Ok, I figured it out after a lot of searching.
but it seems that you are just doing the same for ElementStyle, again with the target type of the combo box, even if it does not show ComboBox when it is not being edited.
<DataGridComboBoxColumn Header="Formatter" SelectedItemBinding="{Binding Path=Format}"> <DataGridComboBoxColumn.ElementStyle> <Style TargetType="ComboBox"> <Setter Property="ItemsSource" Value="{Binding Path=DefinedFormatters}" /> <Setter Property="IsDropDownOpen" Value="True" /> <Setter Property="ItemTemplate"> <Setter.Value> <DataTemplate> <TextBlock Text="{Binding Path=Name}"></TextBlock> </DataTemplate> </Setter.Value> </Setter> </Style> </DataGridComboBoxColumn.ElementStyle> <DataGridComboBoxColumn.EditingElementStyle> <Style TargetType="ComboBox"> <Setter Property="ItemsSource" Value="{Binding Path=DefinedFormatters}" /> <Setter Property="IsDropDownOpen" Value="True" /> <Setter Property="ItemTemplate"> <Setter.Value> <DataTemplate> <TextBlock Text="{Binding Path=Name}"></TextBlock> </DataTemplate> </Setter.Value> </Setter> </Style> </DataGridComboBoxColumn.EditingElementStyle> </DataGridComboBoxColumn>
source share