In API documentation (and also in SDK) it is:
getBikeLights() as Lang.Array<AntPlus.LightNetworkState> or Null
But it returns an Array of BikeLight.
When type check level is set to strict you need to do a lot of workaround code to handle this.
Like:
mBikeLights = mLightNetwork.getBikeLights();
var bikeLights = mBikeLights as Array;
for (var i = 0; i < bikeLights.size(); i++) {
var light = bikeLights[i] as BikeLight?;