How to make binding from user control to property of parent control? - wpf

Question

I've seen similar questions, but I still not able to do my need. I need to output checkbox's name through a label inside a user control:
Window1.xaml:
<Window x:Class="WpfBinding.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfBinding" Title="Window1" Height="300" Width="300">
<Grid>
<CheckBox Name="checkBox1">
<local:UserControl1></local:UserControl1>
</CheckBox>
</Grid>
</Window>
UserControl1.xaml:
<UserControl x:Class="WpfBinding.UserControl1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Canvas>
<Label Content="{Binding ElementName=checkBox1, Path=Name}"></Label>
</Canvas>
</UserControl>
How to do it correctly? What lack of knowledge I have? Thanks for help.

Answer 1

Above solution will work, but a more direct solution for this specific problem would be to use RelativeSource binding in your user control as below:
<Canvas>
<Label Content="{Binding RelativeSource={RelativeSource AncestorType=CheckBox, AncestorLevel=1}, Path=Name}"></Label>
</Canvas>
Hope this is what you need !!!

Answer 2

ElementName binding works within in same XAML scope. This will work -
<Grid>
<CheckBox Name="checkBox1"/>
<Label Content="{Binding ElementName=checkBox1, Path=Name}"/>
</Grid>
But if you want to do it in different UserControl, you have to tweak a bit your code and use Tag to hold name -
<Grid>
<CheckBox Name="checkBox1">
<local:UserControl1 Tag="{Binding ElementName=checkBox1, Path=Name}"/>
</CheckBox>
</Grid>
UserControl.xaml
<Canvas>
<Label Content="{Binding Path=Tag, RelativeSource={RelativeSource
Mode=FindAncestor, AncestorType=UserControl}}"/>
</Canvas>
On a sidenote, in your UserControl, you know you need to bind with ElementName = checkBox1 and that's the name only you are binding to. Its something equivalent to -
<Label Content="checkBox1"/>