Question

I am new to WPF, and trying to develop a small application using DataBinding following the MVVM paradigm.

I am trying to provide a binding functionality to the ObservableCollection of Documents (my type). The First Label would display a Documents path (available through Attribute property), while the next children – Pages of the Documents – would display appropriate information: page index and page content (an image).

Here is an issue – how can I create a lookup binding to a parent Label? On Button Click command I would like to pass the documents path, which was available earlier in the first DataTemplate.

Is there a way to tackle this issue?
How would you recommend going around it?

Also, is there a better way to tackle “nested” structures (collections within collections)?

Here is the code https://gist.github.com/b5760982ba81e8ee4036, line 14

Answer 1

you should use RelativeSource:

<ItemsControl ItemsSource="{Binding Documents}">
<ItemsControl.ItemTemplate>
    <DataTemplate>
        <StackPanel>
            <Label Content="{Binding Path=Attribute.Path}"/>
                <ItemsControl ItemsSource="{Binding Pages}">
                    <ItemsControl.ItemTemplate>
                        <DataTemplate>
                            <StackPanel>




<Label Content="{Binding Index}"/>
                                <Button Content="{Binding Content}"
                                        Command="{x:Static viewModel:DocViewModel.Tests }" 
                                        CommandParameter="{Binding Path=DataContext.Attribute.Path,RelativeSource={RelativeSource AncestorType=ContentPresenter, Mode=FindAncestor,AncestorLevel=2"/> 
                            </StackPanel>
                        </DataTemplate>
                    </ItemsControl.ItemTemplate>
                </ItemsControl>
            </StackPanel>
        </DataTemplate>
    </ItemsControl.ItemTemplate>