I have a simple object like:
class Item
{
....
public String Measure { get; set; }
public String[] Measures {get; }
}
Which I am trying to bind to a DataGrid with two text columns and a combo box column. For the combo box column, property Measure is the current selection and Measures the possible values.
My XAML is:
<DataGrid Name="recipeGrid" AutoGenerateColumns="False"
CellEditEnding="recipeGrid_CellEditEnding" CanUserAddRows="False"
CanUserDeleteRows="False">
<DataGrid.Columns>
<DataGridTextColumn Header="Food" Width="Auto"
Binding="{Binding Food.Name}" />
<DataGridTextColumn Header="Quantity" IsReadOnly="False"
Binding="{Binding 开发者_C百科Quantity}" />
<DataGridComboBoxColumn Header="Measure" Width="Auto"
SelectedItemBinding="{Binding Path=Measure}"
ItemsSource="{Binding Path=Measures}" />
</DataGrid.Columns>
</DataGrid>
The text column are displayed just fine but the combobox is not - the values are not displayed at all. The binding error is:
System.Windows.Data Error: 2 : Cannot find governing FrameworkElement or FrameworkContentElement for target element. BindingExpression:Path=Measures; DataItem=null; target element is 'DataGridComboBoxColumn' (HashCode=11497055); target property is 'ItemsSource' (type 'IEnumerable')
How do I fix this?
This is hands down the best solution:
http://wpfthoughts.blogspot.com/2015/04/cannot-find-governing-frameworkelement.html
The idea here is that you declare a CollectionViewSource as a static resource and then declaratively bind it to ItemsSource of the DataGridComboBoxColumn.
Create and bind a static CollectionViewSource:
<Page.Resources>
<CollectionViewSource x:Key="Owners" Source="{Binding Owners}"/>
</Page.Resources>
And then bind your target ItemsSource:
ItemsSource="{Binding Source={StaticResource Owners}}"
The problem lies in that Columns does no inherit DataContext.
See more here Binding in a WPF data grid text column
here blogs.msdn.com/vinsibal/archive/2008/12/17/wpf-datagrid-dynamically-updating-datagridcomboboxcolumn.aspx
and here http://blogs.msdn.com/jaimer/archive/2008/11/22/forwarding-the-datagrid-s-datacontext-to-its-columns.aspx
If your measures are common for all objects, then you can make measures static
public String[] Measures { get; }
And your xaml will use it as it's shown below:
<DataGridComboBoxColumn
Header="Role"
SelectedValueBinding="{Binding Role}"
ItemsSource="{Binding Source={x:Static local:ProjectsDataContext.Roles}}"
DisplayMemberPath="Name"/>
Hopefully, it will help.
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