Silverlight Treeview inline HierarchicalDataTemplate綁定問題

Question

我有MyPOCO對象MyCollection（它有兩個字符串屬性）。

當我嘗試將HierarchicalDataTemplate實現到樹視圖中時，綁定不起作用，我得到類名。

我知道如果我從控制中取出數據模板一切正常，但我有興趣看看爲什麼這個例子不起作用。

<Grid x:Name="LayoutRoot" Background="White" DataContext="{Binding Source={StaticResource testVM}}"> 
    <sdk:TreeView Margin="8,8,8,111" ItemsSource="{Binding MyCollection}"> 
     <sdk:HierarchicalDataTemplate ItemsSource="{Binding MyPOCO}"> 
      <sdk:HierarchicalDataTemplate.ItemTemplate> 
       <DataTemplate> 
        <StackPanel> 
         <TextBlock Text="{Binding Property1}"/> 
         <TextBlock Text="{Binding Property2}"/> 
        </StackPanel> 
       </DataTemplate> 
      </sdk:HierarchicalDataTemplate.ItemTemplate> 
     </sdk:HierarchicalDataTemplate> 
    </sdk:TreeView> 
</Grid> 

這裏是ViewModel也。

namespace MyPOCProject 

{ 公共類MyPOCO { 私人字符串property1;

public string Property1 
    { 
     get { return property1; } 
     set { property1 = value; } 
    } 

    private string property2; 

    public string Property2 
    { 
     get { return property2; } 
     set { property2 = value; } 
    } 

    public MyPOCO(string p1, string p2) 
    { 
     property1 = p1; 
     property2 = p2; 
    } 
} 

public class MyViewModel : INotifyPropertyChanged 
{ 
    private ObservableCollection<MyPOCO> myCollection; 

    public ObservableCollection<MyPOCO> MyCollection 
    { 
     get { return myCollection; } 
     set { myCollection = value; RaisePropertyChanged("MyCollection"); } 
    } 

    public MyViewModel() 
    { 
     MyPOCO _poco1 = new MyPOCO("aaa1", "bbb1"); 
     MyPOCO _poco2 = new MyPOCO("aaa2", "bbb2"); 
     MyPOCO _poco3 = new MyPOCO("aaa3", "bbb3"); 

     MyCollection = new ObservableCollection<MyPOCO>() { _poco1, _poco2, _poco3 }; 
    } 

    public event PropertyChangedEventHandler PropertyChanged; 

    private void RaisePropertyChanged(string propertyName) 
    { 
     if (this.PropertyChanged != null) 
     { 
      this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); 
     } 
    } 
} 

}

那我做錯了嗎？

重新...我對這個特殊的例子感興趣。我想知道這個例子有什麼問題，爲什麼。

謝謝。

Answer 1

您發佈的代碼不是分層的，換句話說：MyPOCO類不包含屬性MyCollection<MYPOCO>兒童。 下面是HierarchicalDataTemplate

的XAML的例子：

<sdk:TreeView x:Name="MyTreeView" 
       HorizontalAlignment="Left" 
       ItemsSource="{Binding MyCollection}" 
       Width="200" Height="280"> 
    <sdk:TreeView.ItemTemplate> 
     <sdk:HierarchicalDataTemplate ItemsSource="{Binding Path=Children}"> 
      <TextBlock Text="{Binding Path=Header}"/> 
      <sdk:HierarchicalDataTemplate.ItemTemplate> 
       <sdk:HierarchicalDataTemplate ItemsSource="{Binding Path=Children}"> 
        <TextBlock Text="{Binding Path=Header}"/> 
       </sdk:HierarchicalDataTemplate> 
      </sdk:HierarchicalDataTemplate.ItemTemplate> 
     </sdk:HierarchicalDataTemplate> 
    </sdk:TreeView.ItemTemplate> 
</sdk:TreeView> 

代碼隱藏類：

public class MyPoco 
{ 
    public MyPoco(string header, int sampleChildrenCount) 
    { 
     this.Header = header; 
     this.Children = new ObservableCollection<MyPoco>(); 
     if (sampleChildrenCount > 0) 
     { 
      for (int i = 0; i < sampleChildrenCount; i++) 
      { 
       string newHeader = String.Format("Test {0}", sampleChildrenCount * i); 
       var myPoco = new MyPoco(newHeader, sampleChildrenCount - 1) 
       this.Children.Add(myPoco); 
      } 
     } 
    } 
    public string Header { get; set; } 
    public ObservableCollection<MyPoco> Children { get; set; } 
} 

public class MyViewModel 
{ 
    public MyViewModel() 
    { 
     MyCollection = new ObservableCollection<MyPoco>(); 
     for (int i = 0; i < 6; i++) 
     { 
      this.MyCollection.Add(new MyPoco(String.Format("Test {0}", i), 5)); 
     } 
    } 
    public ObservableCollection<MyPoco> MyCollection { get; set; } 
} 

代碼隱藏啓動：

public MainPage() 
{ 
    public MainPage() 
    { 
     InitializeComponent(); 
     MyTreeView.DataContext = new MyViewModel(); 
    } 
}