6.2.0 Cannot call function in Class - worked flawlessly with SDK 4.2.4

Cannot call function    curRadarBattery = myBikeRadarListener.getMyBattery();   

import Toybox.Activity;
import Toybox.Lang;
import Toybox.Time;
import Toybox.WatchUi;
import Toybox.AntPlus;


var myRadarBattery = 0;
class myBikeRadarListener extends AntPlus.BikeRadarListener {

    function initialize() {
        AntPlus.BikeRadarListener.initialize();
    }

    function onBatteryStatusUpdate(data) {
        if ( data != null ) {
            if ( data.batteryStatus != null ) {
                myRadarBattery = data.batteryStatus; 
            }
        } else {    
            myRadarBattery = 0;            
        }
    }

    function getMyBattery() {
        return myRadarBattery;
    }    

}


class RadarBatteryView extends WatchUi.SimpleDataField {

    var radarlistener;
    var bikeRadar;
    var curRadarBattery = 0;
    var radarBatStatus = "unknown";


    // Set the label of the data field here.
    function initialize() {
        SimpleDataField.initialize();

        label = "Radar Battery";

        radarlistener = new myBikeRadarListener();
        bikeRadar = new AntPlus.BikeRadar(radarlistener);

    }

    function compute(info as Activity.Info) as Numeric or Duration or String or Null {

        curRadarBattery = myBikeRadarListener.getMyBattery();    
 
        //for testing:
        //curRadarBattery = 3;

        if ( curRadarBattery == 0 ) {
            radarBatStatus = "unknown";
        } else if ( curRadarBattery == 1 ) {
            radarBatStatus = "new";             // 100%
        } else if ( curRadarBattery == 2 ) {
            radarBatStatus = "good";             // 75%
        } else if ( curRadarBattery == 3 ) {
            radarBatStatus = "okay";             // 50%
        } else if ( curRadarBattery == 4 ) {
            radarBatStatus = "low";             // 30%
        } else if ( curRadarBattery == 5 ) {
            radarBatStatus = "critcal";             // 10%
        } else if ( curRadarBattery == 7 ) {
            radarBatStatus = "invalid";           
        } else if ( curRadarBattery == 8 ) {
            radarBatStatus = "cnt?";
        }

        return radarBatStatus;
    }

}