Listview inside of scrollviewer prevents scrollviewer scroll

That happens because the ListView‘s (ListBox‘s, actually) content template wraps its items with a ScrollViewer by itself.

The simplest way is to disable it by dropping your own Template for the inside ListView, one that doesn’t create a ScrollViewer:

    <ListView>
      <ListView.Template>
        <ControlTemplate>
          <ItemsPresenter></ItemsPresenter>
        </ControlTemplate>
      </ListView.Template>
      ...
    </ListView>

BTW the same happens if you have a ListView inside a ListView (this was my case).