Question

我有一个MDI容器，而且我使用了自己的自定义类MsgBox（称为ShowMsg），该类主要在子窗体上使用，到目前为止，它工作得很好，直到我意识到Showmsg（这是一个ShowDialog）没有坚持到父表单（MDIContainer）。

在子窗体中，如果用户在进程运行并完成时使用alt + tab切换到另一个程序，并且用户使用Alt +返回到我的应用程序，则我使用线程来运行进程并显示进度栏Tab，ShowMsg不在那里，它消失了，我无能为力，无法恢复它，所以我的应用程序变得无用了。

仅当从与Form本身不同的线程中调用它时，才会发生这种情况，我正在拔头发，为什么消失了？？

这是代码的一部分：


parser.add_argument('infile', metavar="INFILE", nargs='?',
                    type=argparse.FileType('r'),
                    action='append', dest="positional_args")
parser.add_argument('outfile', metavar="OUTFILE", nargs='?', 
                    type=argparse.FileType('w'),
                    action='append', dest="positional_args")
parser.add_argument('-i', metavar="INFILE", dest="infile", default=None)
parser.add_argument('-o', metavar="OUTFILE", dest="outfile", default=None)

args = parser.parse_args([....])

# here insert check for conflicts between len(args.positional_args) and -i and -o
# example:
if sum([len(args.positional_args),
       args.infile is not None,
       args.outfile is not None]) != 2:
   parser.print_help()
   sys.exit(1)
...

infile = args.infile or args.positional_args.pop(0)
outfile = args.outfile or args.positional_args.pop(0)

在孩子身上的样本：

Public Function ShowMsg(ByVal Text As String, ByVal Icon As ShowMsgImage, ByVal Title As String) As DialogResult
    Dim SMF As New ShowMsgForm

    'Set the title bar
    SMF.Text = Title

    'Select an image and sound based on the Icon parameter
    Select Case Icon
        Case ShowMsgImage.Alert
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_Warning
            SMF.Sound = Media.SystemSounds.Asterisk
        Case ShowMsgImage.Confirm
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_Confirm
            SMF.Sound = Media.SystemSounds.Question
        Case ShowMsgImage.Critical
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_NotAllowed
            SMF.Sound = Media.SystemSounds.Hand
        Case ShowMsgImage.Info
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_Info
            SMF.Sound = Media.SystemSounds.Asterisk
        Case ShowMsgImage.Security
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_Lock
            SMF.Sound = Media.SystemSounds.Beep
        Case ShowMsgImage.UnderConstruction
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_NotAllowed
            SMF.Sound = Media.SystemSounds.Asterisk
        Case ShowMsgImage.Ok
            SMF.MessagePictureBox.Image = My.Resources.ico_showmsg_ok
            SMF.Sound = Media.SystemSounds.Asterisk
    End Select

    'Set other properties
    SMF.TextLabel.Text = Text
    SMF.QuestionTextLabel.Text = ""
    SMF.Button1.Visible = True
    SMF.Button1.Text = "OK"
    SMF.Button1.DialogResult = DialogResult.OK
    SMF.Button2.Visible = False
    SMF.Button3.Visible = False

    'Resize the form
    SMF.SizeForm()

    'Set its starting position
    SMF.StartPosition = FormStartPosition.CenterScreen

    'Display the form modally and return its DialogResult
    Try
        Return SMF.ShowDialog()
    Catch ex As Exception

    End Try


End Function

Answer 1

经过几天的测试，我认为我找到了答案。

我添加了：

TopLevel = True，显示时

参数父母表格

        SMF.TopLevel = True
        Return SMF.ShowDialog(**frm**)

frm是调用ShowMsg的形式

使用Alt + Tab时Showdialog消失

1 个答案: