Question

I have a wpf datagrid with 2 columns (ProductID and Description). ProductID column is a combobox and the Description is a Textbox. On the SelectionChanged event of the ProductID, I want to assign a value to the Description column. I need to know how to assign the value to the Description textbox for the row of the combobox that fired the SelectionChanged event. Can someone please provide a sample code? This seems so simple but I can’t find an answer. Thanks

Answer 1

A better way to do this is by using Binding to Properties like

private ProductIdEnum m_productId;
public ProductIdEnum ProductId
{
    get
    {
        return m_productId;
    }
    set
    {
        m_productId = value;
        // Value changed...
    }
}

To add an EventHandler for the SelectionChanged event of the ComboBox you could do this but I wouldn’t recommend it.

<DataGridComboBoxColumn Header="ProductID"
                        ...">
    <DataGridComboBoxColumn.EditingElementStyle>
        <Style TargetType="{x:Type ComboBox}">
            <EventSetter Event="SelectionChanged" Handler="ProductIdChanged" />
        </Style>
    </DataGridComboBoxColumn.EditingElementStyle>
</DataGridComboBoxColumn>

And in code behind

public T GetVisualParent<T>(object childObject) where T : Visual
{
    DependencyObject child = childObject as DependencyObject;
    while ((child != null) && !(child is T))
    {
        child = VisualTreeHelper.GetParent(child);
    }
    return child as T;
}

void ProductIdChanged(object sender, SelectionChangedEventArgs e)
{
    ComboBox comboBox = sender as ComboBox;
    DataGridRow dataGridRow = GetVisualParent<DataGridRow>(comboBox);
    SomeClass myClass = dataGridRow.Item as SomeClass;
    // Set description
}