Question

I’m creating an app in WPF.

I included a Systray icon using “System.Windows.Forms.NotifyIcon”

the code looks like:

// Create WinForm notify icon
m_NotifyIcon = new System.Windows.Forms.NotifyIcon();
m_NotifyIcon.Icon = Properties.Resources.rocket;
m_NotifyIcon.Visible = true;
// Default Balloon title
m_NotifyIcon.BalloonTipTitle = "Greatest App ever";
m_NotifyIcon.ContextMenu = new System.Windows.Forms.ContextMenu();

// Append default menu items
List<MenuItem> itemList = new List<MenuItem>();
itemList.Insert(0, new MenuItem("Exit", OnExit_Click));
itemList.Insert(0, new MenuItem("-"));
itemList.Insert(0, new MenuItem("Refresh", RefreshConsoleList));
itemList.Insert(0, new MenuItem("Filter: \"" + (String.IsNullOrEmpty(m_Filter) ? "NONE" : m_Filter) + "\"", ChangeFilter_Click));
itemList.Insert(0, new MenuItem("-"));
m_NotifyIcon.ContextMenu.MenuItems.AddRange(itemList.ToArray());

the result looks like this:

Before Refreshing

In the case of the refresh, my application will get a lot of entries, then append these entries in the ContextMenu, the menu will looks like this:

Overflow of MenuItem

As you can see, there is too many MenuItem and because of the overflow, 2 arrows will be displayed (Top and Bottom of the ContextMenu)

Now if the user wants to Exit the application, he have to scroll down, then click on Exit.
If the list is really big, it can annoy the user.

To avoid this, I want to display the ContextMenu already scrolled to the bottom when it pop up (the first MenuItem is visible)

But I didn’t find any event or control to use to Scroll Down programmatically the ContextMenu.

Is it possible to do?

Regards

Yves Desgraupes

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PS: I was unable to directly post the Images because of my reputation (it’s my first post), and post more than 2 links.

the third exemple is here:

yves.desgraupes.free.fr/shared/ContextMenu_OverflowScroll.png

Answer 1

What you could do is use a WPF implementation of the NotifyIcon.

• http://wpfcontrib.codeplex.com/wikipage?title=NotifyIcon&referringTitle=Home

Then you could have a WPF menu, and have more control over how you implement the behaviour you want in the menu.

So you could define a Template for the ContextMenu and get access to the ScrollViewer within the ContextMenu template and then call ScrollToEnd() on it.

Here’s an example that shows how to create a WPF context menu that when it starts up is scrolled to the end. You can use this in your WPF NotifyIcon. Right click on the Button to see the contextmenu.

Note I’ve provided it as a starting point….you may be able to improve the code..reduce some repetitions…but it works….e.g…to get around a glitch when the menu is first displayed it doesn’t scroll to the end I had to trap the SizeChanged event.

<Window x:Class="WpfApplication15.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <Style TargetType="{x:Type ContextMenu}">
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type ContextMenu}">
                        <Border x:Name="border" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
                            <ScrollViewer x:Name="scrollviewer"
Style="{DynamicResource {ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}}"
CanContentScroll="True" >
                                <ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" Margin="{TemplateBinding Padding}"
KeyboardNavigation.DirectionalNavigation="Cycle"/>
                            </ScrollViewer>
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </Window.Resources>
    <Grid>
        <Button x:Name="mybutton">
            <Button.ContextMenu>
                <ContextMenu>
                    <MenuItem Header="Test1"/>
                </ContextMenu>
            </Button.ContextMenu>
            Test Button
        </Button>       
    </Grid>
</Window>

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Windows.Controls.Primitives;

namespace WpfApplication15
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public static T FindVisualChild<T>(DependencyObject depObj) where T : DependencyObject
        {
            if (depObj != null)
            {
                for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
                {
                    DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
                    if (child != null && child is T)
                    {
                        return (T)child;
                    }

                    T childItem = FindVisualChild<T>(child);
                    if (childItem != null) return childItem;
                }
            }
            return null;
        }

        public MainWindow()
        {
            InitializeComponent();

            ContextMenu contextmenu = mybutton.ContextMenu;

            // Add 100 more items

            for (int i = 2; i <= 100; i++)
            {
                MenuItem mi = new MenuItem();
                mi.Header = "Item" + i.ToString();

                contextmenu.Items.Add(mi);
            }

            contextmenu.SizeChanged += new SizeChangedEventHandler(contextmenu_SizeChanged);
            contextmenu.Loaded += new RoutedEventHandler(contextmenu_Loaded);

            mybutton.ContextMenuOpening += new ContextMenuEventHandler(mybutton_ContextMenuOpening);
        }

        void contextmenu_SizeChanged(object sender, SizeChangedEventArgs e)
        {
            ContextMenu contextmenu = mybutton.ContextMenu;

            ScrollViewer sv = FindVisualChild<ScrollViewer>(contextmenu);
            if (sv != null)
            {
                sv.ScrollToEnd();
            }
        }

        void contextmenu_Loaded(object sender, RoutedEventArgs e)
        {
            ContextMenu contextmenu = mybutton.ContextMenu;

            ScrollViewer sv = FindVisualChild<ScrollViewer>(contextmenu);
            if (sv != null)
            {
                sv.ScrollToEnd();
            }
        }

        void mybutton_ContextMenuOpening(object sender, ContextMenuEventArgs e)
        {
            ContextMenu contextmenu = mybutton.ContextMenu;
            ScrollViewer sv = FindVisualChild<ScrollViewer>(contextmenu);
            if (sv != null)
            {
                sv.ScrollToEnd();
            }
        }
    }
}

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On a side note….you might want to limit the height of the ContextMenu…by setting MaxHeight…demo here.

<Page
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
  <Grid>  
  <Button>
  <Button.ContextMenu>
  <ContextMenu MaxHeight="100">
  <MenuItem Header="Test1"/>
  <MenuItem Header="Test2"/>
  <MenuItem Header="Test3"/>
  <MenuItem Header="Test4"/>
  <MenuItem Header="Test5"/>
  <MenuItem Header="Test6"/>
  <MenuItem Header="Test7"/>
  <MenuItem Header="Test8"/>
  <MenuItem Header="Test9"/>
  </ContextMenu>
  </Button.ContextMenu>
  Test Button</Button>
  </Grid>
</Page>