Question

关于SingleInstance class on CodeProject，我有一个棘手的问题。

我希望能够在我的窗口加载之后处理命令行args，在我开始使用SingleInstance之前，我在MainWindow的Loaded事件中处理了所有这些。现在，我想我被迫把所有这些都放在我的App课程中，但我不知道如何从我的ViewModel访问任何属性或方法。

应用代码：

public partial class App : System.Windows.Application, ISingleInstanceApp
{
    public static new App Current
    {
        get {
            return System.Windows.Application.Current as App;
        }
    }
    internal ApplicationInitializeDelegate ApplicationInitialize;
    internal delegate void ApplicationInitializeDelegate(SplashScreen splashWindow);

    private const string Unique = "Unique App Id";

    public bool SignalExternalCommandLineArgs(IList<string> args)
    {
        //This executes for each instance after the first. 
        //We can activate the window and access properties/methods of type Window, 
        //but not of type MainWindow, and, therefore, have no 
        //access to ViewModel.
        this.MainWindow.Activate();
        return true;
    }

    [STAThread]
    public static void Main(params string[] Arguments)
    {
        //Stops new windows from being created.
        if (SingleInstance<App>.InitializeAsFirstInstance(Unique))
        {
            App app = new App();

            app.InitializeComponent();
            app.Run();

            SingleInstance<App>.Cleanup();
        } else {
            //Runs each time after first instance.
        }
    }

    public App()
    {
        ApplicationInitialize = _applicationInitialize;
    }


    //I added this here while experimenting, though, obviously it doesn't do anything yet. Can we do something here, possibly?
    protected override void OnStartup(StartupEventArgs e)
    {
        if (e.Args.Length > 0)
        {
        }
    }

    private void _applicationInitialize(SplashScreen splashWindow)
    {
        //Do work and update splashWindow

        //Create the main window on the UI thread.
        Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(delegate ()
        {
            MainWindow = new MainWindow();
            MainWindow.Show();
        }));
    }
}

修改1

我想出了一个非常肮脏（并不那么理想）的黑客，它给了我我想要的东西，但不是我认为我应该这样做的方式。

public bool SignalExternalCommandLineArgs(IList<string> args)
{
    this.MainWindow.Activate();
    this.MainWindow.Tag = args.Count > 0 ? args[1] : "";
    return true;
}

这允许我直接将我正在尝试执行操作的文件的路径传递给我的MainWindow，以便在加载完所有内容后，我可以继续打开它。我讨厌这个事实，我已经使用了Tag属性，因为它感觉不对。任何替代方案？

处理单实例应用程序中的命令行参数

0 个答案: