailsViewDataGrid by passing the corresponding rowindex and relation name.
    var detailsViewDataGrid = dataGrid.GetDetailsViewGrid(dataGrid.ResolveToRecordIndex(parentRowIndex), relationalColumn);
    //Checks whether the given index is currently in view or not.
    //When the specified index is not currently in view, you can bring that row in to the view by using the SfDataGrid.ScrollInView method.
    var firstline = dataGrid.GetVisualContainer().ScrollRows.GetVisibleLines().FirstOrDefault(line => line.Region == ScrollAxisRegion.Body);
    var lastline = dataGrid.GetVisualContainer().ScrollRows.GetVisibleLines().LastOrDefault(line => line.Region == ScrollAxisRegion.Body);
    if (firstline.LineIndex >= index || lastline.LineIndex <= index)
    {
        //Brings the details view grid in to the view and sets the child grid's SelectedIndex as the ChildRowIndex.
        if (record != null && record.IsExpanded)
        {
            if (detailsViewDataGrid == null)
            {
                detailsViewManager.BringIntoView(index);
                detailsViewDataGrid = dataGrid.GetDetailsViewGrid(dataGrid.ResolveToRecordIndex(parentRowIndex), relationalColumn);
            }
        }
    }
 
    if (detailsViewDataGrid != null)
        detailsViewDataGrid.SelectedIndex = childRowIndex;
}

View Sample in GitHub

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How to programmatically scroll and select the records of the multi-level DetailsView on initial loading in UWP DataGrid (SfDataGrid)?

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