Catel with Xamarin.Forms

Question

我无法获得Xamarin.Forms和Catel一起工作。

我看到这个sample但它似乎已过时。

当我通过的NuGet下载Catel，我得到不同的问题，不同的版本：

• V5.1：

  编译时异常：

  Exception while loading assemblies: System.IO.FileNotFoundException: Could not load assembly 'Obsolete, Version=4.2.4.0, Culture=neutral, PublicKeyToken=1ca091877d12ca03'. Perhaps it doesn't exist in the Mono for Android profile?

• v5.0：

  运行时例外（创建时new App();）：

  Could not load signature of Catel.MVVM.IViewModelFactory:CreateViewModel due to: Could not resolve type with token 01000061 (from typeref, class/assembly System.ComponentModel.IDataErrorInfo, Catel.Core, Version=5.0.0.0, Culture=neutral, PublicKeyToken=null) assembly:Catel.Core, Version=5.0.0.0, Culture=neutral, PublicKeyToken=null type:System.ComponentModel.IDataErrorInfo member:<none>

• V4.5 *

  • 使用ViewModelBase：创建应用程序对象时

    运行时异常： 系统。 TypeLoadException：无法与解析式令牌 01000097（从typeref，类/装配System.Reflection.BindingFlags，Catel.Core，版本= 4.5.4.0，文化=中性公钥= NULL）

  • 我实施IViewModel：

    好吧，主页加载，绑定工作，构造函数通过参数获取正确的服务，但是，例如，当我调用'_uiVisualizerService.Show（subPageViewModel）;'从命令中，它会抛出'InvalidCastException'。 Catel日志中的最后一行例外：Injecting properties into type 'SubPage' after construction。但是SubPage和SubPageViewModel绝对是空的。

    详情：

    ---> System.InvalidCastException: Specified cast is not valid. at Catel.Services.UIVisualizerService+<ShowAsync>d__9.MoveNext() [0x00096] in C:\CI_WS\Ws\97969\Source\Catel\src\Catel.MVVM\Catel.MVVM.Xamarin.Forms\Services\UIVisualizerService.cs:151 at System.Threading.Tasks.Task.ThrowIfExceptional (System.Boolean includeTaskCanceledExceptions) [0x00011] in <183b200ee49746d48fc781625979428e>:0 at System.Threading.Tasks.Task'1[TResult].GetResultCore (System.Boolean waitCompletionNotification) [0x0002b] in <183b200ee49746d48fc781625979428e>:0 at System.Threading.Tasks.Task'1[TResult].get_Result() [0x0000f] in <183b200ee49746d48fc781625979428e>:0 at Catel.Services.UIVisualizerService.Show (Catel.MVVM.IViewModel viewModel, System.EventHandler``1[TEventArgs] completedProc) [0x00000] in C:\CI_WS\Ws\97969\Source\Catel\src\Catel.MVVM\Catel.MVVM.Xamarin.Forms\Services\UIVisualizerService.cs:125 at XamarinFormsCatel.ViewModels.MainPageViewModel.OnGo() [0x00015] in C:\!Work\Test\XamarinFormsCatel\XamarinFormsCatel\XamarinFormsCatel\XamarinFormsCatel\ViewModels\MainPageViewModel.cs:34 at Xamarin.Forms.Command+<>c__DisplayClass3_0.<.ctor>b__0 (System.Object o) [0x00000] in C:\BuildAgent3\work\ca3766cfc22354a1\Xamarin.Forms.Core\Command.cs:73 at Xamarin.Forms.Command.Execute (System.Object parameter) [0x00000] in C:\BuildAgent3\work\ca3766cfc22354a1\Xamarin.Forms.Core\Command.cs:107 at Xamarin.Forms.Button.Xamarin.Forms.IButtonController.SendClicked() [0x0000a] in C:\BuildAgent3\work\ca3766cfc22354a1\Xamarin.Forms.Core\Button.cs:121 at Xamarin.Forms.Platform.Android.AppCompat.ButtonRenderer+ButtonClickListener.OnClick (Android.Views.View v) [0x0000b] in C:\BuildAgent3\work\ca3766cfc22354a1\Xamarin.Forms.Platform.Android\AppCompat\ButtonRenderer.cs:298 at Android.Views.View+IOnClickListenerInvoker.n_OnClick_Landroid_view_View_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_v) [0x0000f] in <71828dd8fb5f4508815e23d6996c45c2>:0 at (wrapper dynamic-method) System.Object:4c9f6786-8ab0-4bd8-bdb1-4cc7a3d7ddc7 (intptr,intptr,intptr) -> (Inner Exception #0) System.InvalidCastException: Specified cast is not valid. at Catel.Services.UIVisualizerService+<ShowAsync>d__9.MoveNext() [0x00096] in C:\CI_WS\Ws\97969\Source\Catel\src\Catel.MVVM\Catel.MVVM.Xamarin.Forms\Services\UIVisualizerService.cs:151 <---

我该怎么办：

• 变化defalt Catel.MVVM.dll参考android项目从MonoAndroid到portable-net45+wp8+win8+wpa81+MonoAndroid10+MonoTouch10+Xamarin.iOS10+UAP10。如果没有完成，编译将失败。

• MainPage.xaml中

  <catel:ContentPage ... xmlns:catel="clr-namespace:Catel.Windows.Controls;assembly=Catel.MVVM">

• MainPageViewModel。CS

  public class MainPageViewModel : ViewModelBase { }

• App.cs

  public class App : Catel.Xamarin.Forms.Application<Views.MainPage> { }

• MainActivity.cs（机器人）

  public class MainActivity : Xamarin.Forms.Platform.Android.FormsAppCompatActivity 
  { 
      protected override void OnCreate(Bundle bundle) 
      { 
       TabLayoutResource = Resource.Layout.Tabbar; 
       ToolbarResource = Resource.Layout.Toolbar; 
  
       base.OnCreate(bundle); 
  
       Xamarin.Forms.Forms.Init(this, bundle); 
  
       var app = new App(); 
       LoadApplication(app); 
      } 
  } 
  

Windows 7中，64倍。 Xamarin.Forms：2.3.4.267

任何帮助非常感激。

Answer 1

该团队正在改进对Xamarin.Forms的支持。目前没有例子。预计将在未来几个月内完成对Xamarin.Forms的v5支持。