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我们先从FrontUWP工程讲起，AppServiceHandler.cs是我创建的帮助Class，用来处理AppServiceConnectoin的Connected和RequestReceived事件。 复制代码 public void OnBackgroundActivated(AppServiceTriggerDetails details) { Connected?.Invoke(this, new AppServiceConnectionConnectedEventArgs(details.AppServiceConnection)); Connection = details.AppServiceConnection; Connection.RequestReceived += Connection_RequestReceived; } private void Connection_RequestReceived(AppServiceConnection sender, AppServiceRequestReceivedEventArgs args) { RequestReceived?.Invoke(this, args); }复制代码 而OnBackgroundActivated事件则是在App.xaml.cs中，通过override UWP Application对象的OnBackgroundActivated方法来触发。这里是AppServiceConnection连接的起点，即源头。 复制代码 protected override void OnBackgroundActivated(BackgroundActivatedEventArgs args) { base.OnBackgroundActivated(args); if (args.TaskInstance.TriggerDetails is AppServiceTriggerDetails details) { if (details.CallerPackageFamilyName == Package.Current.Id.FamilyName) { var deferral = args.TaskInstance.GetDeferral(); args.TaskInstance.Canceled += (sender, e) => { deferral?.Complete(); }; AppServiceHandler.Instance.OnBackgroundActivated(details); } } } 复制代码 以上这些在前面几篇中都有提及，这里不再赘述。在UWP工程的MainPage中，我们记录了UWP进程的process id，Desktop Extension段会读取该值，用以检测UWP process的Exit事件，在UWP被关闭时释放资源。同时通过RequestReceived事件来将Desktop Extension反向通知的HotKey的值，通过HotKeyList绑定显示到UWP的界面上。 复制代码 protected async override void OnNavigatedTo(NavigationEventArgs e) { base.OnNavigatedTo(e); Process process = Process.GetCurrentProcess(); ApplicationData.Current.LocalSettings.Values[“processId”] = process.Id; if (ApiInformation.IsApiContractPresent(“Windows.ApplicationModel.FullTrustAppContract”, 1, 0)) { await FullTrustProcessLauncher.LaunchFullTrustProcessForCurrentAppAsync(); } AppServiceHandler.Instance.RequestReceived += Instance_RequestReceived; } private async void Instance_RequestReceived(object sender, Windows.ApplicationModel.AppService.AppServiceRequestReceivedEventArgs e) { var message = e.Request.Message; if (message.TryGetValue("HotKey", out object keyCode)) { await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.High, () => { HotKeyList.Add(keyCode.ToString()); }); } }复制代码 最后不要忘记给FrontUWP工程添加对Windows Desktop Extension for the UWP的引用。 我们转到Desktop这一边，ReverseNotificatio.Desktop是一个WinForms的程序，通过RegisterHotKey这个Win32的API来监听热键。如何实现监听热键我不做过多介绍，具体请参考示例代码。 [DllImport("user32.dll")] public static extern bool RegisterHotKey(IntPtr hWnd, int id, int fsModifiers, int vlc);同时为了使用AppServiceConnection，添加了对Win10 API的引用，主要是WindowsRuntime和Windows.winmd这两个文件。前者通过Nuget添加，后者请参考《迁移桌面程序到MS Store（4）——桌面程序调用Win10 API》。 我想强调的是，不要在长生命周期的Desktop Extension进程中，去维护一个全局的AppServiceConnection，某软的文档并没有提到细节，但也明确指出AppServiceConnection在UWP进入suspended状态时，可能被释放。我们要做的事情，是在每一次的热键响应事件中，创建新的AppServiceConnection去发送消息。 复制代码 private async void hotkeys_HotkeyPressed(int ID) { var key = Enum.GetName(typeof(VirtualKey), ID); var message = new ValueSet { { "HotKey", key } }; var connection = new AppServiceConnection { PackageFamilyName = Package.Current.Id.FamilyName, AppServiceName = "ReverseNotificationAppService" }; connection.ServiceClosed += Connection_ServiceClosed; var status = await connection.OpenAsync(); if (status == AppServiceConnectionStatus.Success) { var response = await connection.SendMessageAsync(message); } }复制代码 不能保存已创建的AppServiceConnection来重复使用，有时会造成不便。但这也正是我将Desktop Extension分为4个场景的原因，针对不同的用途来创建特定类型的background process。 ReverseNotification.Package作为打包工程，我们需要注意添加对FrontUWP和Desktop的引用。以及编辑Package.appxmanifest文件，提供对AppService和Desktop Extension的支持。 复制代码 USB Microphone https://www.soft-voice.com/ Wooden Speakers https://www.zeshuiplatform.com/ 亚马逊测评 www.yisuping.cn 深圳网站建设www.sz886.com |
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