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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.

WPF Databinding ContextMenu of Button inside a DataTemplate inside an ItemsControl

I am trying to figure out how I can bind the ContextMenu of the Button that is being added in the ItemsControl I have. Basically, I'm wanting to be able to right click on a button and remove it from the observable collection that sits on my viewmodel. I understand that ContextMenu's are not part of the VisualTree, so using RelativeSource to walk up the tree to find my DataContext hasn't been useful to me.
The end goal of what I want to do is Bind the Command on the MenuItem to the RemoveCommand on my ViewModel and then pass in the Content property of the Button that you right click on so that I can remove it from the observable collection.
Any help on this would be greatly appreciated.
Model:
public class Preset
{
public string Name { get; set; }
}
ViewModel:
public class SettingsWindowViewModel
{
public ObservableCollection<Preset> MyPresets { get; } = new ObservableCollection<Preset>();
private ICommand _plusCommand;
public ICommand PlusCommand => _plusCommand ?? (_plusCommand = new DelegateCommand(AddPreset));
private ICommand _removeCommand;
public ICommand RemoveCommand => _removeCommand ?? (_removeCommand = new DelegateCommand<string>(RemovePreset));
private void AddPreset()
{
var count = MyPresets.Count;
MyPresets.Add(new Preset {Name = $"Preset{count+1}"});
}
private void RemovePreset(string name)
{
var preset = MyPresets.FirstOrDefault(x => string.Equals(x.Name, name, StringComparison.CurrentCultureIgnoreCase));
if (preset!= null)
{
MyPresets.Remove(preset);
}
}
}
XAML:
<Window x:Class="WpfTesting.Esper.Views.SettingsWindow"
x:Name="MainSettingsWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:viewModels="clr-namespace:WpfTesting.Esper.ViewModels"
mc:Ignorable="d"
Title="SettingsWindow" Height="470" Width="612">
<Window.DataContext>
<viewModels:SettingsWindowViewModel/>
</Window.DataContext>
<Window.Resources>
<Style BasedOn="{StaticResource {x:Type MenuItem}}" TargetType="{x:Type MenuItem}" x:Key="PopupMenuItem">
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type MenuItem}">
<Border>
<ContentPresenter ContentSource="Header"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="1*"/>
<RowDefinition Height="35"/>
</Grid.RowDefinitions>
<StackPanel Grid.Row="2" Orientation="Horizontal">
<Button Width="70" Content="Load"/>
<Button Width="70" Content="Save As"/>
<ItemsControl ItemsSource="{Binding MyPresets}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Width="70" Content="{Binding Name}">
<Button.ContextMenu>
<ContextMenu>
<MenuItem Style="{StaticResource PopupMenuItem}" Header="Remove">
<!--
I need to set up binding a Command to a method on the DataContext of the Window, and I need to pass in the Content of the Button that is the parent of the ContextMenu
-->
</MenuItem>
</ContextMenu>
</Button.ContextMenu>
</Button>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<Button Width="20" Background="Transparent" BorderBrush="Transparent" Content="+" FontSize="21.333" HorizontalAlignment="Center" VerticalAlignment="Center" Command="{Binding PlusCommand}"/>
</StackPanel>
</Grid>
</Window>

Using WPF: Binding a ContextMenu to an MVVM Command as an introduction to what Tags can do, I figured out how to do what I was looking for by using multiple Tags to save the Context of what I was looking for.
I first made sure to give my window a x:Name
<Window x:Name="MainSettingsWindow"
Next, on the Button inside my DataTemplate of my ItemsControl, I set a Tag and set it to my Window
<ItemsControl ItemsSource="{Binding MyPresets}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Width="70" Content="{Binding Name}" Tag="{Binding ElementName=MainSettingsWindow}">
Next, in the ContextMenu, I seth the DataContext of the ContextMenu to the Tag I set on the Button, I also needed to create a Tag on the ContextMenu and point it back to the Content Property of the Button so that I can pass that into the CommandParameter
<ContextMenu DataContext="{Binding Path=PlacementTarget.Tag, RelativeSource={RelativeSource Mode=Self}}" Tag="{Binding PlacementTarget.Content, RelativeSource={RelativeSource Mode=Self}}">
At this point, I can now bind my MenuItem correctly using the Command from my ViewModel and the Content Property from the Button
This is the final XAML for my ItemsControl:
<ItemsControl ItemsSource="{Binding MyPresets}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Width="70" Content="{Binding Name}" Tag="{Binding ElementName=MainSettingsWindow}">
<Button.ContextMenu>
<ContextMenu DataContext="{Binding Path=PlacementTarget.Tag, RelativeSource={RelativeSource Mode=Self}}" Tag="{Binding PlacementTarget.Content, RelativeSource={RelativeSource Mode=Self}}">
<MenuItem Header="Remove"
Style="{StaticResource PopupMenuItem}"
Command="{Binding Path=DataContext.RemoveCommand}"
CommandParameter="{Binding Path=Tag, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ContextMenu}}"/>
</ContextMenu>
</Button.ContextMenu>
</Button>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
One thing to note is that I had to change the CommandParameter on my ViewModel to take an Object instead of a String. The reason I did this was because I was getting an exception on the CanExecute method in my DelegateCommand
This is the exception I was getting:
Unable to cast object of type 'MS.Internal.NamedObject' to type 'System.String'.
I'm not sure exactly what's causing that exception to throw, but changing it to Object works ok for me.

I had basically a similar problem, and the solution I found was to use the Messenger class some MVVM frameworks like Devexpress or Mvvm Light have.
Basically you can register in a viewModel to listen for incoming messages. The class itself, at least in the Devexpress implementation works with weak references, so you may not even unregister message handlers and it will not cause memory leaks.
I had used this method for removing on right click tabs from a ObservableCollection, so it was similar to your scenario.
You can have a look here :
https://community.devexpress.com/blogs/wpf/archive/2013/12/13/devexpress-mvvm-framework-interaction-of-viewmodels-messenger.aspx
and here :
https://msdn.microsoft.com/en-us/magazine/jj694937.aspx

Dynamically create ContextMenu

In my application I want to dynamically build up a context-menu. The first MenuItem is static and the second one should be a Separator. All items after the Separator are dynamically created at runtime.
I don't want to use code-behind becaus I'm working with the MVVM-Pattern.
My idea now was to create an interface called IAppMenuItem with the following three implementations
ModifyMenuItem (Static MenuItem)
SeparatorMenuItem
ExecuteMenuItem (Dynamic MenuItem
In the viewmodel of my application I've created an ObservableCollection<IAppMenuItem> which contains the ContextMenu-Items.
Until here everything works fine. My problem is the presentation of the ContextMenu-Items in the UI.
I tried to set the correct controls with the following DataTemplates in the Resources of the view.
<DataTemplate DataType="{x:Type model:SeparatorMenuItem}">
<Separator/>
</DataTemplate>
<DataTemplate DataType="{x:Type model:ModifyMenuItem}">
<MenuItem Header="Edit items"/>
</DataTemplate>
<DataTemplate DataType="{x:Type model:ExecuteMenuItem}">
<MenuItem Header="{Binding DisplayText}"/>
</DataTemplate>
The definition of my ContextMenu is just:
<ContextMenu ItemsSource="{Binding MenuItemsCollection}"/>
The DataTemplates are working fine, but the controls are drawn inside a MenuItem. So for example for the Separator I see in the UI a Separator-Control inside a MenuItem-Control. But I need the Separator to be the Control.
Anyone have an idea how to set the Controls inside the DataTemplates directly to the contextmenu?
Update:
The complete ContextMenu looks like:
<ToggleButton Margin="0,0,10,0"
AutomationProperties.Name="Update"
AutomationProperties.AutomationId="Update_List"
Content="Update"
AttachedProperties:ButtonExtensions.IsDropDownButton="True"
Style="{StaticResource GenericToggleButtonStyle}">
<ToggleButton.ContextMenu>
<controls:CustomContextMenu ItemsSource="{Binding MenuItemsCollection}">
<ContextMenu.Resources>
<ResourceDictionary>
<DataTemplate DataType="{x:Type model:ExecuteMenuItem}">
<MenuItem Header="{Binding DisplayText}"/>
</DataTemplate>
<DataTemplate DataType="{x:Type model:ModifyMenuItem}">
<MenuItem Header="Edit items"/>
</DataTemplate>
</ResourceDictionary>
</ContextMenu.Resources>
</controls:CustomContextMenu>
</ToggleButton.ContextMenu>
</ToggleButton>
The GenericToggleButtonStyle is just:
<Style x:Key="GenericToggleButtonStyle" TargetType="ToggleButton"
BasedOn="{StaticResource {x:Type ToggleButton}}">
<Setter Property="MinWidth" Value="80" />
<Setter Property="Height" Value="22" />
<Setter Property="Padding" Value="3,1" />
</Style>
Here is a screenshot of the MenuItems

It seems when you set the ItemSource property on a ContextMenu the default ItemContainer used is MenuItem. This is why the Separator is rendered as a MenuItem.
You can fix this by implementing your own ContextMenu control that inherits from ContextMenu.
You need to override the IsItemItsOwnContainerOverride and GetContainerForItemOverride methods.
Please see my example below:
public class CustomContextMenu
: ContextMenu
{
private bool _mustGenerateAsSeparator = false;
protected override bool IsItemItsOwnContainerOverride(object item)
{
_mustGenerateAsSeparator = (item is SeparatorMenuItem);
return base.IsItemItsOwnContainerOverride(item);
}
protected override System.Windows.DependencyObject GetContainerForItemOverride()
{
if (_mustGenerateAsSeparator)
{
return new Separator { Style = this.FindResource(MenuItem.SeparatorStyleKey) as System.Windows.Style };
}
else
{
return base.GetContainerForItemOverride();
}
}
}
Style = this.FindResource(MenuItem.SeparatorStyleKey) as System.Windows.Style is needed as you have to apply the default MenuItem.SeparatorStyleKey style to get the default separator style.
This link pointed me into the right direction http://drwpf.com/blog/category/item-containers/
How to use the custom control in XAML:
window declaration :xmlns:cnt="your namespace"
<Label Content="Dynamic Menu">
<Label.ContextMenu>
<cnt:CustomContextMenu x:Name="contextMenu" ItemsSource="{Binding MenuItemsCollection}">
<ContextMenu.Resources>
<ResourceDictionary>
<DataTemplate DataType="{x:Type model:ExecuteMenuItem}">
<MenuItem Header="{Binding DisplayText}"></MenuItem>
</DataTemplate>
<DataTemplate DataType="{x:Type model:ModifyMenuItem}">
<MenuItem Header="{Binding DisplayText}"></MenuItem>
</DataTemplate>
</ResourceDictionary>
</ContextMenu.Resources>
</model:CustomContextMenu>
</Label.ContextMenu>
</Label>
Second Part of the question:
Update your data templates to use TextBlock as they will be rendered inside a MenuItem, please see below:
<DataTemplate DataType="{x:Type model:ModifyMenuItem}">
<TextBlock Header="Edit items"/>
</DataTemplate>
<DataTemplate DataType="{x:Type model:ExecuteMenuItem}">
<TextBlock Header="{Binding DisplayText}"/>
</DataTemplate>

Method in ContextMenu for (Hierarchical)DataTemplate calls TreeViewItem's method instead of the one in ViewModel

I have a TreeView with multiple HierarchicalDataTemplate & DataTemplate items and I'm using Caliburn Micro for mvvm. The ItemsSource for the treeview is pointing to a collection in the viewmodel called 'TreeData' and I tried adding a specific ContextMenu for each HierarchicalDataTemplate & DataTemplate.
In the ContextMenu I use the caliburn functionality "cal:Message.Attach" to call a function in the
I made a smaller example of the treeview to illustrate the problem.
In the ViewModel (the collection object):
public class MyViewModel
{
// TreeData object
public ObservableCollection<TestRoot> TreeData = new ObservableCollection<TestRoot>()
{
new TestRoot()
{
Name = "Root item"
}
};
// the function on the viewmodel that should be called
public void DoSomething(object item)
{
MessageBox.Show("MyViewModel - DoSomething called");
}
}
The collection object:
public class TestRoot
{
public string Name { get; set; }
// caliburn calls this instead of the one on the viewmodel
public void DoSomething(object item)
{
MessageBox.Show("TestRoot - DoSomething called");
}
}
MyView.xaml treeview with only one (Hierarchical)DataTemplate:
<TreeView Margin="5" ItemsSource="{Binding TreeData}">
<TreeView.Resources>
<DataTemplate DataType="{x:Type vm:TestRoot}" >
<StackPanel Orientation="Horizontal">
<StackPanel.ContextMenu>
<ContextMenu>
<!-- caliburn (?) chooses the method on the collection object, not the viewmodel -->
<MenuItem Header="test dosomething" cal:Message.Attach="DoSomething($dataContext)"></MenuItem>
</ContextMenu>
</StackPanel.ContextMenu>
<TextBlock Text="{Binding Name}"/>
</StackPanel>
</DataTemplate>
</TreeView.Resources>
</TreeView>
In another piece of code, I placed the ContextMenu in the TreeView.ContextMenu. There it worked as it 'should', pointing to the method on the viewmodel.
Looking around for a solution, I see things like "inheritance context". I think it might have something to do with it, but I'm not sure. How can I tell caliburn it must look in the viewmodel for my method, instead of the item in the TreeView I clicked on?
Or is there another possibility? For example: defining the different ContextMenus in the Resources and pointing them to the DataTemplates? But, wont that cause the exact same problem?
Please note that I'd like to keep the code-behind as minimal as possible. Thanks
update
For the completeness, here's the real development code. This should be right, no?
<TreeView ItemsSource="{Binding OrderTreeViewData.OrderTreeViewCategories}"
cal:Message.Attach="[Event SelectedItemChanged] = [Action OnSelectedItemChanged($this)]">
<TreeView.ItemContainerStyle>
<Style TargetType="{x:Type TreeViewItem}">
<!-- We have to select the item which is right-clicked on -->
<EventSetter Event="TreeViewItem.PreviewMouseRightButtonDown"
Handler="TreeViewItem_PreviewMouseRightButtonDown"/>
<!-- set expanded -->
<Setter Property="TreeViewItem.IsExpanded" Value="True"/>
</Style>
</TreeView.ItemContainerStyle>
<TreeView.Resources>
<!-- dredge nodes -->
<HierarchicalDataTemplate DataType="{x:Type programs:DredgeRoot}"
ItemsSource="{Binding Dredgezones}">
<StackPanel>
<StackPanel.ContextMenu>
<ContextMenu DataContext="{Binding Path=PlacementTarget, RelativeSource={RelativeSource Self}}">
<MenuItem Header="Add dredge zone" cal:Message.Attach="TreeViewAddDredgeZone($datacontext)"></MenuItem>
</ContextMenu>
</StackPanel.ContextMenu>
<TextBlock Text="{Binding Name}"/>
</StackPanel>
</HierarchicalDataTemplate>
<!-- omitted other templates -->
</TreeView.Resources>
</TreeView>

Unfortunately there is still one tricky part to deal with. Due to the specific Popup behavior it doesn't inherit DataContext. To access proper context you have to get the PlacementTarget:
<StackPanel Tag="{Binding DataContext, RelativeSource={RelativeSource Self}}">
<StackPanel.ContextMenu>
<ContextMenu DataContext="{Binding Path=PlacementTarget.Tag, RelativeSource={RelativeSource Self}}">
<MenuItem Header="test dosomething" cal:Message.Attach="DoSomething"/>
</ContextMenu>
</StackPanel.ContextMenu>
</StackPanel>

I think you have the nearly same problem as me, maybe see this topic : Bind contextMenu to a different viewmodel from treeview
You can try to use a command :
Try to change you code to :
<ContextMenu x:Key="MyContextMenu">
<MenuItem Header="Add dredge zone" Command="{Binding PlacementTarget.Tag.DataContext.TreeViewAddDredgeZoneCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ContextMenu}}"
CommandParameter="{Binding}"></MenuItem>
</ContextMenu>
Then add to your hierarchicalDataTemplate a Tag and ContextMenu
<HierarchicalDataTemplate DataType="{x:Type programs:DredgeRoot}"
ItemsSource="{Binding Dredgezones}" Tag="{Binding RelativeSource={RelativeSource AncestorType=UserControl}} ContextMenu="{StaticResource MyContextMenu}">
And in your viewmodel you can add your command with something like this :
public ICommand TreeViewAddDredgeZoneCommand
{
//your code here
}

Binding an item inside DataTemplate

In my xaml file, I have:
<DataTemplate DataType="{x:Type Configuration:Drivers}">
<ItemsControl ItemsSource="{Binding Cars}" FontWeight="Normal" />
<DataTemplate>
<DataTemplate DataType="{x:Type Configuration:Car}">
<UniformGrid HorizontalAlignment="Stretch" Margin="5,1,5,2" Columns="2">
<CheckBox IsChecked="{Binding Enabled, UpdateSourceTrigger=PropertyChanged}"/>
<CheckBox Visibility="{Binding SaveImage, UpdateSourceTrigger=PropertyChanged}"/>
</UniformGrid>
</DataTemplate>
For each car, it has: Enabled property but does not have SaveImage property.
Car
{
public bool Enabled {}
}
The 'SaveImage' is set in globally. I don't know how to bind that: bool SaveImage inside the DataTemplate?

DataTemplates are an encapsulation boundary, so you cannot allways use FindAncestor to get the desired data. A good solution is to put your ViewModel in your XAML as a StaticResource and then set the DataContext of you LayoutRoot grid to this StaticResource, then all other DataTemplates can access the DataContext via the same StaticResource
EXAMPLE
<Window.Resources>
<local:MyViewModel x:Key="viewmodel" />
<DataTemplate DataType="{x:Type Configuration:Car}">
<UniformGrid HorizontalAlignment="Stretch" Margin="5,1,5,2" Columns="2">
<CheckBox IsChecked="{Binding Enabled, UpdateSourceTrigger=PropertyChanged}"/>
<CheckBox Visibility="{Binding Source={StaticResource viewmodel},
Path=SaveImage, UpdateSourceTrigger=PropertyChanged}"/>
</UniformGrid>
</DataTemplate>
</Window.Resources>
<Grid DataContext="{Binding Source={StaticResource viewmodel}}">
</Grid>

If SaveImage is available in the DataContext of the ItemsControl you can bind to it this way:
<CheckBox IsChecked="{Binding DataContext.SaveImage, UpdateSourceTrigger=PropertyChanged,
RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}}"/>

Solution 1:
You can try RelativeSource to Bind IsCheck to the abcestor object.
{Binding Path=SaveImage, RelativeSource={RelativeSource AncestorType={x:Type typeOfAncestor}}}
Solution 2:
Add a property SaveImage to view-model class Car and ref to model SaveImage.It's not a good solution.