Migrate Vaadin 8 to 14: Widgetset 'xx.MyAppWidgetset' does not contain an implementation for com.vaadin.mpr.MprUIContent

Question

We are migrating from Vaadin 8 to Vaadin Flow 14. In order to migrate piece by piece, MPR is used. We use Flow 14's Route for navigation. For each view we created a MprRouteAdapter. This is proved a nice approach in a small project, but when we move to relatively bigger project with some addons, navigating to a view shows the following message and the view does not show:

Widgetset 'xx.MyAppWidgetset' does not contain an implementation for 
com.vaadin.mpr.MprUIContent. Check the connector's @Connect mapping, the widgetset's GWT module 
description file and re-compile your widgetset. In case you have downloaded a vaadin add-on 
package, you might want to refer to add-on instructions.

Below is MyAppWidgetset.gwt.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 2.5.1//EN"
    "http://google-web-toolkit.googlecode.com/svn/tags/2.5.1/distro-source/core/src/gwt-module.dtd">
<module>
    <inherits name="com.vaadin.DefaultWidgetSet"/>
    <inherits name="com.vaadin.mpr.MprWidgetSet" />

    <inherits name="org.vaadin.addons.WidgetSet" />
    
    <inherits name="org.vaadin.risto.formsender.widgetset.FormSenderWidgetset" />

    <inherits name="org.vaadin.hene.popupbutton.widgetset.PopupbuttonWidgetset" />


    <inherits name="org.tepi.listbuilder.WidgetSet" />

    <inherits name="com.vaadin.addon.onoffswitch.WidgetSet" />

    <inherits name="org.vaadin.addon.leaflet.Widgetset" />

</module>

The goal update-widgetset and compile have been added in maven build file.

Do I miss anything? Please help me to figure out the issue.

Thanks in advance.

Answer 1

The issue is resolved by removing MyAppWidgetset.gwt.xml and annotation @MprWidgetset.