Fix bug where StartLoop could run multiple times

README.md

@@ -86,7 +86,7 @@ _sparkle = new SparkleUpdater(
 ) {
     UIFactory = new NetSparkleUpdater.UI.WPF.UIFactory(icon) // or null or choose some other UI factory or build your own!
 };
-_sparkle.StartLoop(true); // `true` to run an initial check online
+_sparkle.StartLoop(true); // `true` to run an initial check online -- only call StartLoop once for a given SparkleUpdater instance!
 ```
 
 On the first Application.Idle event, your App Cast XML file will be downloaded, read, and compared to the currently running version. If it has a software update inside, the user will be notified with a little toast notification (if supported by the UI and enabled) or with an update dialog containing your release notes. The user can then ignore the update, ask to be reminded later, or download/install it now.

nuget/tools/NetSparkleUpdater.Tools.nuspec

@@ -3,7 +3,7 @@
  <metadata>
    <id>NetSparkleUpdater.Tools</id>
    <title>NetSparkleUpdater Tools</title>
-   <version>2.0.0-preview20200514006</version>
+   <version>2.0.0-preview20200604001</version>
    <authors>Deadpikle, Dirk Eisenberg</authors>
    <owners>Deadpikle</owners>
    <license type="file">LICENSE.md</license>

nuget/winformsnetframework/NetSparkleUpdater.UI.WinForms.NetFramework.nuspec

@@ -3,7 +3,7 @@
  <metadata>
    <id>NetSparkleUpdater.UI.WinForms.NetFramework</id>
    <title>NetSparkleUpdater WinForms .NET Framework UI</title>
-   <version>2.0.0-preview20200514006</version>
+   <version>2.0.0-preview20200604001</version>
    <authors>Deadpikle, Dirk Eisenberg</authors>
    <owners>Deadpikle</owners>
    <license type="file">LICENSE.md</license>
@@ -19,7 +19,7 @@
    <releaseNotes>2.0 Beta: See https://github.com/NetSparkleUpdater/NetSparkle for all beta information and to file issues/pull requests for and ask questions about this project.</releaseNotes>
     <dependencies>
       <group targetFramework=".NETFramework4.5.1">
-        <dependency id="NetSparkle.New" version="2.0.0-preview20200514006" exclude="Build,Analyzers" />
+        <dependency id="NetSparkle.New" version="2.0.0-preview20200604001" exclude="Build,Analyzers" />
       </group>
     </dependencies>
  </metadata>

src/NetSparkle.UI.Avalonia/NetSparkle.UI.Avalonia.csproj

@@ -4,7 +4,7 @@
     <TargetFramework>netcoreapp3.1</TargetFramework>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <PackageId>NetSparkleUpdater.UI.Avalonia</PackageId>
-    <Version>2.0.0-preview20200514006</Version>
+    <Version>2.0.0-preview20200604001</Version>
     <Authors>Deadpikle</Authors>
     <Company>Deadpikle</Company>
     <Product>NetSparkleUpdater.UI.Avalonia</Product>

src/NetSparkle.UI.WPF/NetSparkle.UI.WPF.csproj

@@ -14,7 +14,7 @@
     <RepositoryUrl>https://github.com/NetSparkleUpdater/NetSparkle.git</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
     <AssemblyVersion>2.0.0.0</AssemblyVersion>
-    <Version>2.0.0-preview20200514006</Version>
+    <Version>2.0.0-preview20200604001</Version>
     <PackageIcon>software-update-available.png</PackageIcon>
     <PackageIconUrl />
     <Description>NetSparkleUpdater/NetSparkle app updater framework with built-in WPF .NET Core UI. NetSparkleUpdater/NetSparkle is a C# .NET software update framework that allows you to easily download installer files and update your C# .NET Framework or .NET Core software. Built-in UIs are available for WinForms, WPF, and Avalonia. You provide, somewhere on the internet, an XML appcast with software version information along with release notes in Markdown or HTML format. The NetSparkle framework then checks for an update in the background, displays the release notes to the user, and lets users download or skip the software update. The framework can also perform silent downloads so that you can present all of the UI yourself or set up your own silent software update system, as allowed by your software architecture. It was inspired by the Sparkle (https://sparkle-project.org/) project for Cocoa developers and the WinSparkle (https://winsparkle.org/) project (a Win32 port).</Description>

src/NetSparkle.UI.WinForms.NetCore/NetSparkle.UI.WinForms.NetCore.csproj

@@ -10,7 +10,7 @@
     <Copyright>Copyright © 2020</Copyright>
     <OutputPath>..\bin\$(Configuration)\NetSparkle.UI.WinForms\</OutputPath>
     <PackageId>NetSparkleUpdater.UI.WinForms.NetCore</PackageId>
-    <Version>2.0.0-preview20200514006</Version>
+    <Version>2.0.0-preview20200604001</Version>
     <Authors>Deadpikle</Authors>
     <Company>Deadpikle</Company>
     <Description>NetSparkleUpdater/NetSparkle app updater framework with built-in WinForms .NET Core UI. NetSparkleUpdater/NetSparkle is a C# .NET software update framework that allows you to easily download installer files and update your C# .NET Framework or .NET Core software. Built-in UIs are available for WinForms, WPF, and Avalonia. You provide, somewhere on the internet, an XML appcast with software version information along with release notes in Markdown or HTML format. The NetSparkle framework then checks for an update in the background, displays the release notes to the user, and lets users download or skip the software update. The framework can also perform silent downloads so that you can present all of the UI yourself or set up your own silent software update system, as allowed by your software architecture. It was inspired by the Sparkle (https://sparkle-project.org/) project for Cocoa developers and the WinSparkle (https://winsparkle.org/) project (a Win32 port).</Description>

src/NetSparkle/NetSparkle.cs

@@ -443,7 +443,12 @@ public async void StartLoop(bool doInitialCheck, bool forceInitialCheck, TimeSpa
             // start the work
             //var scheduler = TaskScheduler.FromCurrentSynchronizationContext();
             //_taskWorker.Start(scheduler);
-            _taskWorker.Start();
+            // don't allow starting the task 2x
+            if (_taskWorker.IsCompleted == false && _taskWorker.Status != TaskStatus.Running && 
+                _taskWorker.Status != TaskStatus.WaitingToRun && _taskWorker.Status != TaskStatus.WaitingForActivation)
+            {
+                _taskWorker.Start();
+            }
         }
 
         /// <summary>

src/NetSparkle/NetSparkle.csproj

@@ -4,7 +4,7 @@
     <TargetFrameworks>netstandard2.0;net451</TargetFrameworks>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <PackageId>NetSparkle.New</PackageId>
-    <Version>2.0.0-preview20200514006</Version>
+    <Version>2.0.0-preview20200604001</Version>
     <Authors>Deadpikle, Dirk Eisenberg</Authors>
     <Description>NetSparkleUpdater/NetSparkle is a C# .NET software update framework that allows you to easily download installer files and update your C# .NET Framework or .NET Core software. Built-in UIs are available for WinForms, WPF, and Avalonia. You provide, somewhere on the internet, an XML appcast with software version information along with release notes in Markdown or HTML format. The NetSparkle framework then checks for an update in the background, displays the release notes to the user, and lets users download or skip the software update. The framework can also perform silent downloads so that you can present all of the UI yourself or set up your own silent software update system, as allowed by your software architecture. It was inspired by the Sparkle (https://sparkle-project.org/) project for Cocoa developers and the WinSparkle (https://winsparkle.org/) project (a Win32 port).</Description>
     <Copyright>Copyright 2010 - 2020</Copyright>