[SailfishDevel] Prototype 'TextBaseItem' from 'TextBase' could not be resolved (M301)

[info at flyingfischer.ch]

Hello

The IDE gives me en error on the "TextField" element. I couldn't find 
anything to resolve it.

Thank you for your inputs!
Markus

[Translated to english from the german error message:]
Prototype 'TextBaseItem' from 'TextBase' could not be resolved (M301)

This is the page structure I use:

import QtQuick 2.0
import Sailfish.Silica 1.0


Page {
     id: myPage

     SilicaFlickable {
         id: flick
...

         Column {
             id: contentColumn
...

             PageHeader {
                 title: "My Title"
             }

             TextField {
                 id:textEditor
...
             }
         }
     }
}