How to bind the same collection of values into all ComboBoxes in a DataGridComboBox?

Question

I have a Collection of Values in an Array of Strings, or in a List or whatever, and what i want is to set this Collection of values as the Collection of items into all the ComboBoxes in a column as DataGridComboBoxColumn in WPF.

I think i don't have other way to access this Collection of Values and bind it equally to all the ComboBoxes (in XAML) beside the DataContext. But can i access the DataContext of a DataGrid from a DatGridComboBoxColumn (in XAML)? Can i do it? How?

How i specify (in XAML) in DatagridComboBoxColumn to put this Collection of Items equally in all ComboBoxes? How i can achieve this?

Here is my XAML:

(...)xmlns:local="clr-namespace:WpfApp"(...)

<Grid Name="grid1">
    <DataGrid Name="dataGrid" AutoGenerateColumns="True">
        <DataGrid.Columns>
            <DataGridComboBoxColumn Header="Options" Width="100"/>
        </DataGrid.Columns>
    </DataGrid>
</Grid>

And here is my Code Behind:

public class TestClass
{
    private static string[] stringArray = { "Option One", "Option Two", "Option Three" };

    public static string[] StringArray
    {
        get
        {
            return stringArray;
        }
    }
}

Answer 1

But can i access the DataContext of a DataGrid from a DatGridComboBox Column (in XAML)? Can i do it? How?

There's no straightforward way to access the DataContext of the DataGrid from the column definition, because it isn't part of the visual or logical tree, so it doesn't inherit the DataContext. I recently blogged about a solution to that issue. Basically you need to do something like that:

<DataGrid Name="dataGrid" AutoGenerateColumns="True">
    <DataGrid.Resources>
        <!-- Proxy for the current DataContext -->
        <local:BindingProxy x:Key="proxy" Data="{Binding"} />
    </DataGrid.Resources>
    <DataGrid.Columns>
        <DataGridComboBoxColumn Header="Options" Width="100"
                                ItemsSource="{Binding Source="{StaticResource proxy}", Path=Data}"/>
    </DataGrid.Columns>
</DataGrid>

BindingProxy is a simple class that derives from Freezable and exposes a Data dependency property.