MapView does not update prefCenter and prefZoom

[ctipper]

In the course of trying to integrate this as a library it has become apparent that MapView updates BaseMap coordinate and zoom via the variables prefCenterLat, prefCenterLon and prefZoom exactly once and that these variables are never updated again as the user zooms and pans the MapView. Consequently a library user has no way of persisting the state of the map and it is not really suitable to be used as a library. There are other issues in particular the private InputEvent handlers which can be worked around with EventFilters, but currently this is not suitable for my purposes.

[ctipper]

The MapView.getMapPosition appears to return lon and lat but this is not clear from variable names. I might have to withdraw this issue, but it is frustrating that there is no access to underlying BaseMap from MapView, this would allow access to the BaseMap readOnlyProperties.

[ctipper]

MapView.getZoom returns BaseMap.prefZoom so still no way to retrieve last zoom level from MapView.

[ctipper]

I've examined the options and it seems I only need in MapView

public double getMapZoom() {
    return baseMap.zoom().get();
}

I don't know the likelihood of getting a PR accepted I've never done a pull request before.

[ctipper]

For the same project I've also had need of this function in MapView

public void moveMap(double x, double y) {
        baseMap.moveX(x);
        baseMap.moveY(y);
    }