DesignInstance在VS2013中不起作用

Question

Visual Studio不显示具有DesignInstance属性的设计时数据.我已经检查DesignInstance过/没有MVVM Light.我花了很多时间来解决这个问题(也检查了StackOverflow上的类似问题),但DesignInstance根本不起作用.

项目:

• SearchIdView.
• SearchIdViewModel - 真实的视图模型.
• DesignSearchIdViewModel- 继承SearchIdViewModel并包含设计时数据(属性在构造函数中分配).

环境:

• VS2013 SP3
• 净4.0
• MvvmLight 5.0.2.0

SearchIdView.xaml

<Window x:Class="App1.View.SearchIdView"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:ignore="http://www.ignore.com"
    xmlns:design="clr-namespace:App1.Design"
    mc:Ignorable="d ignore"
    DataContext="{Binding SearchId, Source={StaticResource Locator}}"
    d:DataContext="{d:DesignInstance d:Type=design:DesignSearchIdViewModel,IsDesignTimeCreatable=True}"
    >
<Grid>
    <TextBlock Text="{Binding Test}" />
</Grid>

SearchIdViewModel.cs

物业来自 SearchIdViewModel

public const string TestPropertyName = "Test";
private string _test;
public string Test
{
  get
  {
    return _test;
  }
  set
  {
    Set(TestPropertyName, ref _test, value);
  }
}

你知道为什么DesignInstance在这种情况下不起作用吗？

解决方法

• d:DataContext从视图中删除
• 添加界面ISearchIdViewModel(它是空的)
• SearchIdViewModel 继承自 ISearchIdViewModel
• 改变ViewModelLocator(下面)

ViewModelLocator.cs

public class ViewModelLocator
{
  static ViewModelLocator()
  {
    ServiceLocator.SetLocatorProvider(() => SimpleIoc.Default);
    if (ViewModelBase.IsInDesignModeStatic)
    {
      SimpleIoc.Default.Register<ISearchIdViewModel,Design.DesignSearchIdViewModel>();
    }
    else
    {
    SimpleIoc.Default.Register<ISearchIdViewModel, SearchIdViewModel>();
    }
  }

  public SearchIdViewModel SearchId
  {
    get { return (SearchIdViewModel) ServiceLocator.Current.GetInstance<ISearchIdViewModel>(); }
  }
}

Answer 1

你的d:DesignInstance声明格式不正确.您指定属性名称d:Type而不是Type,因此未正确分配属性.替换d:Type为Type,或者完全保留属性名称,并将其推断为默认属性.

d:DataContext="{d:DesignInstance d:Type=design:DesignSearchIdViewModel,
                                 IsDesignTimeCreatable=True}"

应该成为:

d:DataContext="{d:DesignInstance Type=design:DesignSearchIdViewModel,
                                 IsDesignTimeCreatable=True}"

或者,或者:

d:DataContext="{d:DesignInstance design:DesignSearchIdViewModel,
                                 IsDesignTimeCreatable=True}"

_{(为了便于阅读,添加了换行)}