How to define UserControl with custom content?

Question

I want to define my custom decorator that has user content in it. But it always fail when I try to set some control's name. I always get this exception when trying to do it:

Cannot set Name attribute value 'butt' on element 'Button'. 'Button' is under the scope of element 'UserControl1', which already had a name registered when it was defined in another scope.

I don't understand why that happens. Here's teh codez:

<UserControl x:Class="WpfApplication5.UserControl1"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
             x:Name="control">
    <ContentPresenter Content="{Binding ElementName=control, Path=DataContext}" />
</UserControl>

<Window x:Class="WpfApplication5.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:WpfApplication5"
        Title="MainWindow" Height="350" Width="525">
    <local:UserControl1>
        <local:UserControl1.DataContext>
            <Button x:Name="butt" />
        </local:UserControl1.DataContext>
    </local:UserControl1>
</Window>

How to do that properly?

You cannot name control's inside user control, at least in WPF4. — Code0987, Jul 23 '11 at 09:30
I can if UserControl has same layout but defined programmatically (without XAML file) — Poma, Jul 23 '11 at 09:33
But XAML way it's not possible. I read somewhere which i forgot. — Code0987, Jul 23 '11 at 09:35
Does this answer your question? [How to create a WPF UserControl with NAMED content](https://stackoverflow.com/questions/751325/how-to-create-a-wpf-usercontrol-with-named-content) — StayOnTarget, Apr 17 '20 at 20:49

score 0 · Answer 1 · edited May 23 '17 at 11:55

You cannot name elements inside UserControls, someone considered this to be a bug but i do not know if this is the case, either way, this will not work. You could declare the Button as a resource of your Window and then insert it via StaticResource, then however the name will not be registered as a field in the window class.

Either way, do you really need the name?

Edit: Also see this question.

How to define UserControl with custom content?

1 Answers1