public synchronized void showAll() {
        for (Map.Entry<K, Pair<GeoItem, Boolean>> entry : this.itemMap.entrySet()) {
            if (!entry.getValue().second) {
                entry.setValue(new Pair<>(entry.getValue().first, true));
                putToMap(entry.getKey(), entry.getValue().first, null);
            }
        }
    }
All objects in this layer are made visible
main/src/main/java/cgeo/geocaching/unifiedmap/geoitemlayer/GeoItemLayer.java