将复选框的Tag属性绑定到祖先数据上下文

Question

我知道这是一个经常出现的问题，但在查看了大量相关问题后，我仍然没有找到有效的解决方案。

我有这个主窗口

public partial class MainWindow : Window
{
public ObservableCollection<Camera> Cameras { get; set; } = new ObservableCollection<Camera>();
public ObservableCollection<Group> Groups { get; set; } = new ObservableCollection<Group>();
public MainWindow()
{
InitializeComponent();
DataContext = this;
}
}

这类

public class Group : INotifyPropertyChanged
{
private int _number;
[XmlAttribute("Number")]
public int Number
{
get { return _number; }
set
{
_number = value;
OnPropertyChanged();
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}

这是MainWindow.xaml(相关部分(的一部分

<StackPanel>
<Button Click="Button_Click_1" Margin="55,0,0,0" Padding="4">Add Group</Button>
<ListView Grid.ColumnSpan="3" Grid.Row="1" ItemsSource="{Binding Groups,Mode=TwoWay}">
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<TextBlock Margin="3" Width="30" Grid.Column="0" Text="{Binding Number}"></TextBlock>
<ComboBox Margin="3" Width="50" Grid.Column="5" ItemsSource="{Binding DataContext.Cameras, RelativeSource={RelativeSource AncestorType=ListView}}">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<CheckBox Width="20" VerticalAlignment="Center" Tag="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListView}}, Path=DataContext.Number}" Checked="OnCbObjectCheckBoxChecked" Unchecked="OnCbObjectCheckBoxChecked" />
<!--<CheckBox Width="20" VerticalAlignment="Center" Tag="{Binding Path=DataContext.Number, RelativeSource={RelativeSource AncestorType=ListView}}" Checked="OnCbObjectCheckBoxChecked" Unchecked="OnCbObjectCheckBoxChecked" />-->
<TextBlock Text="{Binding Path=Name, Mode=TwoWay}"></TextBlock>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>


</StackPanel>

组合框内的复选框列表将根据摄像机列表进行填充。我想绑定"；标记"；内部复选框的成员Groups.Number，就像我对它上面的文本块所做的那样。这背后的原因(也许你有另一个解决方案(是，组列表是一个动态组，我想确定复选框是从哪个组中选中的。我已经尝试了所有关于祖先的问题，但似乎都不起作用。我试过的其他东西是：

<CheckBox Width="20" VerticalAlignment="Center" Tag="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListView}}, Path=DataContext.Number}" Checked="OnCbObjectCheckBoxChecked" Unchecked="OnCbObjectCheckBoxChecked" />
<CheckBox Width="20" VerticalAlignment="Center" Tag="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListView}}, Path=DataContext.Groups.Number}" Checked="OnCbObjectCheckBoxChecked" Unchecked="OnCbObjectCheckBoxChecked" />
<CheckBox Width="20" VerticalAlignment="Center" Tag="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListView}}, Path=Number}" Checked="OnCbObjectCheckBoxChecked" Unchecked="OnCbObjectCheckBoxChecked" />
<CheckBox Width="20" VerticalAlignment="Center" Tag="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListView}}, Path=Groups.Number}" Checked="OnCbObjectCheckBoxChecked" Unchecked="OnCbObjectCheckBoxChecked" />

我在这里想念什么？泰！

Answer 1

ListView的wron为DataContext。它在DataTemplate之外并且被设置为MainWindow。以Group为目标的DataTemplate具有适当的DataContext，当然是当前的Group项。您必须选择此DataTemplate的一个元素作为绑定源。你可以与ComboBox.DataContext:结合

<CheckBox Tag="{Binding RelativeSource={RelativeSource AncestorType=ComboBox}, Path=DataContext.Number}" />