WPF MVVM +如何让两个控件绑定到不同的属性？

我有一个使用MVVM模式的WPF应用程序。WPF MVVM +如何让两个控件绑定到不同的属性？

在用户控件上，我有两个DataGrid的ItemsSource绑定到两个不同的属性。

其中一个DataGrid的填充正确，但另一个不是。我想不出有什么不好的绑定。我试图明确地设置DataGrid的DataContext不工作，但我不知道为什么我应该这样做，或者在哪里做。

我已验证数据的检索正在工作，因为我可以调试并查看数据，并且DataGrid具有'可点击'的行，但没有文本显示。

AssignItemsToCategoryViewModel.cs

/// <summary> 
    /// Describes the name that will be used for the menu option 
    /// Implemented from IPageViewModel 
    /// </summary> 
    public string Name 
    { 
     get { return "Assign Items To Categories "; } 

    } 

    #region Categories 
    private CategoryModel _currentCategory; 
    public CategoryModel CurrentCategory 
    { 
     get { return _currentCategory; } 
     set 
     { 
      _currentCategory = value;    
      OnPropertyChanged("CurrentCategory"); 
     }  
    } 

    public ObservableCollection<CategoryModel> Categories = new ObservableCollection<CategoryModel>(); 

    public RelayCommand GetCategoriesRelay; 

    public AssignItemsToCategoryViewModel() 
    { 
     CurrentCategory = new CategoryModel(); 
     CurrentStockItem = new StockItemModel(); 
    } 

    #region Get Categories Command 
    /// <summary> 
    /// The interface command 
    /// to run the get GetCategories method 
    /// </summary> 
    public ICommand GetCategoriesCommand 
    { 
     get 
     { 
      GetCategoriesRelay = new RelayCommand(p => GetCategories(), 
       p => CanGetCategories()); 

      return GetCategoriesRelay; 
     } 
    } 

    /// <summary> 
    /// Checks whether the GetCategories command can be run 
    /// </summary> 
    /// <returns>True or False</returns> 
    private bool CanGetCategories() 
    { 
     return true; 
    } 

    /// <summary> 
    /// Method to fetch the categories 
    /// </summary> 
    private void GetCategories() 
    { 
     Categories = CurrentCategory.GetCategories(); 
     ReceivedCategories = Categories; 

     if (Categories.Any()) 
      SelectedIndex = 0; 

    } 

    #endregion 


    /// <summary> 
    /// Gets or sets the DataGrid's selected index 
    /// Used to set the index to 0 if any categories exist. 
    /// </summary> 
    private int _selectedIndex; 
    public int SelectedIndex 
    { 
     get { return _selectedIndex; } 
     set 
     { 
      _selectedIndex = value; 
      OnPropertyChanged("SelectedIndex"); 
     } 
    } 



    /// <summary> 
    /// Gets or sets the collection of received categories 
    /// </summary> 
    public ObservableCollection<CategoryModel> ReceivedCategories 
    { 
     get { return Categories; } 

     set 
     { 
      Categories = value; 
      OnPropertyChanged("ReceivedCategories"); 
     } 
    } 
    #endregion 

    #region Stock Items 

    private StockItemModel _currentStockItem; 
    public StockItemModel CurrentStockItem 
    { 
     get { return _currentStockItem; } 
     set 
     { 
      _currentStockItem = value; 
      OnPropertyChanged("CurrentStockItem"); 
     } 
    } 

    public ObservableCollection<StockItemModel> StockItems = new ObservableCollection<StockItemModel>(); 

    public RelayCommand GetStockItemsRelay; 
    public RelayCommand LinkItemRelay; 
    public RelayCommand UnlinkItemRelay; 


    #region Get Stock Items Command 

    /// <summary> 
    /// The interface command 
    /// to run the get GetStockItems method 
    /// </summary> 
    public ICommand GetStockItemsCommand 
    { 
     get 
     { 
      GetStockItemsRelay = new RelayCommand(p => GetStockItems(), 
       p => CanGetStockItems()); 

      return GetStockItemsRelay; 
     } 
    } 

    /// <summary> 
    /// Checks whether the GetStockItems command can be run 
    /// </summary> 
    /// <returns>True or False</returns> 
    private bool CanGetStockItems() 
    { 
     return true; 
    } 

    /// <summary> 
    /// Method to fetch the stock items 
    /// </summary> 
    private void GetStockItems() 
    { 
     StockItems = CurrentStockItem.GetStockItems(); 
     ReceivedStockItems = StockItems; 

     if (ReceivedStockItems.Any()) 
      SelectedStockItemIndex = 0; 

    } 

    #endregion 

    /// <summary> 
    /// Gets or sets the Stock Items DataGrid's selected index 
    /// Used to set the index to 0 if any stock items exist. 
    /// </summary> 
    private int _selectedStockItemIndex; 
    public int SelectedStockItemIndex 
    { 
     get { return _selectedStockItemIndex; } 
     set 
     { 
      _selectedStockItemIndex = value; 
      OnPropertyChanged("SelectedStockItemIndex"); 
     } 
    } 

    /// <summary> 
    /// Gets or sets the CurerntStockItem Id 
    /// </summary> 
    public long? StockLinkId 
    { 
     get { return CurrentStockItem.StockLink; } 
     set 
     { 
      CurrentStockItem.StockLink = value; 
      OnPropertyChanged("StockLinkId"); 
     } 
    } 

    /// <summary> 
    /// Gets or sets the CurrentStockItem ItemCode 
    /// </summary> 
    public string ItemCode 
    { 
     get 
     { 
      return CurrentStockItem.ItemCode; 
     } 
     set 
     { 
      CurrentStockItem.ItemCode = value; 

      OnPropertyChanged("ItemCode"); 
     } 
    } 

    /// <summary> 
    /// Gets or sets the collection of received categories 
    /// </summary> 
    public ObservableCollection<StockItemModel> ReceivedStockItems 
    { 
     get { return StockItems; } 

     set 
     { 
      StockItems = value; 
      OnPropertyChanged("ReceivedStockItems"); 
     } 
    } 

    #endregion 
}

AssignItemsToCategoryView.xaml

<UserControl x:Class="SalesLinker.View.AssignItemsToCategoryView" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"  
    mc:Ignorable="d" 
    d:DesignHeight="300" d:DesignWidth="600" Background="White"> 

<i:Interaction.Triggers> 
    <i:EventTrigger EventName="Loaded"> 
     <i:InvokeCommandAction Command="{Binding GetCategoriesCommand}" /> 
     <i:InvokeCommandAction Command="{Binding GetStockItemsCommand}" /> 
    </i:EventTrigger> 
</i:Interaction.Triggers> 

<Grid> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="45"/> 
     <RowDefinition Height="*"/> 
    </Grid.RowDefinitions> 
    <Grid.ColumnDefinitions> 
     <ColumnDefinition Width="250"/> 
     <ColumnDefinition Width="100"/> 
     <ColumnDefinition Width="*"/> 
    </Grid.ColumnDefinitions> 


    <Border Grid.Column="0" Grid.Row="0" Grid.RowSpan="2" VerticalAlignment="Stretch" 
      Style="{StaticResource MainBorderStyle}" > 

     <HeaderedContentControl x:Name="ItemsList" 
           Style="{StaticResource MainHCCStyle}" 
           Header="Items"> 

      <DataGrid x:Name="LstItems" Grid.Column="0" Grid.Row="1" AutoGenerateColumns="false" IsReadOnly="True" 
       ItemsSource="{Binding Path=ReceivedStockItems, Mode=TwoWay}" 
       HorizontalScrollBarVisibility="Disabled" GridLinesVisibility="None" 
       CanUserAddRows="False" CanUserDeleteRows="False" CanUserSortColumns="True" Background="White" 
       SelectedIndex="{Binding Path=SelectedStockItemIndex}" > 
       <DataGrid.Columns> 
        <DataGridTextColumn Binding="{Binding Path=ItemCode}" IsReadOnly="True" Header="Item Code" Width="300" /> 
       </DataGrid.Columns> 
      </DataGrid> 
     </HeaderedContentControl> 
    </Border> 

    <DockPanel Grid.Row="1" Grid.Column="1"> 
     <StackPanel VerticalAlignment="Center" > 

      <StackPanel.Resources> 
       <Style TargetType="{x:Type Button}"> 
        <Setter Property="Margin" Value="0,10,0,0"/> 
       </Style> 
      </StackPanel.Resources> 
       <Button Command="{Binding LinkItemCommand}" Height="50" Width="50" Background="Transparent" BorderThickness="0" BorderBrush="Transparent" 
        CommandParameter="{Binding ElementName=TbDescription, Path=Text}"> 
       <Image Source="/Images/RightArrow.png"/> 
      </Button> 

      <Button Command="{Binding UnlinkItemCommand}" Height="50" Width="50" Background="Transparent" BorderThickness="0" BorderBrush="Transparent" 
         CommandParameter="{Binding SelectedItem.CategoryID, ElementName=LstCategories, Mode=OneWay }" > 
       <Image Source="/Images/LeftArrow.png"/> 
      </Button> 

     </StackPanel> 
    </DockPanel> 


    <Border Grid.Column="2" Grid.Row="0" Grid.RowSpan="2" VerticalAlignment="Stretch" 
      Style="{StaticResource MainBorderStyle}" > 

     <HeaderedContentControl x:Name="CategoryItems" 
           Style="{StaticResource MainHCCStyle}" 
           Header="Categories"> 

      <DataGrid x:Name="LstCategories" Grid.Column="0" Grid.Row="1" AutoGenerateColumns="false" IsReadOnly="True" 
       ItemsSource="{Binding Path=ReceivedCategories, Mode=TwoWay}" 
       HorizontalScrollBarVisibility="Disabled" GridLinesVisibility="None" 
       CanUserAddRows="False" CanUserDeleteRows="False" CanUserSortColumns="True" Background="White" 
       SelectedIndex="{Binding Path=SelectedIndex}"> 


       <DataGrid.Columns> 
        <DataGridTextColumn Binding="{Binding Path=Description}" IsReadOnly="True" Header="Description" Width="300" /> 
       </DataGrid.Columns> 
      </DataGrid> 
     </HeaderedContentControl> 
    </Border> 

</Grid>

数据网格命名LstCategories正常工作，但LstItems的问题。

来源

2016-04-20 Neill

有没有在你的问题太多东西我梳理一下，看看问题出在哪里。今后，请帮助我们通过创建演示您的问题的最低版本的代码来帮助您。 70％的时间只是这样做会回答你的问题，因为你发现你的错误（protip：它隐藏在所有其他代码的草垛中）。另外，输出窗口应该有绑定错误。检查他们？如果不是，请搜索调试绑定错误。最后，获取Snoop并在运行时检查绑定。这有时也有帮助。 – Will

谢谢Will，snoop帮我找到了我这么愚蠢的错误。 – Neill

太好了。我扫描了你的代码，并且会看到一些很明显的东西，但是我的时间太多了。问问题时，将代码放在一起非常重要。 – Will

所以这个问题真的很愚蠢。我猜如果我展示了我的模特班，大多数人会立即发现它。

我忘了getter和setter添加到我的财产在我的模型类

所以我不得不

public string ItemCode;

代替：

public string ItemCode {get; set;}

来源

2016-04-21 08:52:21 Neill

WPF MVVM +如何让两个控件绑定到不同的属性？

回答

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