Question

在我的XAML中，有一个按钮和一个标签。启动时，按钮可见，标签不可见。单击install_btn时，标签应变为可见而不是按钮。这是代码的一部分：

private void install_btn_Click(object sender, RoutedEventArgs e)
{
    inst_label.Visibility = Visibility.Visible;
    progress.Visibility = Visibility.Visible;
    install_btn.Visibility = Visibility.Hidden;
}

然后有一些像webClient.DownloadFile()这样的代码。但只有在处理webClient之后，可见性才会切换。如何在下载文件（或其他内容）之前执行切换？

Answer 1

您应该允许应用程序更新它的UI：

private void install_btn_Click(object sender, RoutedEventArgs e)
{
    inst_label.Visibility = Visibility.Visible;
    progress.Visibility = Visibility.Visible;
    install_btn.Visibility = Visibility.Hidden;
    Application.Current.Dispatcher.Invoke(DispatcherPriority.Background, new Action(delegate { }));
    webClient.DownloadFile();
}

可见性切换

1 个答案: