Private Declare Function Shell_NotifyIcon Lib "shell32.dll" _
 Alias "Shell_NotifyIconA" (ByVal dwMessage As Long, _
 lpData As NOTIFYICONDATA) As Long
 
Private 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
 
Private Const NIF_ICON = &H2
Private Const NIF_MESSAGE = &H1
Private Const NIF_TIP = &H4
Private Const NIM_ADD = &H0
Private Const NIM_DELETE = &H2
Private Const NIM_MODIFY = &H1
 
Dim IC As NOTIFYICONDATA
 
Private Sub ShowIconInTray(add As Boolean)
  With IC
   .cbSize = Len(IC)
   .hwnd = Me.hwnd 'Nachrichten-Fenster
   .uID = 2& 'unveränderlich
   .uFlags = NIF_MESSAGE Or NIF_ICON Or NIF_TIP
   .uCallbackMessage = &H200 'Auswertung in MouseMove
   .hIcon = Me.Icon    'anzuzeigendes Icon
   .szTip = "Das ist der Tooltip" + vbNullChar
  End With
  If add = True Then
    Shell_NotifyIcon NIM_ADD, IC
  Else
    Shell_NotifyIcon NIM_DELETE, IC
  End If
End Sub
 
Private Sub Command1_Click()
  Me.Hide
  ShowIconInTray True
End Sub
 
Private Sub Form_MouseMove(Button As Integer, _
Shift As Integer, X As Single, Y As Single)
  'Hier erfolgt die Auswertung
  Select Case Button
   Case 2
     'rechte Maustaste gedrückt
   Case 1
     'linke Maustaste gedrückt
     ShowIconInTray False
     Me.Visible = True
  End Select
End Sub

mfg
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