How do you add access keys (shortcuts) to a WPF ContextMenu, programmatically?

Question

I already have the following:

var myContextMenu = new System.Windows.Controls.ContextMenu();

var exitItem = new MenuItem();
exitItem.Header = "E_xit";
exitItem.Item.Click += new RoutedEventHandler(new System.EventHandler(ExitProgram));
myContextMenu.Items.Add(exitItem);

This causes my context menu to display the Exit menu item, with an underlined "x". However, pressing x does nothing. Clicking the menu item works fine.

How can I associate an event with the x key? Please note that this has to be done programmatically in my context. I cannot compose this solution in the XAML in front.

See if you can make use of the already build-in WPF commands via ApplicationCommands class: http://msdn.microsoft.com/en-us/library/system.windows.input.applicationcommands.aspx — S2S2, Jun 11 '12 at 15:44

score 3 · Answer 1 · answered Jun 11 '12 at 15:11

The usual way to add shortcuts is as follows:

var exitCommand = new RelayCommand(_ => ExitProgram());
        var exitItem = new MenuItem(); 
        exitItem.Header = "E_xit";
        exitItem.Command = exitCommand;
        myContextMenu.Items.Add(exitItem);

        InputBindings.Add(new KeyBinding(exitCommand, new KeyGesture(Key.X, ModifierKeys.Alt));

The RelayCommand class used here is not the part of WPF but it's widely used in MVVM-based apps.

Please note though, that you cannot set your shortcut to X without modifiers. Quote from MSDN

In most cases, a KeyGesture must be associated with one or more ModifierKeys. The exceptions to this rule are the function keys and the numeric keypad keys, which can be a valid KeyGesture by themselves. For example, you can create a KeyGesture by using only the F12 key, but to use the X key in a KeyGesture it must be paired with a modifier key.

If for some reason you need to use X w/o modifiers - you will have to handle keyboard events (eg KeyDown) and react accordingly

It is extremely common to see menus in windows (context menus or File menu, etc.), which have hotkeys without modifiers. Are these seriously all using keyboard events? — Jordan Morris, Jun 13 '12 at 09:47
Can't say for sure, at least it is not possible using InpupBindings in WPF. Anyway, it's very easy to implement using keyboard events: private void mainWindow_PreviewKeyDown(object sender, System.Windows.Input.KeyEventArgs e) { if (e.Key == System.Windows.Input.Key.X) App.Current.Shutdown(); } — olldman, Jun 14 '12 at 11:20

score 0 · Answer 2 · answered Jul 30 '12 at 19:23

This works fine for me:

using System.Windows;
using System.Windows.Controls;

namespace WpfApplication5
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            Loaded += new RoutedEventHandler(MainWindow_Loaded);
        }

        private void MainWindow_Loaded(object sender, RoutedEventArgs e)
        {
            // Create menu item.
            MenuItem exitMenuItem = new MenuItem();
            exitMenuItem.Header = "E_xit";
            exitMenuItem.Click +=new RoutedEventHandler(exitMenuItem_Click);

            // Create contextual menu.
            ContextMenu contextMenu = new ContextMenu();
            contextMenu.Items.Add(exitMenuItem);

            // Attach context-menu to something.
            myButton.ContextMenu = contextMenu; // Assuming there's a button on window named "myButton".
        }

        public void exitMenuItem_Click(object sender, RoutedEventArgs e)
        {
            // This gets executed when user right-clicks button, and presses x down on their keyboard.
            // TODO: Exit logic.
        }
    }
}


<Window x:Class="WpfApplication5.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow">
    <Grid>
        <Button x:Name="myButton" />
    </Grid>
</Window>

The exitMenuItem_Click handler gets executed when the user right-clicks the button and presses 'x' on their keyboard. Are you not seeing this happen?

Correct, I am not seeing this. It may be worth noting that in my context there is no Window. I am creating a context menu for a system tray icon. — Jordan Morris, Jan 14 '13 at 10:57

How do you add access keys (shortcuts) to a WPF ContextMenu, programmatically?

2 Answers2

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