樹視圖綁定wpf無法綁定類中的嵌套屬性

Question

wpf新手，因此掙扎了一下。 我是一個快速演示放在一起，我們去爲全面實施 之前，我對剩下的

Continent 
    Country 
     City structure 

當用戶選擇城市應該填充一些文本框在一個TabControl右手邊一個TreeView

我做了一些工作，但不能使它與複合對象一起工作。

簡而言之，你可以發現我的zaml或代碼有什麼問題。 爲什麼不綁定到我的CityDetails.ClubsCount或CityDetails.PubsCount？

什麼，我是基於http://www.codeproject.com/KB/WPF/TreeViewWithViewModel.aspx

由於建設很多關於任何建議或回覆

的DataModel

public class City 
{ 
    public City(string cityName) 
    { 
     CityName = cityName; 
    } 

    public string CityName { get; set; } 
    public string Population { get; set; } 
    public string Area { get; set; } 
    public CityDetails CityDetailsInfo { get; set; } 
} 

public class CityDetails 
{ 
    public CityDetails(int pubsCount,int clubsCount) 
    { 
     PubsCount = pubsCount; 
     ClubsCount = clubsCount; 
    } 

    public int ClubsCount { get; set; } 
    public int PubsCount { get; set; } 
} 

視圖模型

public class CityViewModel : TreeViewItemViewModel 
{ 
    private City _city; 
    private RelayCommand _testCommand; 
    public CityViewModel(City city, CountryViewModel countryViewModel):base(countryViewModel,false) 
    { 
     _city = city; 
    } 

    public string CityName 
    { 
     get { return _city.CityName; } 
    } 
    public string Area 
    { 
     get { return _city.Area; } 
    } 
    public string Population 
    { 
     get { return _city.Population; } 
    } 
    public City City 
    { 
    get { return _city; } 
    set { _city = value; } 
    } 

    public CityDetails CityDetailsInfo 
    { 
     get { return _city.CityDetailsInfo; } 
     set { _city.CityDetailsInfo = value; } 
    } 
} 

XAML

這裏10

<DockPanel> 
    <DockPanel LastChildFill="True"> 
     <Label DockPanel.Dock="top" Content="Title " HorizontalAlignment="Center"></Label> 
     <StatusBar DockPanel.Dock="Bottom"> 
      <StatusBarItem Content="Status Bar" ></StatusBarItem> 
     </StatusBar> 
     <Grid DockPanel.Dock="Top"> 
      <Grid.ColumnDefinitions> 
       <ColumnDefinition/> 
       <ColumnDefinition Width="Auto"/> 
       <ColumnDefinition Width="2*"/> 
      </Grid.ColumnDefinitions> 
      <TreeView Name="tree" ItemsSource="{Binding Continents}"> 
       <TreeView.ItemContainerStyle> 
        <Style TargetType="{x:Type TreeViewItem}"> 
         <Setter Property="IsExpanded" Value="{Binding IsExpanded,Mode=TwoWay}"/> 
         <Setter Property="IsSelected" Value="{Binding IsSelected,Mode=TwoWay}"/> 
         <Setter Property="FontWeight" Value="Normal"/> 
         <Style.Triggers> 
          <Trigger Property="IsSelected" Value="True"> 
           <Setter Property="FontWeight" Value="Bold"></Setter> 
          </Trigger> 
         </Style.Triggers> 
        </Style> 
       </TreeView.ItemContainerStyle> 

       <TreeView.Resources> 
        <HierarchicalDataTemplate DataType="{x:Type ViewModels:ContinentViewModel}" 
             ItemsSource="{Binding Children}"> 
         <StackPanel Orientation="Horizontal"> 
          <Image Width="16" Height="16" Margin="3,0" Source="Images\Continent.png"/> 
          <TextBlock Text="{Binding ContinentName}"/> 
         </StackPanel> 
        </HierarchicalDataTemplate> 

        <HierarchicalDataTemplate DataType="{x:Type ViewModels:CountryViewModel}" 
             ItemsSource="{Binding Children}"> 
         <StackPanel Orientation="Horizontal"> 
          <Image Width="16" Height="16" Margin="3,0" Source="Images\Country.png"/> 
          <TextBlock Text="{Binding CountryName}"/> 
         </StackPanel> 
        </HierarchicalDataTemplate> 
        <DataTemplate DataType="{x:Type ViewModels:CityViewModel}" > 
         <StackPanel Orientation="Horizontal"> 
          <Image Width="16" Height="16" Margin="3,0" Source="Images\City.png"/> 
          <TextBlock Text="{Binding CityName}"/> 
         </StackPanel> 
        </DataTemplate> 
       </TreeView.Resources> 
      </TreeView> 
      <GridSplitter Grid.Row="0" Grid.Column="1" Background="LightGray" 
       Width="5" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"/> 
      <Grid Grid.Column="2" Margin="5" > 
       <TabControl>         
        <TabItem Header="Details" DataContext="{Binding Path=SelectedItem.City, ElementName=tree, Mode=OneWay}"> 
         <StackPanel > 
          <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding CityName}"/> 
          <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding Area}"/> 
          <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding Population}"/> 
          <!-- DONT WORK WHY--> 
          <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding SelectedItem.CityDetailsInfo.ClubsCount}"/> 
          <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding SelectedItem.CityDetailsInfo.PubsCount}"/> 
         </StackPanel> 
        </TabItem> 
       </TabControl> 
      </Grid> 
     </Grid> 
    </DockPanel>  
</DockPanel> 

Answer 1

看（無關位省略掉）：

<TabItem DataContext="{Binding Path=SelectedItem.City, ElementName=tree, Mode=OneWay}"> 
    <StackPanel > 
    <!-- DONT WORK WHY--> 
    <TextBlock Text="{Binding SelectedItem.CityDetailsInfo.ClubsCount}"/> 
    <TextBlock Text="{Binding SelectedItem.CityDetailsInfo.PubsCount}" /> 
    </StackPanel> 
</TabItem> 

在DataContext的TabItem的是SelectedItem.City：那就是，在DataContext是一個城市。 City沒有SelectedItem屬性。將您的綁定更改爲例如

<TextBlock Text="{Binding CityDetailsInfo.ClubsCount}" /> 

即開始從當前的DataContext的路徑，在這種情況下，市對象。

作爲提示，「Visual Studio輸出」窗口顯示綁定錯誤，通常可以提供足夠的信息來立即診斷此錯誤。如果你看到「City」上沒有找到「Property'SelectedItem'」，那很明顯WPF沒有看着你認爲它正在看的對象！