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How to bind to another function, inside a container with ItemsSource [duplicate]

I have an ItemsControl whose for the ItemTemplate DataTemplate contains a Button. I want the Command on the button to bind to a Command on the DataContext of the ItemsControl, not the ItemTemplate. I think the solution has to do with using RelativeSource, but my attempts so far have failed:
<ItemsControl ItemsSource="{Binding Games}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Command="{Binding Path=GameSelectedCommand, Source={RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}}"
CommandParameter="{Binding}"
Style="{StaticResource MenuButtonStyle}"
Content="{Binding Name}"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
How can I get the Button to bind to the GameSelectedCommand of the ItemsControl's DataContext object?

You're setting the source of the binding to the ItemsControl itself. Therefore, you'll need to dereference the DataContext of the ItemsControl:
Command="{Binding DataContext.GameSelectedCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}}"
How would you have known this? Take a look at your debug output window when running the app. You'll see a message along the lines of "Cannot resolve property 'GameSelectedCommand' on type 'ItemsControl'".

A command from a context menu that does not work

Well, I have a WPF project and I'm using Visual Studio 2010. I'm using C# and XAML, and I'm using the MVVM pattern.
The problem I have must be simple but I just can't see why it's not working.
Alright, so I have a project with a ListBox. In that ListBox are many ChatNodes; each represented visually. The visual element for a ChatNode is here:
<ControlTemplate x:Key="NodeVisualTemplate">
<Grid>
<Border BorderThickness="2" Margin="2" CornerRadius="5,5,5,5" BorderBrush="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBox}}, Path=DataContext.SelectionMode, Converter={StaticResource SelectionModeToColourConverter}}" ContextMenu="{StaticResource ChatNodeMenu}">
<StackPanel Opacity="{Binding IsInvisibleNode, Converter={StaticResource ResourceKey=VisibleToOpacityConverter}}">
<TextBlock Text="Test" Background="AntiqueWhite"/>
<TextBlock Text="{Binding Path=NodeText}" Background="Aqua"/>
<StackPanel Orientation="Horizontal">
<TextBox Text="Type here" MinWidth="50"/>
<Image Source="{StaticResource ImgFolder}" Margin="0,0,5,0" Width="32" Height="32"/>
</StackPanel>
</StackPanel>
</Border>
</Grid>
</ControlTemplate>
I draw your attention to the BorderBrush for the Border. I will show that again here:
BorderBrush="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBox}}, Path=DataContext.SelectionMode, Converter={StaticResource SelectionModeToColourConverter}}"
This code sits inside a ListBoxItem and is able to find the parent ListBox and then access a property of it. This works fine. The property is in a view model called ChatNodeListViewModel and looks like this:
private int _selectionMode = 0;
public int SelectionMode
{
get { return _selectionMode; }
set
{
if (_selectionMode != value)
{
_selectionMode = value;
RaisePropertyChanged("SelectionMode");
}
}
}
I mention it specifically because another thing which is almost identical is not working, even though this BorderBrush code is working.
So, on to the not working part.
In that same ControlTemplate above, we see a ContextMenu, called 'ChatNodeMenu'. This is as follows:
<ContextMenu x:Key="ChatNodeMenu" >
<MenuItem Header="Remove" Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBox}}, Path=DataContext.RemoveChatNodeCommand}" />
</ContextMenu>
It has the same binding, only this time it is for a Command called 'RemoveChatNodeCommand'. The menu does appear on a right click on a ChatNode, but the command does not run. I have actually used almost identical code in other parts of my project so I assume it's correct... but clearly there is an error somewhere.
So where is this command? It is in the view model called 'ChatNodeListViewModel' and I will present it here:
void RemoveChatNodeExecute()
{
MessageBox.Show("Remove chat node");
return;
}
bool CanRemoveChatNode()
{
return true;
}
public ICommand RemoveChatNodeCommand { get { return new RelayCommand(RemoveChatNodeExecute, CanRemoveChatNode); } }
I have also used this in many places throughout my code and it's worked every time but this one.
So, either there's a fault in the code or perhaps a simple mistake. I've checked the name of the command and re-copied it several times. I've checked the other parts of my code where I've used the same code, but I can't see anything wrong. I've cleaned and rebuilt my project just in case.
If anyone can venture a guess, I would be very happy with that.

The ListBox is not a visual ancestor of a ContextMenu but you could set the Tag property of the Border to the ListBox and then bind to the PlacementTarget of the ContextMenu:
<Border ... Tag="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBox}}" ContextMenu="{StaticResource ChatNodeMenu}">
<MenuItem Header="Remove" Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContextMenu}}, Path=PlacementTarget.Tag.DataContext.RemoveChatNodeCommand}" />

I have same issue related to conextmenu not able to work on command. could you help me to find solution.
<GridViewColumn>
<GridViewColumn.CellTemplate>
<DataTemplate>
<Button Content="test2">
<Button.ContextMenu>
<ContextMenu>
<MenuItem Header="rr2" Command="{Binding DataContext.NextCommand, RelativeSource={RelativeSource AncestorType={x:Type ListView}}}" CommandParameter="{Binding}" ></MenuItem>
</ContextMenu>
</Button.ContextMenu>
</Button>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>

Binding in ResourceDictionary not working

I have a ContextMenu in a ResourceDictionary. The ContextMenu should hide or show depending on the value of a view-model property, but it does not work.
This is my XAML code (ControlBase derives from UserControl):
<control1:ControlBase>
<UserControl.Resources>
<ResourceDictionary>
<HierarchicalDataTemplate ItemsSource="{Binding InfraNetworkItems}">
<StackPanel>
<StackPanel.ContextMenu>
<ContextMenu DataContext="{Binding PlacementTarget.DataContext,
RelativeSource={RelativeSource Self}}">
<MenuItem Header="Delete"
Visibility="{Binding
DataContext.MyViewModel.DeleteEnabled,
RelativeSource={RelativeSource Mode=FindAncestor,
AncestorType=control1:ControlBase},
Converter={StaticResource
BooleanVisibilityConverter}}" />
</ContextMenu>
</StackPanel.ContextMenu>
</StackPanel>
</HierarchicalDataTemplate>
</ResourceDictionary>
</UserControl.Resources>
</control1:ControlBase>
DeleteEnabled is a bool property on the view-model.
My previous attempts of solving the problem are based on this assumptions:
The ContextMenu is inside a HierarchicalDataTemplate which has the ItemsSource set. My property is not a member of this ItemSource, it belongs to the view-model. Therefore I've tried this line of code, but without any effect:
Visibility="{Binding DataContext.MyViewModel.DeleteEnabled,
RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=control1:ControlBase},
Converter={StaticResource BooleanVisibilityConverter}}"
But if I copy the DeleteEnabled property from the view-model to the ItemSource object, it works:
Visibility="{Binding DeleteEnabled, Converter={StaticResource BooleanVisibilityConverter}}"

what is the DataContext of your view? If it's an instance of MyViewModel you have to change the path of your Binding.
Please try this one:
<Visibility="{Binding DataContext.DeleteEnabled, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=control1:ControlBase}, Converter={StaticResource BooleanVisibilityConverter}}" />
With setting the path to DataContext you already have access to your viewmodel and of course to the DeleteEnabled-Property.
Hope this helps.

Binding to Usercontrol Datacontext instead of SelectedItems datacontext

I have a listbox, where a grid with textboxes shows the listboxs currently selecteditems data. (Code below)
The problem is that i want a delete button inside this grid, however the command it uses lies in the Usercontrols DataContext. How do I make the button recieve the command binding inside the UserControls Datacontext?
Following code lies inside a grid where the visual trees root is a UserControl.
<ListBox Name="list" ItemTemplate="{StaticResource listTemplate}" ItemsSource="{Binding listCollection, UpdateSourceTrigger=PropertyChanged}">
</ListBox>
<Grid DataContext="{Binding ElementName=list, Path=SelectedItem}" Grid.Row="1">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"></RowDefinition>
<RowDefinition Height="Auto"></RowDefinition>
</Grid.RowDefinitions>
<TextBlock Margin="7">Name:</TextBlock>
<TextBox Margin="5" Grid.Column="1" Text="{Binding Path=Name}"></TextBox>
<Button Grid.Row="1" Command="{Binding DeleteSelectedItemCommand}">Delete Selected Item</Button>
</Grid>

You need to change DataContext, provide same Name for UserControl and then
Command="{Binding ElementName=Name, Path=DeleteSelectedItemCommand}"

You mean you want to fire the button's command on your UserControls DataContext IE your vm?
Then you need this binding;
<Button Grid.Row="1" Command="{Binding Path=DeleteSelectedItemCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type YourControl}}}">Delete Selected Item</Button>
Basicly this just traverse up your xaml tree and fetch datacontext from the control called YourControl. You could set UserControl here. The cool thing about this kind of binding is that you may track back the datacontext of any items up the chain :)
This document is still very handy for bindings that are a bit tricky :)
Cheers,
Stian

The trick was to wire up the DataContext using Stians reference.
<Button
DataContext="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType {x:Type UserControl}}, Path=DataContext}"
Command="{Binding Path=DeleteSelectedItemCommand}">
</Button>

Access parents from DataTemplate in external XAML file

I have an ItemsControl that uses a DataTemplate which is located in an external ResourceDictionary.xaml:
<ResourceDictionary ... >
<DataTemplate x:Key="My_UserControl">
<local:MyUserControl/>
</DataTemplate>
MyUserControl.xaml file:
<UserControl ...>
<Button Content="{Binding Path=Test, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}"/>
<UserControl/>`
MainWindow.xaml uses that template in an ItemsControl.
The binding to the Window in UserControl doesn't work.
How do I bind from an external file like this UserControl to any parent, using RelativeSource so it works ?
Thanks

Try
<Button Content="{Binding Path=DataContext.Test, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}"/>