fix: Make NotifyIcon contextmenu display properly

[IOL0ol1]

Pull request type

Please check the type of change your PR introduces:

• Update
• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes

What is the current behavior?

Issue Number: N/A

NotifyIcon's ContextMenu not display

What is the new behavior?

• now we can see the NotifyIcon's ContextMenu

Other information

The context menu isn't part of the same visual tree and therefore doesn't have the same DataContext.
I have provided a tip here to solve this problem.

[IOL0ol1]

use x:Name=MainWindow is better, but i want less code.

[chucker]

I think x:Reference is discouraged, but I'm only not sure after reading https://learn.microsoft.com/en-us/dotnet/desktop/xaml-services/xreference-markup-extension#xreference-and-wpf.

[IOL0ol1]

   <tray:NotifyIcon
       FocusOnLeftClick="True"
       MenuOnRightClick="True">
       <tray:NotifyIcon.Resources>
           <DiscreteObjectKeyFrame x:Key="proxy" Value="{Binding}"/>
       </tray:NotifyIcon.Resources>
       <tray:NotifyIcon.Menu>
           <ContextMenu  DataContext="{Binding Source={StaticResource proxy},Path=Value}">
               <ui:MenuItem
                   Name="OpenSettings"
                   Command="{Binding OpenSettingsCommand}"
                   CommandParameter="123"
                   Header="{x:Static str:Resources.AppSetting}" />
               <ui:MenuItem
                   Name="Exit"
                   Command="{Binding ExitAppCommand}"
                   Header="{x:Static str:Resources.AppExit}" />
           </ContextMenu>
       </tray:NotifyIcon.Menu>
   </tray:NotifyIcon>

ok,i have plan b

[IOL0ol1]

@chucker
I have provided two of my common practices. My approach is to solve it through XAML:

• Using x:Referenceto traverse the visual tree.
• Using a lazy-loading object (I directly borrowed the DiscreteObjectKeyFramefrom the WPF animation system).

Can we discuss your thoughts? What fixes are planned?

Maybe we could start by getting something done, even if it's not the final solution? The Wpf.Ui.Gallery is a sample project, so we can always change it later if we think of a better way.