[One .NET] dotnet new project and item templates

Context: https://docs.microsoft.com/dotnet/core/tutorials/cli-templates-create-template-pack
Context: https://github.com/dotnet/templating/wiki
Context: dotnet/designs#120

This implements basic Android templates that are contained in a
`Microsoft.Android.Templates.nupkg` file.

We can define a template pack in `WorkloadManifest.json`:

    "Microsoft.Android.Templates": {
      "kind": "template",
      "version": "@TEMPLATE_PACK_VERSION@"
    }

This allows the workload to locate the `*.nupkg` file in:

    C:\Program Files\dotnet\template-packs
    /usr/local/share/dotnet/template-packs

Our .NET 6 preview installers simply have to place the `*.nupkg` files
in the right place for them to be picked up by `dotnet new`.

Some example project templates:

    dotnet new android            --output MyAndroidApp     --packageName com.mycompany.myandroidapp
    dotnet new androidlib         --output MyAndroidLibrary
    dotnet new android-bindinglib --output MyJavaBinding

And item templates:

    dotnet new android-activity --name LoginActivity --namespace MyAndroidApp
    dotnet new android-layout   --name MyLayout      --output Resources/layout

Note that the `android-bindinglib` template is not a special project
type. It has additional help files for writing bindings as we have in
the current Xamarin.Android templates.

I also updated the `XASdkTests` to `dotnet new` each template and
`dotnet build` the resulting output.

Author: jonathanpeppers

Documentation/guides/OneDotNet.md

@@ -189,12 +189,45 @@ It is recommended to migrate to the new linker settings, as
 There are currently a few "verbs" we are aiming to get working in
 Xamarin.Android:
 
+    dotnet new
     dotnet build
     dotnet publish
     dotnet run
 
-Currently in .NET 5 console apps, `dotnet publish` is where all the
-work to produce a self-contained "app" happens:
+### dotnet new
+
+To support `dotnet new`, we created a few basic project and item
+templates for Android that are named following the patterns and naming
+of existing .NET templates:
+
+    Templates                                     Short Name           Language    Tags
+    --------------------------------------------  -------------------  ----------  ----------------------
+    Android Activity template                     android-activity     [C#]        Android
+    Android Java Library Binding                  android-bindinglib   [C#]        Android
+    Android Layout template                       android-layout       [C#]        Android
+    Android Class library                         androidlib           [C#]        Android
+    Android Application                           android              [C#]        Android
+    Console Application                           console              [C#],F#,VB  Common/Console
+    Class library                                 classlib             [C#],F#,VB  Common/Library
+    Razor Page                                    page                 [C#]        Web/ASP.NET
+    ASP.NET Core Web App                          webapp               [C#]        Web/MVC/Razor Pages
+
+To create different types of Android projects:
+
+    dotnet new android            --output MyAndroidApp     --packageName com.mycompany.myandroidapp
+    dotnet new androidlib         --output MyAndroidLibrary
+    dotnet new android-bindinglib --output MyJavaBinding
+
+Once the projects are created, some basic item templates can also be
+used such as:
+
+    dotnet new android-activity --name LoginActivity --namespace MyAndroidApp
+    dotnet new android-layout   --name MyLayout      --output Resources/layout
+
+### dotnet build & publish
+
+Currently in .NET console apps, `dotnet publish` is where all the work
+to produce a self-contained "app" happens:
 
 * The linker via the `<IlLink/>` MSBuild task
 * .NET Core's version of AOT, named "ReadyToRun"
@@ -223,12 +256,18 @@ Play, ad-hoc distribution, etc. It could be able to sign the `.apk` or
 `.aab` with different keys. As a starting point, this will currently
 copy the output to a `publish` directory on disk.
 
+[illink]: https://github.com/mono/linker/blob/master/src/linker/README.md
+
+### dotnet run
+
 `dotnet run` can be used to launch applications on a
 device or emulator via the `--project` switch:
 
     dotnet run --project HelloAndroid.csproj
 
-[illink]: https://github.com/mono/linker/blob/master/src/linker/README.md
+Alternatively, you could use the `Run` MSBuild target such as:
+
+    dotnet build HelloAndroid.csproj -t:Run
 
 ### Preview testing
 

build-tools/Xamarin.Android.Tools.BootstrapTasks/Xamarin.Android.Tools.BootstrapTasks/GenerateWixFile.cs

@@ -108,9 +108,22 @@ public override bool Execute ()
 				packWriter.WriteStartElement ("Directory");
 				packWriter.WriteAttributeString ("Id", "packs");
 				packWriter.WriteAttributeString ("Name", "packs");
+				packWriter.WriteAttributeString ("FileSource", packs_dir);
 				foreach (var directory in Directory.EnumerateDirectories (packs_dir, "Microsoft.Android.*")) {
 					RecurseDirectory (packs_dir, packWriter, componentWriter, directory);
 				}
+				packWriter.WriteEndElement (); // </Directory> packs
+
+				// template-packs
+				var templates_dir = Path.Combine (DotNetPath, "template-packs");
+				packWriter.WriteStartElement ("Directory");
+				packWriter.WriteAttributeString ("Id", "templatepacks");
+				packWriter.WriteAttributeString ("Name", "template-packs");
+				packWriter.WriteAttributeString ("FileSource", templates_dir);
+				foreach (var file in Directory.EnumerateFiles (templates_dir, "Microsoft.Android.Templates.*.nupkg")) {
+					AddFile (templates_dir, packWriter, componentWriter, file);
+				}
+				packWriter.WriteEndElement (); // </Directory> template-packs
 
 				packWriter.WriteEndDocument (); // </Directory>
 				componentWriter.WriteEndDocument (); // </ComponentGroup>
@@ -145,22 +158,27 @@ static void RecurseDirectory (string top_dir, XmlWriter packWriter, XmlWriter co
 				var fileName = Path.GetFileName (file);
 				if (fileName.StartsWith (".") || fileName.StartsWith ("_"))
 					continue;
-				var componentId = GetId (top_dir, file);
-				packWriter.WriteStartElement ("Component");
-				packWriter.WriteAttributeString ("Id", componentId);
-				packWriter.WriteStartElement ("File");
-				packWriter.WriteAttributeString ("Id", componentId);
-				packWriter.WriteAttributeString ("Name", Path.GetFileName (file));
-				packWriter.WriteAttributeString ("KeyPath", "yes");
-				packWriter.WriteEndElement (); // </File>
-				packWriter.WriteEndElement (); // </Component>
-				componentWriter.WriteStartElement ("ComponentRef");
-				componentWriter.WriteAttributeString ("Id", componentId);
-				componentWriter.WriteEndElement (); // </ComponentRef>
+				AddFile (top_dir, packWriter, componentWriter, file);
 			}
 			packWriter.WriteEndElement (); // </Directory>
 		}
 
+		static void AddFile (string top_dir, XmlWriter packWriter, XmlWriter componentWriter, string file)
+		{
+			string componentId = GetId (top_dir, file);
+			packWriter.WriteStartElement ("Component");
+			packWriter.WriteAttributeString ("Id", componentId);
+			packWriter.WriteStartElement ("File");
+			packWriter.WriteAttributeString ("Id", componentId);
+			packWriter.WriteAttributeString ("Name", Path.GetFileName (file));
+			packWriter.WriteAttributeString ("KeyPath", "yes");
+			packWriter.WriteEndElement (); // </File>
+			packWriter.WriteEndElement (); // </Component>
+			componentWriter.WriteStartElement ("ComponentRef");
+			componentWriter.WriteAttributeString ("Id", componentId);
+			componentWriter.WriteEndElement (); // </ComponentRef>
+		}
+
 		static string GetId (string top_dir, string path)
 		{
 			if (string.IsNullOrEmpty (path))

build-tools/create-dotnet-pkg/create-dotnet-pkg.csproj

@@ -35,6 +35,7 @@
       <_FilesToCopy Include="$(DotNetPreviewPath)\sdk-manifests\$(DotNetPreviewVersionBand)\Microsoft.NET.Workload.Android\**\*" />
       <_FilesToCopy Include="$(DotNetPreviewPath)\packs\Microsoft.Android.Ref\**\*" />
       <_FilesToCopy Include="$(DotNetPreviewPath)\packs\Microsoft.Android.Sdk.osx-x64\**\*" />
+      <_FilesToCopy Include="$(DotNetPreviewPath)\template-packs\Microsoft.Android.Templates.*.nupkg" />
     </ItemGroup>
     <MakeDir Directories="$(PkgOutputPath);$(PayloadDir);$(PkgResourcesPath);$(LicenseDestination)"/>
     <ReplaceFileContents

build-tools/create-packs/Directory.Build.targets

@@ -82,6 +82,7 @@
     <Exec Command="$(DotNetPreviewTool) pack @(_GlobalProperties, ' ') -p:AndroidHostRID=osx-x64   &quot;$(MSBuildThisFileDirectory)Microsoft.Android.Sdk.proj&quot;"     Condition=" '$(HostOS)' == 'Darwin' " />
     <Exec Command="$(DotNetPreviewTool) pack @(_GlobalProperties, ' ') -p:AndroidHostRID=win-x64   &quot;$(MSBuildThisFileDirectory)Microsoft.Android.Sdk.proj&quot;" Condition=" '$(HostOS)' != 'Linux' " /> <!-- Windows pack should be built both Windows and macOS -->
     <Exec Command="$(DotNetPreviewTool) pack @(_GlobalProperties, ' ') &quot;$(MSBuildThisFileDirectory)Microsoft.NET.Workload.Android.proj&quot;" />
+    <Exec Command="$(DotNetPreviewTool) pack @(_GlobalProperties, ' ') &quot;$(XamarinAndroidSourcePath)src\templates\templates.csproj&quot;" />
   </Target>
 
   <Target Name="ExtractWorkloadPacks"
@@ -92,6 +93,7 @@
       <_WLPacks Include="$(XamarinAndroidSourcePath)bin\Build$(Configuration)\nupkgs\Microsoft.Android.Sdk.osx-x64.*.nupkg"     Condition=" '$(HostOS)' == 'Darwin' " />
       <_WLPacks Include="$(XamarinAndroidSourcePath)bin\Build$(Configuration)\nupkgs\Microsoft.Android.Sdk.win-x64.*.nupkg" Condition=" '$(HostOS)' == 'Windows' " />
       <_WLPacks Include="$(XamarinAndroidSourcePath)bin\Build$(Configuration)\nupkgs\Microsoft.Android.Ref.*.nupkg" />
+      <_WLTemplates Include="$(XamarinAndroidSourcePath)bin\Build$(Configuration)\nupkgs\Microsoft.Android.Templates.*.nupkg" />
       <!-- Runtime packs are not yet supported by workloads -->
       <!-- <_WLPacks Include="$(XamarinAndroidSourcePath)bin\Build$(Configuration)\nupkgs\Microsoft.Android.Runtime.*.nupkg" /> -->
     </ItemGroup>
@@ -106,6 +108,8 @@
         SourceFiles="@(_WLPacks)"
         DestinationFolder="$(DotNetPreviewPath)packs\$([System.String]::Copy('%(_WLPacks.Filename)').Replace('.$(_WLPackVersion)', ''))\$(_WLPackVersion)"
     />
+    <MakeDir Directories="$(DotNetPreviewPath)template-packs" />
+    <Copy SourceFiles="@(_WLTemplates)" DestinationFolder="$(DotNetPreviewPath)template-packs" />
     <ItemGroup>
       <_UnixExecutables Include="$(DotNetPreviewPath)packs\Microsoft.Android.Sdk.*\*\tools\$(HostOS)\**\*.*" />
       <_FilesToTouch Include="$(DotNetPreviewPath)sdk-manifests\$(DotNetPreviewVersionBand)\Microsoft.NET.Workload.Android\**" />
@@ -129,6 +133,7 @@
       <_PackFilesToDelete Include="$(DotNetPreviewPath)sdk-manifests\$(DotNetPreviewVersionBand)\Microsoft.Android.Workload\**\*.*" />
       <_PackFilesToDelete Include="$(DotNetPreviewPath)sdk-manifests\$(DotNetPreviewVersionBand)\Microsoft.NET.Workload.Android\**\*.*" />
       <_PackFilesToDelete Include="$(DotNetPreviewPath)packs\Microsoft.Android*\**\*.*" />
+      <_PackFilesToDelete Include="$(DotNetPreviewPath)template-packs\Microsoft.Android.Templates.*.nupkg" />
     </ItemGroup>
     <RemoveDir Directories="%(_PackFilesToDelete.RootDir)%(_PackFilesToDelete.Directory)" />
     <Delete Files="$(_WorkloadResolverFlagFile)" />

build-tools/create-packs/Microsoft.NET.Workload.Android.proj

@@ -36,7 +36,7 @@ workload manifest pack containing information about the various Microsoft.Androi
     <ReplaceFileContents
         SourceFile="$(XamarinAndroidSourcePath)src\Xamarin.Android.Build.Tasks\Microsoft.NET.Workload.Android\WorkloadManifest.in.json"
         DestinationFile="$(WorkloadManifestJsonPath)"
-        Replacements="@SDK_PACK_VERSION@=$(AndroidPackVersionLong);@REF_PACK_VERSION@=$(AndroidPackVersionLong)">
+        Replacements="@SDK_PACK_VERSION@=$(AndroidPackVersionLong);@REF_PACK_VERSION@=$(AndroidPackVersionLong);@TEMPLATE_PACK_VERSION@=$(AndroidPackVersionLong);">
     </ReplaceFileContents>
 
     <ItemGroup>

src/Xamarin.Android.Build.Tasks/Microsoft.NET.Workload.Android/WorkloadManifest.in.json

@@ -5,7 +5,8 @@
       "description": "Android SDK",
       "packs": [
         "Microsoft.Android.Sdk",
-        "Microsoft.Android.Ref"
+        "Microsoft.Android.Ref",
+        "Microsoft.Android.Templates"
       ]
     }
   },
@@ -21,6 +22,10 @@
     "Microsoft.Android.Ref": {
       "kind": "framework",
       "version": "@REF_PACK_VERSION@"
+    },
+    "Microsoft.Android.Templates": {
+      "kind": "template",
+      "version": "@TEMPLATE_PACK_VERSION@"
     }
   }
 }

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/XASdkTests.cs

@@ -177,6 +177,16 @@ public void DotNetBuildLibrary (bool isRelease, bool duplicateAar)
 			StringAssert.Contains ("public const int MyLayout", resource_designer_text);
 		}
 
+		[Test]
+		public void DotNetNew ([Values ("android", "androidlib", "android-bindinglib")] string template)
+		{
+			var dotnet = CreateDotNetBuilder ();
+			Assert.IsTrue (dotnet.New (template), $"`dotnet new {template}` should succeed");
+			Assert.IsTrue (dotnet.New ("android-activity"), "`dotnet new android-activity` should succeed");
+			Assert.IsTrue (dotnet.New ("android-layout", Path.Combine (dotnet.ProjectDirectory, "Resources", "layout")), "`dotnet new android-layout` should succeed");
+			Assert.IsTrue (dotnet.Build (), "`dotnet build` should succeed");
+		}
+
 		[Test]
 		public void DotNetPack ([Values ("net6.0-android", "net6.0-android30")] string targetFramework)
 		{
@@ -461,6 +471,16 @@ void CreateEmptyFile (params string [] paths)
 			}
 		}
 
+		DotNetCLI CreateDotNetBuilder (string relativeProjectDir = null)
+		{
+			if (string.IsNullOrEmpty (relativeProjectDir)) {
+				relativeProjectDir = Path.Combine ("temp", TestName);
+			}
+			TestOutputDirectories [TestContext.CurrentContext.Test.ID] =
+				FullProjectDirectory = Path.Combine (Root, relativeProjectDir);
+			return new DotNetCLI (Path.Combine (FullProjectDirectory, $"{TestName}.csproj"));
+		}
+
 		DotNetCLI CreateDotNetBuilder (XASdkProject project, string relativeProjectDir = null)
 		{
 			if (string.IsNullOrEmpty (relativeProjectDir)) {

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.ProjectTools/Common/DotNetCLI.cs

@@ -21,13 +21,18 @@ public class DotNetCLI
 		readonly XASdkProject project;
 		readonly string projectOrSolution;
 
-		public DotNetCLI (XASdkProject project, string projectOrSolution)
+		public DotNetCLI (string projectOrSolution)
 		{
-			this.project = project;
 			this.projectOrSolution = projectOrSolution;
 			ProjectDirectory = Path.GetDirectoryName (projectOrSolution);
 		}
 
+		public DotNetCLI (XASdkProject project, string projectOrSolution)
+			: this (projectOrSolution)
+		{
+			this.project = project;
+		}
+
 		/// <summary>
 		/// Runs the `dotnet` tool with the specified arguments.
 		/// </summary>
@@ -73,6 +78,16 @@ protected bool Execute (params string [] args)
 			return succeeded;
 		}
 
+		public bool New (string template, string output = null)
+		{
+			var arguments = new List<string> {
+				"new",
+				template,
+				"--output", $"\"{output ?? ProjectDirectory}\"",
+			};
+			return Execute (arguments.ToArray ());
+		}
+
 		public bool Build (string target = null, string [] parameters = null)
 		{
 			var arguments = GetDefaultCommandLineArgs ("build", target, parameters);
@@ -123,14 +138,16 @@ List<string> GetDefaultCommandLineArgs (string verb, string target = null, strin
 			var arguments = new List<string> {
 				verb,
 				$"\"{projectOrSolution}\"",
-				$"/p:Configuration={project.Configuration}",
 				"/noconsolelogger",
 				$"/flp1:LogFile=\"{BuildLogFile}\";Encoding=UTF-8;Verbosity={Verbosity}",
 				$"/bl:\"{Path.Combine (testDir, "msbuild.binlog")}\""
 			};
 			if (!string.IsNullOrEmpty (target)) {
 				arguments.Add ($"/t:{target}");
 			}
+			if (project != null) {
+				arguments.Add ($"/p:Configuration={project.Configuration}");
+			}
 			if (Directory.Exists (AndroidSdkPath)) {
 				arguments.Add ($"/p:AndroidSdkDirectory=\"{AndroidSdkPath}\"");
 			}

src/templates/Directory.Build.targets

@@ -0,0 +1,15 @@
+<Project>
+  <Import Project="..\..\build-tools\scripts\XAVersionInfo.targets" />
+  <PropertyGroup>
+    <BeforePack>
+      _GetDefaultPackageVersion;
+      $(BeforePack);
+    </BeforePack>
+  </PropertyGroup>
+  <Target Name="_GetDefaultPackageVersion"
+      DependsOnTargets="GetXAVersionInfo" >
+    <PropertyGroup>
+      <PackageVersion>$(AndroidPackVersionLong)+sha.$(XAVersionHash)</PackageVersion>
+    </PropertyGroup>
+  </Target>
+</Project>

src/templates/android-activity/.template.config/template.json

@@ -0,0 +1,25 @@
+{
+  "$schema": "http://json.schemastore.org/template",
+  "author": "Microsoft",
+  "classifications": [ "Android" ],
+  "name": "Android Activity template",
+  "description": "An Android Activity class",
+  "tags": {
+    "language": "C#",
+    "type": "item"
+  },
+  "identity": "Microsoft.Android.AndroidActivity",
+  "shortName": "android-activity",
+  "sourceName": "Activity1",
+  "primaryOutputs": [
+    { "path": "Activity1.cs" }
+  ],
+  "defaultName": "Activity1",
+  "symbols": {
+    "namespace": {
+      "description": "namespace for the generated code",
+      "replaces": "AndroidApp1",
+      "type": "parameter"
+    }
+  }
+}