根据事件更改托盘图标

Question

I have code that will start process in tray (task bar). After right click on tray icon it will show menu. After clicking on first menu item winform window starts. This winform shows status about the notepad process. My goal is to change the tray icon based on the status of notepad (if notepad is running then show online.ico otherwise show offline.ico ). If I understand correct then my code is starting/stopping System.Windows.Forms.Timer every time winform window is opened/closed and I'm not sure if this is the best possible approach. My guess is that I need to somehow start timer "outside" of OnMenuItem1ClickEventFn so it can somehow reload *.ico files. Following script is heavily inspired by this site:

Add-Type -AssemblyName System.Windows.Forms    
Add-Type -AssemblyName System.Drawing

function Test-Notepad {
    [bool](Get-Process -Name 'notepad' -ErrorAction SilentlyContinue)
}


function OnMenuItem1ClickEventFn () {
    # Build Label object
    $Label = New-Object System.Windows.Forms.Label
        $Label.Name = "labelName"
        $Label.AutoSize = $True

    # Set and start timer
    $timer = New-Object System.Windows.Forms.Timer
    $timer.Interval = 1000
    $timer.Add_Tick({
        if ($Label){
            $Label.Text = if (Test-Notepad) { "Notepad is running" } else { "Notepad is NOT running" }
        }
    })
    $timer.Start()


    # Build Form object
    $Form = New-Object System.Windows.Forms.Form
        $Form.Text = "My Form"
        $Form.Size = New-Object System.Drawing.Size(200,200)
        $Form.StartPosition = "CenterScreen"
        $Form.Topmost = $True
        $Form.Add_Closing({ $timer.Dispose() })  # Dispose() also stops the timer.
        $Form.Controls.Add($Label)               # Add label to form
        $form.ShowDialog()| Out-Null             # Show the Form
}


function OnMenuItem4ClickEventFn () {
    $Main_Tool_Icon.Visible = $false
    $window.Close()
    Stop-Process $pid
}


function create_taskbar_menu{
    # Create menu items
    $Main_Tool_Icon = New-Object System.Windows.Forms.NotifyIcon
    $Main_Tool_Icon.Text = "Icon Text"
    $Main_Tool_Icon.Icon = $icon
    $Main_Tool_Icon.Visible = $true

    $MenuItem1 = New-Object System.Windows.Forms.MenuItem
    $MenuItem1.Text = "Menu Item 1"

    $MenuItem2 = New-Object System.Windows.Forms.MenuItem
    $MenuItem2.Text = "Menu Item 2"

    $MenuItem3 = New-Object System.Windows.Forms.MenuItem
    $MenuItem3.Text = "Menu Item 3"

    $MenuItem4 = New-Object System.Windows.Forms.MenuItem
    $MenuItem4.Text = "Exit"


    # Add menu items to context menu
    $contextmenu = New-Object System.Windows.Forms.ContextMenu
    $Main_Tool_Icon.ContextMenu = $contextmenu
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem1)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem2)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem3)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem4)


    $MenuItem4.add_Click({OnMenuItem4ClickEventFn})
    $MenuItem1.add_Click({OnMenuItem1ClickEventFn})
}


$Current_Folder = split-path $MyInvocation.MyCommand.Path

# Add assemblies for WPF and Mahapps
[System.Reflection.Assembly]::LoadWithPartialName('System.Windows.Forms')    | out-null
[System.Reflection.Assembly]::LoadWithPartialName('presentationframework')   | out-null
[System.Reflection.Assembly]::LoadWithPartialName('System.Drawing')          | out-null
[System.Reflection.Assembly]::LoadWithPartialName('WindowsFormsIntegration') | out-null
# [System.Reflection.Assembly]::LoadFrom("Current_Folder\assembly\MahApps.Metro.dll")  | out-null

# Choose an icon to display in the systray
$icon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/online.ico")
# use this icon when notepad is not running
# $icon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/offline.ico")


create_taskbar_menu

# Make PowerShell Disappear - Thanks Chrissy
$windowcode = '[DllImport("user32.dll")] public static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);'
$asyncwindow = Add-Type -MemberDefinition $windowcode -name Win32ShowWindowAsync -namespace Win32Functions -PassThru
$null = $asyncwindow::ShowWindowAsync((Get-Process -PID $pid).MainWindowHandle, 0)




# Use a Garbage colection to reduce Memory RAM
# https://dmitrysotnikov.wordpress.com/2012/02/24/freeing-up-memory-in-powershell-using-garbage-collector/
# https://docs.microsoft.com/fr-fr/dotnet/api/system.gc.collect?view=netframework-4.7.2
[System.GC]::Collect()

# Create an application context for it to all run within - Thanks Chrissy
# This helps with responsiveness, especially when clicking Exit - Thanks Chrissy
$appContext = New-Object System.Windows.Forms.ApplicationContext
[void][System.Windows.Forms.Application]::Run($appContext)

EDITED: working solution based on @BACON answer

# Toggle following two lines
Set-StrictMode -Version Latest
# Set-StrictMode -Off

Add-Type -AssemblyName System.Windows.Forms    
Add-Type -AssemblyName System.Drawing

function Test-Notepad {
    [bool](Get-Process -Name 'notepad' -ErrorAction SilentlyContinue)
}


function OnMenuItem1ClickEventFn () {
    # Build Form object
    $Form = New-Object System.Windows.Forms.Form
        $Form.Text = "My Form"
        $Form.Size = New-Object System.Drawing.Size(200,200)
        $Form.StartPosition = "CenterScreen"
        $Form.Topmost = $True
        $Form.Controls.Add($Label)               # Add label to form
        $form.ShowDialog()| Out-Null             # Show the Form
}


function OnMenuItem4ClickEventFn () {
    $Main_Tool_Icon.Visible = $false

    [System.Windows.Forms.Application]::Exit()
}


function create_taskbar_menu{
    # Create menu items
    $MenuItem1 = New-Object System.Windows.Forms.MenuItem
    $MenuItem1.Text = "Menu Item 1"

    $MenuItem2 = New-Object System.Windows.Forms.MenuItem
    $MenuItem2.Text = "Menu Item 2"

    $MenuItem3 = New-Object System.Windows.Forms.MenuItem
    $MenuItem3.Text = "Menu Item 3"

    $MenuItem4 = New-Object System.Windows.Forms.MenuItem
    $MenuItem4.Text = "Exit"


    # Add menu items to context menu
    $contextmenu = New-Object System.Windows.Forms.ContextMenu
    $Main_Tool_Icon.ContextMenu = $contextmenu
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem1)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem2)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem3)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem4)


    $MenuItem4.add_Click({OnMenuItem4ClickEventFn})
    $MenuItem1.add_Click({OnMenuItem1ClickEventFn})
}


$Current_Folder = split-path $MyInvocation.MyCommand.Path

# Add assemblies for WPF and Mahapps
[System.Reflection.Assembly]::LoadWithPartialName('System.Windows.Forms')    | out-null
[System.Reflection.Assembly]::LoadWithPartialName('presentationframework')   | out-null
[System.Reflection.Assembly]::LoadWithPartialName('System.Drawing')          | out-null
[System.Reflection.Assembly]::LoadWithPartialName('WindowsFormsIntegration') | out-null
# [System.Reflection.Assembly]::LoadFrom("Current_Folder\assembly\MahApps.Metro.dll")  | out-null

# Choose an icon to display in the systray
$onlineIcon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/online.ico")
# use this icon when notepad is not running
$offlineIcon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/offline.ico")

$Main_Tool_Icon = New-Object System.Windows.Forms.NotifyIcon
$Main_Tool_Icon.Text = "Icon Text"
$Main_Tool_Icon.Icon = if (Test-Notepad) { $onlineIcon } else { $offlineIcon }
$Main_Tool_Icon.Visible = $true

# Build Label object
$Label = New-Object System.Windows.Forms.Label
    $Label.Name = "labelName"
    $Label.AutoSize = $True

# Initialize the timer
$timer = New-Object System.Windows.Forms.Timer
$timer.Interval = 1000
$timer.Add_Tick({
    if ($Label){
        $Label.Text, $Main_Tool_Icon.Icon = if (Test-Notepad) {
            "Notepad is running", $onlineIcon
        } else {
            "Notepad is NOT running", $offlineIcon
        }
    }
})
$timer.Start()

create_taskbar_menu

# Make PowerShell Disappear - Thanks Chrissy
$windowcode = '[DllImport("user32.dll")] public static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);'
$asyncwindow = Add-Type -MemberDefinition $windowcode -name Win32ShowWindowAsync -namespace Win32Functions -PassThru
$null = $asyncwindow::ShowWindowAsync((Get-Process -PID $pid).MainWindowHandle, 0)

# Use a Garbage colection to reduce Memory RAM
# https://dmitrysotnikov.wordpress.com/2012/02/24/freeing-up-memory-in-powershell-using-garbage-collector/
# https://docs.microsoft.com/fr-fr/dotnet/api/system.gc.collect?view=netframework-4.7.2
[System.GC]::Collect()

# Create an application context for it to all run within - Thanks Chrissy
# This helps with responsiveness, especially when clicking Exit - Thanks Chrissy
$appContext = New-Object System.Windows.Forms.ApplicationContext
try
{
    [System.Windows.Forms.Application]::Run($appContext)    
}
finally
{
    foreach ($component in $timer, $Main_Tool_Icon, $offlineIcon, $onlineIcon, $appContext)
    {
        # The following test returns $false if $component is
        # $null, which is really what we're concerned about
        if ($component -is [System.IDisposable])
        {
            $component.Dispose()
        }
    }

    Stop-Process -Id $PID
}

Answer 1

You already have code to set the icon used by the NotifyIcon ...

$Main_Tool_Icon.Icon = $icon

...and to define the icons to use...

# Choose an icon to display in the systray
$icon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/online.ico")
# use this icon when notepad is not running
# $icon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/offline.ico")

...and to periodically test if Notepad is running and respond appropriately...

$timer.Add_Tick({
    if ($Label){
        $Label.Text = if (Test-Notepad) { "Notepad is running" } else { "Notepad is NOT running" }
    }
})

You just need to combine them with a couple additional tweaks...

• Store each icon in its own variable with a descriptive name so its easy to switch between them.
• $Main_Tool_Icon needs to be defined outside the scope of create_taskbar_menu so it can be accessed inside of OnMenuItem1ClickEventFn . I moved the creation and initialization to just before the call to create_taskbar_menu , but you could also initialize it inside of create_taskbar_menu or some other function.

That ends up looking like this...

# Choose an icon to display in the systray
$onlineIcon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/online.ico")
# use this icon when notepad is not running
$offlineIcon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/offline.ico")

$Main_Tool_Icon = New-Object System.Windows.Forms.NotifyIcon
$Main_Tool_Icon.Text = "Icon Text"
$Main_Tool_Icon.Icon = if (Test-Notepad) { $onlineIcon } else { $offlineIcon }
$Main_Tool_Icon.Visible = $true

create_taskbar_menu

...and this...

$timer.Add_Tick({
    if ($Label){
        # Change the text and icon with one test
        $Label.Text, $Main_Tool_Icon.Icon = if (Test-Notepad) {
            "Notepad is running", $onlineIcon
        } else {
            "Notepad is NOT running", $offlineIcon
        }
    }
})

You'll see that an icon is selected based on the result of Test-Notepad both when $Main_Tool_Icon is initialized and when the Tick event is raised.

As for disposing $timer when $Form is closing...

$Form.Add_Closing({ $timer.Dispose() })

...that is almost an appropriate place to do that, however...

• The Closing event is raised essentially when the form has been requested to close; it provides an opportunity for that request to be canceled. The Closed event would be more appropriate because it is raised when the form has actually been closed.
• The documentation states that both the Closing and Closed events are obsolete. Use the FormClosed event instead.

Also, in OnMenuItem4ClickEventFn you are calling $window.Close() even though $window is not defined; I think you meant $Form.Close() . An alternative that I think is a bit cleaner would be to have clicking the Exit menu item merely exit the Windows Forms application loop ...

function OnMenuItem4ClickEventFn () {
    $Main_Tool_Icon.Visible = $false

    [System.Windows.Forms.Application]::Exit()
}

...and then you can put your cleanup/teardown code in a finally block at the end of the script...

try
{
    # This call returns when [System.Windows.Forms.Application]::Exit() is called
    [System.Windows.Forms.Application]::Run($appContext)
}
finally
{
    # $timer would also have to be defined at the script scope
    # (outside of OnMenuItem1ClickEventFn) for this to work
    $timer.Dispose()

    # $Form, $Label, $Main_Tool_Icon, $onlineIcon, etc. would all be candidates for disposal...

    # Exit the entire PowerShell process
    Stop-Process $pid
}

---

The following is complete code that incorporates the changes mentioned above and works for me...

Add-Type -AssemblyName System.Windows.Forms    
Add-Type -AssemblyName System.Drawing

function Test-Notepad {
    [bool](Get-Process -Name 'notepad' -ErrorAction SilentlyContinue)
}


function OnMenuItem1ClickEventFn () {
    $timer.Start()

    # Build Form object
    $Form = New-Object System.Windows.Forms.Form
        $Form.Text = "My Form"
        $Form.Size = New-Object System.Drawing.Size(200,200)
        $Form.StartPosition = "CenterScreen"
        $Form.Topmost = $True
        $Form.Add_Closing({ $timer.Dispose() })  # Dispose() also stops the timer.
        $Form.Controls.Add($Label)               # Add label to form
        $form.ShowDialog()| Out-Null             # Show the Form
}


function OnMenuItem4ClickEventFn () {
    $Main_Tool_Icon.Visible = $false

    [System.Windows.Forms.Application]::Exit()
}


function create_taskbar_menu{
    # Create menu items
    $MenuItem1 = New-Object System.Windows.Forms.MenuItem
    $MenuItem1.Text = "Menu Item 1"

    $MenuItem2 = New-Object System.Windows.Forms.MenuItem
    $MenuItem2.Text = "Menu Item 2"

    $MenuItem3 = New-Object System.Windows.Forms.MenuItem
    $MenuItem3.Text = "Menu Item 3"

    $MenuItem4 = New-Object System.Windows.Forms.MenuItem
    $MenuItem4.Text = "Exit"


    # Add menu items to context menu
    $contextmenu = New-Object System.Windows.Forms.ContextMenu
    $Main_Tool_Icon.ContextMenu = $contextmenu
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem1)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem2)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem3)
    $Main_Tool_Icon.contextMenu.MenuItems.AddRange($MenuItem4)


    $MenuItem4.add_Click({OnMenuItem4ClickEventFn})
    $MenuItem1.add_Click({OnMenuItem1ClickEventFn})
}


$Current_Folder = split-path $MyInvocation.MyCommand.Path

# Add assemblies for WPF and Mahapps
[System.Reflection.Assembly]::LoadWithPartialName('System.Windows.Forms')    | out-null
[System.Reflection.Assembly]::LoadWithPartialName('presentationframework')   | out-null
[System.Reflection.Assembly]::LoadWithPartialName('System.Drawing')          | out-null
[System.Reflection.Assembly]::LoadWithPartialName('WindowsFormsIntegration') | out-null
# [System.Reflection.Assembly]::LoadFrom("Current_Folder\assembly\MahApps.Metro.dll")  | out-null

# Choose an icon to display in the systray
$onlineIcon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/online.ico")
# use this icon when notepad is not running
$offlineIcon = [System.Drawing.Icon]::ExtractAssociatedIcon("$Current_Folder/icons/offline.ico")

$Main_Tool_Icon = New-Object System.Windows.Forms.NotifyIcon
$Main_Tool_Icon.Text = "Icon Text"
$Main_Tool_Icon.Icon = if (Test-Notepad) { $onlineIcon } else { $offlineIcon }
$Main_Tool_Icon.Visible = $true

# Build Label object
$Label = New-Object System.Windows.Forms.Label
    $Label.Name = "labelName"
    $Label.AutoSize = $True

# Initialize the timer
$timer = New-Object System.Windows.Forms.Timer
$timer.Interval = 1000
$timer.Add_Tick({
    if ($Label){
        $Label.Text, $Main_Tool_Icon.Icon = if (Test-Notepad) {
            "Notepad is running", $onlineIcon
        } else {
            "Notepad is NOT running", $offlineIcon
        }
    }
})

create_taskbar_menu

# Make PowerShell Disappear - Thanks Chrissy
$windowcode = '[DllImport("user32.dll")] public static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);'
$asyncwindow = Add-Type -MemberDefinition $windowcode -name Win32ShowWindowAsync -namespace Win32Functions -PassThru
$null = $asyncwindow::ShowWindowAsync((Get-Process -PID $pid).MainWindowHandle, 0)

# Use a Garbage colection to reduce Memory RAM
# https://dmitrysotnikov.wordpress.com/2012/02/24/freeing-up-memory-in-powershell-using-garbage-collector/
# https://docs.microsoft.com/fr-fr/dotnet/api/system.gc.collect?view=netframework-4.7.2
[System.GC]::Collect()

# Create an application context for it to all run within - Thanks Chrissy
# This helps with responsiveness, especially when clicking Exit - Thanks Chrissy
$appContext = New-Object System.Windows.Forms.ApplicationContext
try
{
    [System.Windows.Forms.Application]::Run($appContext)    
}
finally
{
    foreach ($component in $timer, $form, $Main_Tool_Icon, $offlineIcon, $onlineIcon, $appContext)
    {
        # The following test returns $false if $component is
        # $null, which is really what we're concerned about
        if ($component -is [System.IDisposable])
        {
            $component.Dispose()
        }
    }

    Stop-Process -Id $PID
}

Answer 2

Hi I know its against the rules to ask more questions here, therefore i asked a follow up questions related to this. Maybe the knowledgeable mr Lance has an answer for me too.. thank you

My Question link