private void clearTrailHistory() {
        DataStore.clearTrailHistory();
        overlayPositionAndScale.setHistory(new ArrayList<>());
        mapView.repaintRequired(overlayPositionAndScale instanceof GeneralOverlay ? ((GeneralOverlay) overlayPositionAndScale) : null);
        ActivityMixin.showToast(activity, res.getString(R.string.map_trailhistory_cleared));
    }
Set the zoom of the map. The zoom is restricted to a certain minimum in case of live map.
main/src/main/java/cgeo/geocaching/maps/CGeoMap.java