Setting a CommandTarget for the selected control in TabControl

Question

I have a WPF window with several buttons and a tabcontrol with a tab for each "document" the user is working on. Tabcontrol uses a DataTemplate to visualize data in an ItemSource tabcontrol.

Question: If one of the buttons is pressed, the command must be executed in the control that displays the document on the active tab, but I have no idea why the CommandTarget should be installed. I tried {Binding ElementName = nameOfControlInDataTemplate}, but this clearly does not work.

I tried to make my problem more abstract with the following code (ItemSource and Document objects are not saved, but the idea is the same).

<Button Command="ApplicationCommands.Save" CommandTarget="{Binding ElementName=nestedControl}">Save</Button>
<TabControl x:Name="tabControl">
    <TabControl.Items>
        <TabItem Header="Header1">Item 1</TabItem>
        <TabItem Header="Header2">Item 2</TabItem>
        <TabItem Header="Header3">Item 3</TabItem>
    </TabControl.Items>
    <TabControl.ContentTemplate>
        <DataTemplate>
            <CommandTest:NestedControl Name="nestedControl"/>
        </DataTemplate>
    </TabControl.ContentTemplate>
</TabControl>

, tabcontrol NestedControl, .

, NestedControl:

<UserControl x:Class="CommandTest.NestedControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Grid>
        <Label x:Name="label" Content="Not saved"/>
    </Grid>
</UserControl>

:

public partial class NestedControl : UserControl {
    public NestedControl() {
        CommandBindings.Add(new CommandBinding(ApplicationCommands.Save, CommandBinding_Executed));
        InitializeComponent();
    }

    private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e) {
        label.Content = "Saved";
    }
}

Answer 1

, CommandTarget, TabControl :

"{Binding ElementName=tabControl,Path=SelectedItem}"

(SelectedItem - )

EDIT:

CommandTarget : XAML

2:

, .