窗体无法获得焦点

Option Compare Database

Private Sub Form_Close()
forms = FindWindow(vbNullString, "主界面")
Call MyShow(1, 1)
'SetActiveWindows Application.hWndAccessApp
'SetFocusAPI (froms)

End Sub

Private Sub Form_Open(Cancel As Integer)
    DoCmd.Maximize
    ' 隐藏主窗体 , 显示子窗体到标题栏
    forms = Me.hwnd
    Call MyShow(1, 1)
    ShowWindow Application.hWndAccessApp, SW_HIDE
  
End Sub

Private Sub 退出系统_Click()
    DoCmd.Close
   
End Sub

以上是B窗体的代码