双击时，UWP Desktop Bridge应用程序崩溃

Question

I'm working on a UWP Desktop Bridge App. I have created the packaging project and created an app package for sideloading.When I click on the App Icon once, the app launches successfully.But on double click of the Icon, the app crashes.

I have created the packaging project following the link : https://docs.microsoft.com/en-us/windows/msix/desktop/desktop-to-uwp-packaging-dot-net The App runs normally on single click of the app icon. Is it because on double click, the .exe is being invoked twice and that's the reason for the crash?

Here is the Main method of the Background process

   private static void Main(string[] args)
    {
        try
        {
            connection.AppServiceName = "CommunicationService";
            connection.PackageFamilyName = Windows.ApplicationModel.Package.Current.Id.FamilyName;

            // hook up the connection event handlers
            connection.ServiceClosed += Connection_ServiceClosed;
            connection.RequestReceived += Connection_RequestReceived;

            AppServiceConnectionStatus result = AppServiceConnectionStatus.Unknown;


            // static void Main cannot be async until C# 7.1, so put this on the thread pool
            Task.Run(async () =>
            {
                // open a connection to the UWP AppService
                result = await connection.OpenAsync();

            }).GetAwaiter().GetResult();

            if (result == AppServiceConnectionStatus.Success)
            {
                while (true)
                {

                }
            }
        }
        catch (Exception)
        {
        }
    }

The code to call:

    private async Task StartBackgroundProcess()
    {
        try
        {
            // Make sure the BackgroundProcess is in your AppX folder, if not rebuild the solution
            await Windows.ApplicationModel.FullTrustProcessLauncher.LaunchFullTrustProcessForCurrentAppAsync();
        }
        catch (Exception)
        {
            MessageDialog dialog = new MessageDialog("Rebuild the solution and make sure the BackgroundProcess is in your AppX folder");
            await dialog.ShowAsync();
        }
    }

Also,inside package manifest:

<desktop:Extension Category="windows.fullTrustProcess" Executable="BackgroundProcess.exe" />
    <uap:Extension Category="windows.appService">
      <uap:AppService Name="CommunicationService" />
    </uap:Extension>

and

<rescap:Capability Name="runFullTrust" />

Is it possible to avoid the crash issue?

Answer 1

if it's a connection, if you try to connect it twice, it may be crashed. you can make u app only start up once, if it started, then switch to started process.

public partial class App : Application
   {
       /// <summary>
       /// Application Entry Point.
       /// </summary>
       static Mutex muetx = new Mutex(true, "{666666666}");

       [System.STAThreadAttribute()]
       [System.Diagnostics.DebuggerNonUserCodeAttribute()]
       [System.CodeDom.Compiler.GeneratedCodeAttribute("PresentationBuildTasks", "4.0.0.0")]
       public static void Main()
       {
           if (muetx.WaitOne(TimeSpan.Zero, true))
           {
               TestBeginInvoke.App app = new TestBeginInvoke.App();
               app.StartupUri = new Uri("MainWindow.xaml", UriKind.Relative);
               app.Run();
           }
           else
           {
               var pro = System.Diagnostics.Process.GetProcessesByName(nameof(TestBeginInvoke));
               var handle = pro.FirstOrDefault().MainWindowHandle;
               ShowWindow(handle, 1);
               ShowWindow(handle, 9);
               SetForegroundWindow(handle);
           }
       }

       [DllImport("USER32.DLL")]
       public static extern bool SetForegroundWindow(IntPtr hWnd);

       [DllImport("user32.dll")]
       private static extern Boolean ShowWindow(IntPtr hWnd, Int32 nCmdShow);

   }

Answer 2

Please check the AppService Bridge Sample . It creates and starts a separate thread each time to create a new AppServiceConnection instance and call its OpenAsync method.

static void Main(string[] args)
{
    Thread appServiceThread = new Thread(new ThreadStart(ThreadProc));
    appServiceThread.Start();
}

static async void ThreadProc()
{
    connection = new AppServiceConnection();
    connection.AppServiceName = "CommunicationService";
    connection.PackageFamilyName = Windows.ApplicationModel.Package.Current.Id.FamilyName;
    connection.RequestReceived += Connection_RequestReceived;
    AppServiceConnectionStatus status = await connection.OpenAsync();
}