HOWTO: Use the System Tray Directly from Visual Basic
ID: Q176085
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The information in this article applies to:
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Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, version 6.0
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Microsoft Visual Basic Control Creation, Learning, Professional, and Enterprise Editions for Windows, version 5.0
SUMMARY
This article demonstrates how to take full advantage of the Windows System
Tray using Visual Basic. It places an icon of your choice into the
System Tray that will display a ToolTip of your choice when the mouse is
rested over it, will restore the application when clicked, and will display
a popup menu when right-clicked. This is all possible because of Visual
Basic's ability to directly handle callbacks, therefore taking full
advantage of the Shell_NotifyIcon function that is exported by Shell32.dll.
MORE INFORMATION
The following example can be added to any Visual Basic Project that has
at least one form and a standard module.
Step-by-Step Example:
- Add the following code to the declarations section of a standard module
in your project:
'user defined type required by Shell_NotifyIcon API call
Public Type NOTIFYICONDATA
cbSize As Long
hwnd As Long
uId As Long
uFlags As Long
uCallBackMessage As Long
hIcon As Long
szTip As String * 64
End Type
'constants required by Shell_NotifyIcon API call:
Public Const NIM_ADD = &H0
Public Const NIM_MODIFY = &H1
Public Const NIM_DELETE = &H2
Public Const NIF_MESSAGE = &H1
Public Const NIF_ICON = &H2
Public Const NIF_TIP = &H4
Public Const WM_MOUSEMOVE = &H200
Public Const WM_LBUTTONDOWN = &H201 'Button down
Public Const WM_LBUTTONUP = &H202 'Button up
Public Const WM_LBUTTONDBLCLK = &H203 'Double-click
Public Const WM_RBUTTONDOWN = &H204 'Button down
Public Const WM_RBUTTONUP = &H205 'Button up
Public Const WM_RBUTTONDBLCLK = &H206 'Double-click
Public Declare Function SetForegroundWindow Lib "user32" _
(ByVal hwnd As Long) As Long
Public Declare Function Shell_NotifyIcon Lib "shell32" _
Alias "Shell_NotifyIconA" _
(ByVal dwMessage As Long, pnid As NOTIFYICONDATA) As Boolean
Public nid As NOTIFYICONDATA
- Add the following code to any form in your project that you want to
respond to the System Tray Icon for your application:
Private Sub Form_Load()
'the form must be fully visible before calling Shell_NotifyIcon
Me.Show
Me.Refresh
With nid
.cbSize = Len(nid)
.hwnd = Me.hwnd
.uId = vbNull
.uFlags = NIF_ICON Or NIF_TIP Or NIF_MESSAGE
.uCallBackMessage = WM_MOUSEMOVE
.hIcon = Me.Icon
.szTip = "Your ToolTip" & vbNullChar
End With
Shell_NotifyIcon NIM_ADD, nid
End Sub
Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As
_
Single, Y As Single)
'this procedure receives the callbacks from the System Tray icon.
Dim Result As Long
Dim msg As Long
'the value of X will vary depending upon the scalemode setting
If Me.ScaleMode = vbPixels Then
msg = X
Else
msg = X / Screen.TwipsPerPixelX
End If
Select Case msg
Case WM_LBUTTONUP '514 restore form window
Me.WindowState = vbNormal
Result = SetForegroundWindow(Me.hwnd)
Me.Show
Case WM_LBUTTONDBLCLK '515 restore form window
Me.WindowState = vbNormal
Result = SetForegroundWindow(Me.hwnd)
Me.Show
Case WM_RBUTTONUP '517 display popup menu
Result = SetForegroundWindow(Me.hwnd)
Me.PopupMenu Me.mPopupSys
End Select
End Sub
Private Sub Form_Resize()
'this is necessary to assure that the minimized window is hidden
If Me.WindowState = vbMinimized Then Me.Hide
End Sub
Private Sub Form_Unload(Cancel As Integer)
'this removes the icon from the system tray
Shell_NotifyIcon NIM_DELETE, nid
End Sub
Private Sub mPopExit_Click()
'called when user clicks the popup menu Exit command
Unload Me
End Sub
Private Sub mPopRestore_Click()
'called when the user clicks the popup menu Restore command
Me.WindowState = vbNormal
Result = SetForegroundWindow(Me.hwnd)
Me.Show
End Sub
- Make the following Property Settings on the same form to which you added
the above code:
Property Required Setting for System Tray example
---------------------------------------------------------------
Icon = The icon you want to appear in the system tray.
Minbutton = True
ShownInTaskbar = False
- Add the following Menu items to the same form using the Menu Editor:
Caption Name Enabled Visible Position
---------------------------------------------------------
&SysTray mPopupSys True False Main Level
&Restore mPopRestore True True Inset one
&Exit mPopExit True True Inset one
You can add additional menu items as needed.
System Tray Flexibility
You can modify the ToolTip that appears over the System Tray icon by
changing the following line in the Form_Load procedure:
.szTip = "Your ToolTip" & vbNullChar
Replace "Your ToolTip" with the text that you want to appear.
You can modify the Icon that appears in the System Tray by changing the
following line in the Form_Load procedure:
.hIcon = Me.Icon
Replace Me.Icon with any Icon in your project.
You can change any of the System Trays settings at any time after the use
of the NIM_ADD constant by reassigning the values in the nid variable and
then using the following variation of the Shell_NotifyIcon API call:
Shell_NotifyIcon NIM_MODIFY, nid.
However, if you want a different form to receive the callback, then you
will need to delete the current icon first using "Shell_NotifyIcon
NIM_Delete, nid" as the NIM_Modify function will not accept a new Hwnd, or
you will need to add another Icon to the systray for the new form using
"Shell_NotifyIcon NIM_ADD, nid" after refilling the nid type with the new
forms Hwnd. You can also declare separate copies of the nid type for each
form that you want to display an icon for in the Windows System Tray and
change them in each form's activate event using the NIM_DELETE and NIM_ADD
sequence.
REFERENCES
For information regarding using the System Tray from Visual Basic 4.0 or
earlier, please see the following article in the Microsoft Knowledge Base:
Q149276 HOWTO: Use Icons with the Windows 95 System Tray
Additional query words:
Taskbar kbVBp500 kbVBp600 kbdse kbDSupport kbVBp kbVBp400
Keywords : kbGrpVBDB
Version :
Platform : WINDOWS
Issue type : kbhowto
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