[UWP] 背景處理Cortana 的Voice Command 請求

前言

如果你希望開發一支UWP在背景處理事情, 然後將處理完的資料或狀態顯示在Cortana的Canvas上面的話, 我們會需要寫一個backgound server去處理Cortana的請求, 而基本上有以下幾個步驟

Step 1. 前置步驟

新增專案

選擇Windows Runtime Component

專案建立好之後, 我們先把Class1.cs重新命名(列如 MyVoiceCommandService.cs)

設定Package.appxmanifest

加入以下的程式碼, 然後把EntryPoint指定到剛剛建立的MyVoiceCommandService.cs

	<Extensions>
	<uap:Extension Category="windows.appService"
	EntryPoint="VCDService.MyVoiceCommandService">
	<uap:AppService Name="MyVoiceCommandService"/>
	</uap:Extension>
	<uap:Extension Category="windows.personalAssistantLaunch"/>
	</Extensions>

view raw Package.appxmanifest.xml hosted with ❤ by GitHub

編輯VoiceCommand.xml

	<Command Name="findMovie">
	<Example> Find a movie</Example>
	<ListenFor RequireAppName="BeforeOrAfterPhrase"> find {MovieName} </ListenFor>
	<ListenFor RequireAppName="ExplicitlySpecified"> find {MovieName} from {builtin:AppName} </ListenFor>
	<ListenFor RequireAppName="ExplicitlySpecified"> {builtin:AppName} add {MovieName}</ListenFor>
	<Feedback> Finding ... </Feedback>
	<VoiceCommandService Target="MyVoiceCommandService" />
	</Command>

view raw MyVoiceCommand.xml hosted with ❤ by GitHub

實作IBackgroundTask

	using System;
	using System.Collections.Generic;
	using System.Linq;
	using System.Text;
	using System.Threading.Tasks;
	using Windows.ApplicationModel.Background;
	using Windows.ApplicationModel.VoiceCommands;
	using Windows.ApplicationModel.Resources.Core;
	using Windows.ApplicationModel.AppService;
	using Windows.Storage;
	namespace VCDService
	{
	public sealed class MyVoiceCommandService:IBackgroundTask
	{
	private BackgroundTaskDeferral serviceDefferral;
	VoiceCommandServiceConnection voiceCommandServiceConnection;
	public async void Run(IBackgroundTaskInstance taskInstance)
	{
	this.serviceDefferral = taskInstance.GetDeferral();
	taskInstance.Canceled += OnTaskCanceled;
	var triggerDetails = taskInstance.TriggerDetails as AppServiceTriggerDetails;
	if(triggerDetails!=null && triggerDetails.Name == "MyVoiceCommandService")
	{
	// Something to do
	// We have to handle voice command request here
	}
	}
	private void OnVoiceCommandCompleted(VoiceCommandServiceConnection sender, VoiceCommandCompletedEventArgs args)
	{
	if (this.serviceDefferral != null)
	{
	this.serviceDefferral.Complete();
	}
	}
	private void OnTaskCanceled(IBackgroundTaskInstance sender, BackgroundTaskCancellationReason reason)
	{
	System.Diagnostics.Debug.WriteLine("Task canceled");
	if(this.serviceDefferral!= null)
	{
	this.serviceDefferral.Complete();
	}
	}
	}
	}

view raw MyVoiceCommandService.cs hosted with ❤ by GitHub

Step 2. 處理Cortana VoiceCommand的請求

取得VoiceCommandServiceConnection實體

這是用來讓我們的背景程式與Cortana溝通的介面

	voiceCommandServiceConnection =
	VoiceCommandServiceConnection.FromAppServiceTriggerDetails(triggerDetails);

view raw MyVoiceCommandService.cs hosted with ❤ by GitHub

建立Response的內容

基本上我們可以回傳VoiceCommandUserMessage, VoiceCommandContentTile這兩種內容給Cortana

User Messag
讓Cortana說話, 或是讓她秀訊息在Canvas上面

	//Message
	VoiceCommandUserMessage userMessage = new VoiceCommandUserMessage()
	{
	DisplayMessage = "Here you are",
	SpokenMessage = "Here you are"
	};

view raw MyVoiceCommandService.cs hosted with ❤ by GitHub

Content Tile
這個有點像是Bot Framework中的Card, 我們可以把文字跟圖片塞在Content Tile中讓Canvas顯示出來, 我們可以一次回傳多個Content Tile, 當使用者點了其中一個之後, 就會觸發開啟我們程式的事件

	//Tile
	VoiceCommandContentTile contentTile = new VoiceCommandContentTile()
	{
	ContentTileType = VoiceCommandContentTileType.TitleWith280x140Icon,
	Title = moviceName,
	Image = await StorageFile.GetFileFromApplicationUriAsync(new Uri(@"ms-appx:///Images/IMDB_Logo.png"))
	};

view raw MyVoiceCommandService.cs hosted with ❤ by GitHub

VoiceCommandResponse

建立VoiceCommandResponse的實體, 然後塞入剛剛建立的VoiceCommandUserMessage 或是 VoiceCommandContentTile, 最後再透過VoiceCommandServiceConnection回傳給Cortana

	VoiceCommandResponse response =
	VoiceCommandResponse.CreateResponse(
	userMessage, new List<VoiceCommandContentTile>() { contentTile }
	);
	await voiceCommandServiceConnection.ReportSuccessAsync(response);

view raw MyVoiceCommandService.cs hosted with ❤ by GitHub

Demo

Hey Cortana, find God Father on My Library

完整程式碼

https://github.com/andy51002000/Simple-UWP-With-VoiceCommand.git