DroidAR Library地理定位问题

Question

我想在我的项目中使用DroidAR库，但示例代码不起作用 https://github.com/bitstars/droidar/wiki/Example-code-how-to-create-an-object-with-GPS-coordinates-and-display-its-distance 我在我的项目中使用此代码

^

    public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Button button = new Button(this);
        button.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                ArActivity.startWithSetup(MainActivity.this,
                        new DefaultARSetup() {

                            @Override
                            public void addObjectsTo(GL1Renderer renderer,
                                    final World world, GLFactory objectFactory) {
                                Location l = new Location("");
                                l.setLatitude(51.533144);
                                l.setLongitude(46.038401);

                                Obj o = new GeoObj(l);

                                o.setComp(objectFactory.newCube());
                                o.setComp(new Entity() {

                                    private Updateable p;
                                    private float waitTimeInMilliseconds = 1000;
                                    UpdateTimer timer = new UpdateTimer(
                                            waitTimeInMilliseconds, null);

                                    @Override
                                    public boolean accept(Visitor visitor) {
                                        return false;
                                    }

                                    @Override
                                    public boolean update(float timeDelta,
                                            Updateable parent) {
                                        p = parent;
                                        if (timer.update(timeDelta, parent)) {
                                            // true once a second, do the
                                            // calculation here:
                                            float distanceOfGeoObjToUser = Vec.distance(
                                                    ((GeoObj) p)
                                                            .getVirtualPosition(),
                                                    world.getMyCamera()
                                                            .getPosition());
                                            Log.d("dist",
                                                    String.valueOf(distanceOfGeoObjToUser));
                                        }
                                        return true;
                                    }

                                    @Override
                                    public void setMyParent(Updateable parent) {
                                        this.p = parent;
                                    }

                                    @Override
                                    public Updateable getMyParent() {
                                        return p;
                                    }
                                });
                                world.add(o);
                            }
                        });
            }
        });
        setContentView(button);
    }
}

正在加载应用程序，但不显示任何内容 但在日志中我看到了这个

Current location was unknown, cant do steps