Why when i use ContentPresenter in DataTemplate bindings do not works?

[Dyikot]

But when i use ContentControl all works.
For example:

<DataTemplate DataType="{x:Type vm:Query.QueryViewModel}"> 
  <ContentPresenter Content="{Binding OperatorViewModel}" /> <!--{Binding OperatorIndex} does NOT work -->
  <ContentControl Content="{Binding OperatorViewModel}" />   <!--{Binding OperatorIndex} does work -->
  <!-- other code-->
</DateTemplate>

<DataTemplate DataType="{x:Type vm:Query.QueryOperatorViewModel}">
  <ComboBox SelectedIndex="{Binding OperatorIndex}" CornerRadius="3" Width="80">
    <ComboBoxItem Content="{x:Static loc:Resource.And}" />
    <ComboBoxItem Content="{x:Static loc:Resource.Or}" />
    <ComboBoxItem Content="{x:Static loc:Resource.Not}" />
  </ComboBox>
</DataTemplate>

[thevortexcloud]

From memory, ContentPresenter is meant to be used in control templates only, not data templates. The WPF docs explain this (and as far as I am aware the same applies to Avalonia):

You typically use the ContentPresenter in the ControlTemplate of a ContentControl to specify where the content is to be added. Every ContentControl type has a ContentPresenter in its default ControlTemplate.

When a ContentPresenter object is in a ControlTemplate of a ContentControl, the Content, ContentTemplate, and ContentTemplateSelector properties get their values from the properties of the same names of the ContentControl. You can have the ContentPresenter property get the values of these properties from other properties of the templated parent by setting the ContentSource property or binding to them.

https://learn.microsoft.com/en-us/dotnet/api/system.windows.controls.contentpresenter?view=windowsdesktop-9.0

[timunie]

Yes exactly. Use ContentControl instead