UWP / MVVMlight：替换过时的 ServiceLocator

Question

我正在更新我的应用程序，现在我使用 MVVMLight 5.3.0 viewmodellocator 崩溃了

ServiceLocator.SetLocatorProvider(() => SimpleIoc.Default);

我读到最新版本的 MVVMLight，类 servicelocartor 被删除，Microsoft.Practices.ServiceLocation 消失了......

那么，我可以/必须做什么才能让应用再次运行？ 谢谢

Answer 1

从介绍MVVMLight标准库版本的博文中，去掉下面这行代码：

// OLD ServiceLocator.SetLocatorProvider(() => SimpleIoc.Default);

每当您使用 ServiceLocator.Current 时，请改用 SimpleIoc.Default。例如

// OLD var nav = ServiceLocator.Current.GetInstance<INavigationService>();
// NEW
var nav = SimpleIoc.Default.GetInstance<INavigationService>();

http://www.mvvmlight.net/std10

Answer 2

我总是以这种方式使用 MVVMLight，而不为 ServiceLocator 设置定位器提供程序。通常，您的视图模型定位器应如下所示：

public class ViewModelLocator
{
    public ViewModelLocator()
    {
        SimpleIoc.Default.Register<IDataProvider, SQLiteDataProvider>();
        SimpleIoc.Default.Register<IDialogService, DialogService>();
        SimpleIoc.Default.Register(GetNavigationService);
        SimpleIoc.Default.Register<MainViewModel>();
        SimpleIoc.Default.Register<MessageViewModel>();
        SimpleIoc.Default.Register<SearchViewModel>();
        SimpleIoc.Default.Register<SettingViewModel>();
        ...
    }

    public MainViewModel MainViewModel => SimpleIoc.Default.GetInstance<MainViewModel>(Guid.NewGuid().ToString());
    public MessageViewModel MessageViewModel => SimpleIoc.Default.GetInstance<MessageViewModel>(Guid.NewGuid().ToString());
    public SearchViewModel SearchViewModel => SimpleIoc.Default.GetInstance<SearchViewModel>(Guid.NewGuid().ToString());
    public SettingViewModel SettingViewModel => SimpleIoc.Default.GetInstance<SettingViewModel>(Guid.NewGuid().ToString());
    ...

    public INavigationService GetNavigationService()
    {
        var navigationService = new NavigationService();
        navigationService.Configure(Pages.MainView.ToString(), typeof(MainPage));
        navigationService.Configure(Pages.MessageView.ToString(), typeof(MessagePage));
        navigationService.Configure(Pages.SearchView.ToString(), typeof(SearchPage));
        navigationService.Configure(Pages.SettingView.ToString(), typeof(SettingPage));
        ...
        return navigationService;
    }
}