^{Originally posted by smalec May 2, 2024}
Hello, I'm still new in .NET MAUI so I still have some problems with basic concepts and best practices. Currently I'm struggling a bit with ContentPresenter.

So I have a custom component (ContentView) with ControlTemplate that uses ContentPresenter. Let us name this CustomControl.xaml

<ContentView>
    <ContentView.ControlTemplate>
        <ControlTemplate>
            <ContentPresenter />
        </ControlTemplate>
    </ContentView.ControlTemplate>
</ContentView>

Obviously I'm using MVVM so when I want to use CustomControl in a view I do this:

<ContentPage>
    <local:CustomControl>
        <Button Text="Click me" Command="{Binding DoSomethingCommand}" />
    </local:CustomControl>
</ContentPage>

where DoSomethingCommand is defined in my view model.

And this works perfectly fine, awesome! But what if I want to use multiple ContentPresenters in my CustomControl? As far as I know, I should bind content of ContentPresenter like this:

<ContentView>
    <ContentView.ControlTemplate>
        <ControlTemplate>
            <ContentPresenter Content="{TemplateBinding MyContent}" />
        </ControlTemplate>
    </ContentView.ControlTemplate>
</ContentView>

Of course I've defined BindableProperty in my code-behind file. And now I'm using my CustomControl like this:

<ContentPage>
    <local:CustomControl>
        <local:CustomControl.MyContent>
            <Button Text="Click me" Command="{Binding DoSomethingCommand}" />
        </local:CustomControl.MyContent>
    </local:CustomControl>
</ContentPage>

And my button shows up exactly where it should, but... there is absolutely no effect when clicking on it :( I searched for a solution and I found out that I can use it like that:

<Button Text="Click me" Command="{Binding Source={RelativeSource AncestorType={x:Type viewmodels:MyViewModel}}, Path=DoSomethingCommand}" />

And that indeed works, but it looks awful and I don't understand it at all :( Could anyone please help me understand why this simple binding to my command doesn't work? Maybe I can/should modify somehow my CustomControl?