WPF - how to hide menu item if command's CanExecute is false?

wpf command contextmenu menuitem
Gus Cavalcanti picture Gus Cavalcanti · Sep 21, 2010 · Viewed 32.3k times · Source

By default menu items become disabled when its command cannot be executed (CanExecute = false). What is the easiest way to make the menu item visible/collapsed based on the CanExecute method?

Answer

Reddog picture Reddog · Dec 8, 2010

Thanks for the solution. For those wanting explicit XAML this might help:

<Window.Resources>
        <BooleanToVisibilityConverter x:Key="booleanToVisibilityConverter" />
</Window.Resources>

<ContextMenu x:Key="innerResultsContextMenu">
    <MenuItem Header="Open"
              Command="{x:Static local:Commands.AccountOpened}"
              CommandParameter="{Binding Path=PlacementTarget.DataContext, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContextMenu}}}" 
              CommandTarget="{Binding Path=PlacementTarget, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContextMenu}}}"
              Visibility="{Binding Path=IsEnabled, RelativeSource={RelativeSource Self}, Mode=OneWay, Converter={StaticResource booleanToVisibilityConverter}}" 
              />
</ContextMenu>

In my case, the context menu is a resource, so the binding for the visibility must use the RelativeSource Self binding setup.

As a side, for the CommandParameter, you might also pass the DataContext of the item whom was clicked to open the context menu. And in order to route the command bindings to the parent window, you will need to set the CommandTarget accordingly also.

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