Initializing data on AddingNewDataItem

[Steve]

Hello

I'm trying to set default values for a DataRow when it is newly inserted into a RadGridView. See the cut down sample below.
If I use AddingNewDataItem to create the row, then I get an error.
If instead I let the grid create the row, and then use BeginningEdit to set the values, then the values don't show.

What's the best way to set default values with a new DataRow?

Many Thanks



public partial class MainWindow : Window

{

       private RadGridView _grid;

       private DataTable _table;

 

       public MainWindow()

       {

              InitializeComponent();

 

              _grid = new RadGridView { AutoGenerateColumns = false, CanUserInsertRows = true, ShowInsertRow = true };

              Content = _grid;

      

              _grid.AddingNewDataItem += new EventHandler<GridViewAddingNewEventArgs>( _grid_AddingNewDataItem );

              _grid.BeginningEdit += new EventHandler<GridViewBeginningEditRoutedEventArgs>( _grid_BeginningEdit );

 

              _grid.Columns.Add( new GridViewDataColumn { DataMemberBinding = new Binding { Path = new PropertyPath( "Column1" ), Mode = BindingMode.TwoWay } } );

              _grid.Columns.Add( new GridViewDataColumn { DataMemberBinding = new Binding { Path = new PropertyPath( "Column2" ), Mode = BindingMode.TwoWay } } );

 

              _table = new DataTable();

              _table.Columns.Add( "Column1", typeof( string ) );

              _table.Columns.Add( "Column2", typeof( string ) );

              _table.Rows.Add( "row1-col1", "row1-col2" );

              _grid.ItemsSource = _table.DefaultView;

       }

 

       private void _grid_BeginningEdit( object sender, GridViewBeginningEditRoutedEventArgs e )

       {

              // This won't show "INIT" until Column2 is focused

              //DataRowView dataRowView = e.Row.Item as DataRowView;

              //if( dataRowView.Row.RowState == DataRowState.Detached )

              //{

              //    dataRowView[ "Column2" ] = "INIT";

              //}

       }

 

       private void _grid_AddingNewDataItem( object sender, GridViewAddingNewEventArgs e )

       {

              // This will cause an error: Cannot add external objects to this list

              //e.NewObject = _table.DefaultView.AddNew();

       }

}

[Vanya Pavlova]

Hi Steve,

 
You may use the following forum thread for further reference.

All the best,
Vanya Pavlova
the Telerik team

[Steve]

Thanks for the reply Vanya.  I couldn't find anywhere in the attached code on that thread where a new data record is initialized prior to showing though.

I'm basically trying to do:

TheNewDataRow[ "Column1" ] = "some data"

before showing the new record.

Many Thanks

[Nedyalko Nikolov]

Hello Steve,

Generally AddingNewDataItem event is the right way to achieve this task. With the specific of the DataTable.DefaultView and that its AddNew method used to create a new DataRowView actually adds this row into table. This sounds great by DefaultView implements INotifyCollectionChanged and this item is inserted immediately in RadGridView, so we have to cancel adding new row from RadGridView again. This could be accomplished by e.Cancel = true within AddingNewDataItem event handler. Another part of the task is to put this particular row into edit mode. This could be done by RadGridView.ScrollIntoViewAsync method. I hope that following code snippet will be helpful.

void radGridView_AddingNewDataItem(object sender, GridViewAddingNewEventArgs e)
        {
            e.Cancel = true;
            var newRow = this.dataSource.DefaultView.AddNew();
            newRow["FirstName"] = "John";
            newRow["LastName"] = "Doe";
            this.radGridView.ScrollIntoViewAsync(newRow, (f) =>
            {
                GridViewRow row = f as GridViewRow;
                if (row != null)
                {
                    ((GridViewCell) row.Cells[0]).BeginEdit();
                }
            });
        }

Let me know how it works on your end.

Regards,
Nedyalko Nikolov
the Telerik team

[Steve]

Perfect, that works well. Thanks Nedyalko.