单元测试的Windows 8 Store应用UI（XAML控件）(Unit Testing Wind

我已经创建一个Windows Store应用，但我有螺纹的问题测试它创建了一个网格（这是一个XAML控制）的方法。我试着使用NUnit和MSTest的测试。

该测试方法是：

[TestMethod]
public void CreateThumbnail_EmptyLayout_ReturnsEmptyGrid()
{
    Layout l = new Layout();
    ThumbnailCreator creator = new ThumbnailCreator();
    Grid grid = creator.CreateThumbnail(l, 192, 120);

    int count = grid.Children.Count;
    Assert.AreEqual(count, 0);
}

和creator.CreateThumbnail（这引发错误的方法）：

public Grid CreateThumbnail(Layout l, double totalWidth, double totalHeight)
{
     Grid newGrid = new Grid();
     newGrid.Width = totalWidth;
     newGrid.Height = totalHeight;

     SolidColorBrush backGroundBrush = new SolidColorBrush(BackgroundColor);
     newGrid.Background = backGroundBrush;

     newGrid.Tag = l;            
     return newGrid;
}

当我运行这个测试，它抛出这个错误：

System.Exception: The application called an interface that was marshalled for a different thread. (Exception from HRESULT: 0x8001010E (RPC_E_WRONG_THREAD))

您的控件相关的代码必须在UI线程中运行。尝试：

[TestMethod]
async public Task CreateThumbnail_EmptyLayout_ReturnsEmptyGrid()
{
    int count = 0;
    await ExecuteOnUIThread(() =>
    {
        Layout l = new Layout();
        ThumbnailCreator creator = new ThumbnailCreator();
        Grid grid = creator.CreateThumbnail(l, 192, 120);
        count = grid.Children.Count;
    });

    Assert.AreEqual(count, 0);
}

public static IAsyncAction ExecuteOnUIThread(Windows.UI.Core.DispatchedHandler action)
{
    return Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, action);
}

上述应MS测试工作。我不知道NUnit的。