Fix Wox restart by wait Mutex to be released

Fix bug in 24866ff032829e9bd34704d3d5970d227a4c8db3.
Wait existing Mutex to release itself instead of create a new one.
Relate issue: #322

Wox/App.xaml.cs

@@ -50,14 +50,16 @@ namespace Wox
             AppDomain.CurrentDomain.UnhandledException += ErrorReporting.UnhandledExceptionHandle;
         }
 
-        public bool OnActivate(IList<string> args)
+        public void OnActivate(IList<string> args)
         {
             if (args.Count > 0 && args[0] == SingleInstance<App>.Restart)
             {
                 Window.CloseApp();
             }
+            else
+            {
                 CommandArgsFactory.Execute(args);
-            return true;
+            }
         }
     }
 }

Wox/Helper/SingleInstance.cs

@@ -1,14 +1,4 @@
-//-----------------------------------------------------------------------
-// <copyright file="SingleInstance.cs" company="Microsoft">
-//     Copyright (c) Microsoft Corporation.  All rights reserved.
-// </copyright>
-// <summary>
-//     This class checks to make sure that only one instance of 
-//     this application is running at a time.
-// </summary>
-//-----------------------------------------------------------------------
-
-using System;
+using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.ComponentModel;
@@ -23,7 +13,8 @@ using System.Threading;
 using System.Windows;
 using System.Windows.Threading;
 
-//http://blogs.microsoft.co.il/arik/2010/05/28/wpf-single-instance-application/
+// http://blogs.microsoft.co.il/arik/2010/05/28/wpf-single-instance-application/
+// modified to allow single instace restart
 namespace Wox.Helper 
 {
     internal enum WM
@@ -194,7 +185,7 @@ namespace Wox.Helper
 
     public interface ISingleInstanceApp 
     { 
-         bool OnActivate(IList<string> args); 
+         void OnActivate(IList<string> args); 
     } 
 
     /// <summary>
@@ -239,7 +230,7 @@ namespace Wox.Helper
         /// <summary>
         /// Application mutex.
         /// </summary>
-        private static Mutex singleInstanceMutex;
+        internal static Mutex singleInstanceMutex;
 
         /// <summary>
         /// IPC channel for communications.
@@ -291,10 +282,11 @@ namespace Wox.Helper
                 CreateRemoteService(channelName);
                 return true;
             }
+            // Restart
             else if (commandLineArgs.Count > 0 && commandLineArgs[0] == Restart)
             {
                 SignalFirstInstance(channelName, commandLineArgs);
-                singleInstanceMutex = new Mutex(true, applicationIdentifier);
+                singleInstanceMutex.WaitOne(TimeSpan.FromSeconds(10));
                 CreateRemoteService(channelName);
                 return true;
             }

Wox/MainWindow.xaml.cs

@@ -80,12 +80,8 @@ namespace Wox
 
         public void CloseApp()
         {
-            Dispatcher.Invoke(new Action(() =>
-            {
-                notifyIcon.Visible = false;
-                Close();
-                Environment.Exit(0);
-            }));
+            SingleInstance<App>.singleInstanceMutex.ReleaseMutex();
+            Application.Current.Shutdown();
         }
 
         public void RestarApp()

Wox/Wox.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
   <PropertyGroup>