This article shows how you can bind to a property located in the data context of your parent which is not accessible to the data template item in silverlight, also as silverlight does not fully support 'relative source' is cannot be used.
Introduction
Using parent data context property from the data template item in silverlight
Objective
Bind to the property located in the Data Context of parent control from Data template Item
Using the code
In below image you can see the Update and Delete buttons in the data grid which should be bound to the corresponding commands located in the data context of the containing page.
Below is a data template button which is bound with the 'Edit' command located in the view model of the page,
while the button itself is in the Data Grid bound with a collection as a data context, so button cannot access the
parent data context property(Edit command).
<sdk:DataGridTemplateColumn>
<sdk:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<Button Content="Update" Padding="5" Margin="5" Command="{Binding Path=Edit,Source={StaticResource ViewModel}}" FontSize="11" Height="26" Width="70" ></Button>
</DataTemplate>
</sdk:DataGridTemplateColumn.CellEditingTemplate>
</sdk:DataGridTemplateColumn>As you can see in the above code button is bound with the Edit command and the source property is a static view Model, which is the data context of the page.
xmlns:local="clr-namespace:SilverlightApplication1"
mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480"
Title="About"
Style="{StaticResource PageStyle}" x:Name="Page">
<navigation:Page.Resources>
<local:StudentViewModel x:Key="ViewModel"/>
</navigation:Page.Resources>so, we have to declare the namespace of the view model class as above and then declare it as a static resource in the resource tag of the page.
Conclusion
The article shows how you can bind your control with a property that is located in the data context of parent control not to the control in which the item exist.