Combobox in RowDetailTemplate update all before selected colums

Question

I Have a Combobox in a RowdetailsTemplate in a Datagrid. If i switch the columns then automatic change the value in the Datagridcolumn with the before selected Value. The Value in Datagrid column should only change if the value in the Combobox are changed

public class BMFill
{
    public BMFill()
    {
         colCBArt.Add(new CBArt { Name = "test" , Nr = 0 });
        colCBArt.Add(new CBArt { Name = "hallo", Nr = 1 });
        colCBArt.Add(new CBArt { Name = "welt", Nr = 2 });
        colCBArt.Add(new CBArt { Name = "blubb", Nr = 3 });
        colCBArt.Add(new CBArt { Name = "lalalala", Nr = 4 });

    }
    List<CBArt> colCBArt = new List<CBArt>();
    CollectionViewSource cvsCBArt = null;


    public ICollectionView ViewCBArt
    {
        get
        {
            if (cvsCBArt == null) cvsCBArt = new CollectionViewSource() { Source = colCBArt };
            return cvsCBArt.View;
        }
    }


    public class CBArt
    {
        public string Name { get; set; }
        public int Nr { get; set; }
    }
}

<Window.Resources>
    <local:BMFill x:Key="vm"/>
</Window.Resources>
<DataGrid x:Name="dg">
    <DataGrid.RowDetailsTemplate>
        <DataTemplate>
            <ComboBox Margin="10,10,10,10" Grid.Column="1" Grid.Row="1"
                                  SelectedValuePath="Nr"
                                  SelectedValue="{Binding NrDG,UpdateSourceTrigger=PropertyChanged}"
                                  DisplayMemberPath="Name" 
                                  ItemsSource="{Binding Source={StaticResource vm}, Path=ViewCBArt}"
                                  />
        </DataTemplate>
    </DataGrid.RowDetailsTemplate>
</DataGrid>

i hope can understand my problem and can me help =)

score 0 · Answer 1 · answered Apr 25 '17 at 15:19

You can try to add event handlers for DropDownOpened and DropDownClosed events, raise a flag while the dropdown is opened, and check if this flag is not raised while you change the value in the Datagridcolumn.

XAML:

        <ComboBox Margin="10,10,10,10" Grid.Column="1" Grid.Row="1"
                              SelectedValuePath="Nr"
                              SelectedValue="{Binding NrDG,UpdateSourceTrigger=PropertyChanged}"
                              DisplayMemberPath="Name" 
                              ItemsSource="{Binding Source={StaticResource vm}, Path=ViewCBArt}"
                              DropDownOpened="OnDropDownOpened" DropDownClosed="OnDropDownClosed"
                              />

C#:

    private bool _comboxBoxIsOpened = false;
    private void OnDropDownOpened(object sender, EventArgs e)
    {
        _comboxBoxIsOpened = true;
    }

    private void OnDropDownClosed(object sender, EventArgs e)
    {
        _comboxBoxIsOpened = false;
    }

My Problem is i need to update the Datagrid Column if change the value in the combobox — Toni Schönberger, Apr 25 '17 at 16:44
@ToniSchönberger so you can save the previous value on Opened, and check if it changed in Closed (using global variable). If so, update Datagrid Colum — ShugiShugi, Apr 25 '17 at 18:44

score 0 · Accepted Answer · answered Apr 25 '17 at 17:58

SelectedValuePath="Nr"
                                  SelectedValue="{Binding NrDG,UpdateSourceTrigger=PropertyChanged}"
                                  DisplayMemberPath="Name" 
                                  ItemsSource="{Binding Source={StaticResource vm}, Path=ViewCBArt}"
                                  IsSynchronizedWithCurrentItem="False"

this Solution work by me

Combobox in RowDetailTemplate update all before selected colums

2 Answers2