为什么GameScreen会旋转180度？

Question

我正在制作基于Libgdx框架的Box2D游戏。 当我从MenuScreen导航到GameScreen我的GameScreen旋转180度。 我谷歌，但我找不到任何解决方案。 这是我的代码：

Menuscreen：

private static final String TAG = MenuScreen.class.getName();

private Stage stage;
private Skin skinMenuScreen;
//private Skin skinLibgdx;

// menu
private Image imgBackground;
private Image imgControlContainer;
private TextButton btnStartGame;



// debug
private final float DEBUG_REBUILD_INTERVAL = 5.0f;
private boolean debugEnabled = false;
private float debugRebuildStage;

public MenuScreen(Game game) {
    super(game);
    //onStartClicked();
}

@Override
public void render(float deltaTime) {
    Gdx.gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
    //rebuildStage();//you rebuild your stage inside render method?
    stage.act(deltaTime);
    stage.draw();
}

@Override
public void resize(int width, int height) {
    stage.getViewport().update(width, height);
}

@Override
public void show() {
    stage = new Stage();
    Gdx.input.setInputProcessor(stage);
    rebuildStage();
}

@Override
public void hide() {
    stage.dispose();
    skinMenuScreen.dispose();
    //skinLibgdx.dispose();
}

@Override
public void pause() {

}

private void rebuildStage () {
    skinMenuScreen = new Skin(Gdx.files.internal(AppConstant.SKIN_MENU_SCREE_UI), new TextureAtlas(AppConstant.TEXTURE_ATLAS_UI));
    //skinLibgdx = new Skin(Gdx.files.internal(AppConstant.SKIN_LIBGDX_UI), new TextureAtlas(AppConstant.TEXTURE_ATLAS_LIBGDX_UI));

    // build all layers
    Table layerBackground = buildBackgroundLayer();
    Table layerContolContainer = buildCantainer();
    Table layerStartControls = buildStartControlsLayer();

    // assemble stage for menu screen
    stage.clear();
    Stack stack = new Stack();
    stage.addActor(stack);
    stack.setSize(AppConstant.VIEWPORT_GUI_WIDTH, AppConstant.VIEWPORT_GUI_HEIGHT);
    stack.add(layerBackground);
    stack.add(layerContolContainer);
    stack.add(layerStartControls);
}

private Table buildBackgroundLayer () {
    Table layer = new Table();
    // + Background
    imgBackground = new Image(skinMenuScreen, "welcome");
    layer.add(imgBackground);
    return layer;
}

private Table buildTitle()
{
    Table layer = new Table();
    layer.center().top();
    layer.padTop(40);
    // + Title
    BitmapFont bitmapFont = Assets.instance.fonts.bitmapFont;
    LabelStyle lblStyle = new LabelStyle(bitmapFont, Color.WHITE);
    lblTitle= new Label("Jungle Monkey", lblStyle);
    layer.add(lblTitle);
    return layer;
}

private Table buildStartControlsLayer()
{
    Table layer = new Table();
    // + Sound
    TextButtonStyle textButtonStyle = new TextButtonStyle();
    BitmapFont bitmapFont = Assets.instance.fonts.bitmapFont;
    textButtonStyle.font = bitmapFont;
    textButtonStyle.fontColor = Color.DARK_GRAY;
    bitmapFont.setScale(1.0F);
    textButtonStyle.up = skinMenuScreen.getDrawable("menu-2");
    textButtonStyle.down = skinMenuScreen.getDrawable("menu-2");
    btnStartGame = new TextButton("Start", textButtonStyle);
    layer.addActor(btnStartGame);
    btnStartGame.setPosition((AppConstant.VIEWPORT_GUI_WIDTH - 230), 100);
    btnStartGame.setSize(150, 50);

    btnStartGame.addListener(new ChangeListener() {
        @Override
        public void changed (ChangeEvent event, Actor actor) {
            onStartClicked();
        }
    });

    layer.add(btnStartGame);
    return layer;
}

private void onStartClicked()
{
    System.out.println("clicked");
    game.setScreen(new GameScreen(game));
    System.out.println("clicked");
}

@Override
public InputProcessor getInputProcessor() {
    return null;
}

GameScreen

public class GameScreen extends AbstractGameScreen 
    {

    private static final String TAG = GameScreen.class.getName();
    private WorldController worldController;
    private WorldRenderer worldRenderer;

    private boolean paused;

    public GameScreen(Game game) {
        super(game);
    }

    @Override
    public void render(float deltaTime) {

        // Do not update game world when paused.
        if (!paused) {
            // Update game world by the time that has passed
            // since last rendered frame.
            worldController.update(deltaTime);
        }

        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
        // Render game world to screen
        worldRenderer.render();
    }

    @Override
    public void resize(int width, int height) {
        worldRenderer.resize(width, height);
    }

    @Override
    public void show() {
        worldController = new WorldController(game);
        worldRenderer = new WorldRenderer(worldController);
    }

    @Override
    public void hide() {
        worldRenderer.dispose();
    }

    @Override
    public void pause() {
        paused = true;
    }

    @Override
    public void resume () {
        super.resume();
        // Only called on Android!
        paused = false;
    }

    @Override
    public InputProcessor getInputProcessor () {
        return worldController;
    }
}

感谢任何帮助。 感谢。