A controller manager for the Conductor library

ControllerManager.java

import android.os.Bundle;
import android.os.Parcelable;
import android.support.annotation.NonNull;
import android.util.SparseArray;
import android.view.ViewGroup;

import com.bluelinelabs.conductor.Controller;
import com.bluelinelabs.conductor.Router;
import com.bluelinelabs.conductor.RouterTransaction;

public class ControllerManager {

    private static final String KEY_SAVED_PAGES = "ControllerManager.savedStates";
    private static final String KEY_CURRENT_ROUTER_ID = "ControllerManager.routerId";

    private final Controller host;
    private final ViewGroup container;

    private SparseArray<Bundle> savedPages = new SparseArray<>();
    private int currentRouterId = -1;

    public ControllerManager(@NonNull Controller host, ViewGroup container) {
        this.host = host;
        this.container = container;
    }

    public void show(@NonNull Controller controller, int id) {
        final String currentRouterTag = getRouterTag(currentRouterId);
        if (!getRouterTag(id).equals(currentRouterTag)) {
            if (currentRouterId != -1) {
                destroyItem(currentRouterId, host.getChildRouter(container, currentRouterTag));
            }
            instantiateItem(controller, id);
        }
    }

    private void instantiateItem(Controller controller, int id) {
        final String tag = getRouterTag(id);

        Router router = host.getChildRouter(container, tag);
        if (!router.hasRootController()) {
            Bundle routerSavedState = savedPages.get(id);

            if (routerSavedState != null) {
                router.restoreInstanceState(routerSavedState);
            }
        }

        router.rebindIfNeeded();

        if (!router.hasRootController()) {
            router.setRoot(RouterTransaction.with(controller));
        }

        currentRouterId = id;
    }

    private void destroyItem(int id, Router router) {
        Bundle savedState = new Bundle();
        router.saveInstanceState(savedState);
        savedPages.put(id, savedState);

        host.removeChildRouter(router);
    }

    public Parcelable saveState() {
        Bundle bundle = new Bundle();
        bundle.putSparseParcelableArray(KEY_SAVED_PAGES, savedPages);
        bundle.putInt(KEY_CURRENT_ROUTER_ID, currentRouterId);
        return bundle;
    }

    public void restoreState(Parcelable state) {
        Bundle bundle = (Bundle) state;
        if (state != null) {
            savedPages = bundle.getSparseParcelableArray(KEY_SAVED_PAGES);
            currentRouterId = bundle.getInt(KEY_CURRENT_ROUTER_ID, -1);
        }
    }

    private String getRouterTag(int id) {
        return container.getId() + ":" + id;
    }

    public boolean handleBack() {
        return host.getChildRouter(container, getRouterTag(currentRouterId)).handleBack();
    }
}

Looks nice!
Are there any samples where you have used this?

I don't have any projects I can share, but it is currently being used in production code