判断窗口活动状态解决方案

判断窗口活动状态
窗口活动时窗口背景色为红色，不活动时窗口背景色为灰色:

Private   Sub   Form_Load()
  bCancel   =   False
Me.Visible   =   True
  ProcessWindow
End   Sub

Private   Sub   Form_Unload(Cancel   As   Integer)
bCancel   =   True
End   Sub
Private   Sub   ProcessWindow()
  Do   While   Not   bCancel
  n   =   IsWindowEnabled(Me.hwnd)
  If   n   <>   0   Then
        Me.BackColor   =   vbRed
        Else
        Me.BackColor   =   &H8000000F
End   If
DoEvents
Loop
End   Sub
结果无效..
请说明原因,谢谢

[解决办法]
GetActiveWindow
GetForegroundWindow
用这两个API