Swiching screen at collision LIBGDX

Question

I am programming with LIBGDX and I am working with a piece of code. What I want to happen is that when the BUCKET collides with a DROP the game switches screens back to the menuScreen. I have tried to do it as you will see in the code but when the bucket collides with a drop nothing happens. Please Help me on how to fix this. Here is all the code:

DROP CLASS:

public class Drop extends Game{

public SpriteBatch batch;
public BitmapFont font;

public void create() {
    batch = new SpriteBatch();
    //Use LibGDX's default Arial font.
    font = new BitmapFont();
    this.setScreen(new MenuScreen(this));
}

public void render() {
    super.render(); //important!
}

public void dispose() {
    batch.dispose();
    font.dispose();
}


}

MENU SCREEN CLASS:

public class MenuScreen implements Screen {

final Drop game;

OrthographicCamera camera;

public MenuScreen(final Drop gam) {
    game = gam;

    camera = new OrthographicCamera();
    camera.setToOrtho(false, 800, 480);

}

@Override
public void render(float delta) {
     Gdx.gl.glClearColor(0, 0, 0.2f, 1);
     Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);

        camera.update();
        game.batch.setProjectionMatrix(camera.combined);

        game.batch.begin();
        game.font.draw(game.batch, "Welcome to Drop!!! ", 100, 150);
        game.font.draw(game.batch, "Tap anywhere to begin!", 100, 100);
        game.batch.end();

        if (Gdx.input.isTouched()) {
            game.setScreen(new GameScreen(game));
            dispose();
        }       
}

@Override
public void resize(int width, int height) {
    // TODO Auto-generated method stub

}

@Override
public void show() {
    // TODO Auto-generated method stub

}

@Override
public void hide() {
    // TODO Auto-generated method stub

}

@Override
public void pause() {
    // TODO Auto-generated method stub

}

@Override
public void resume() {
    // TODO Auto-generated method stub

}

@Override
public void dispose() {
    // TODO Auto-generated method stub

}



}

GAME SCREEN CLASS:

public class GameScreen implements Screen {

Texture dropImage;
Texture bucketImage;
Sound dropSound;
Music rainMusic;
MenuScreen menuScreen;
Drop game;
OrthographicCamera camera;
SpriteBatch batch;
Rectangle bucket;
Array<Rectangle> raindrops;
long lastDropTime;
boolean isBucketJumping;
float bucketYSpeed = 1;
float GRAVITY = 1;



public GameScreen(final Drop gam) { 
    this.game = gam;
    // load the image for the droplet and the bucket, 48X48 pixels each
    dropImage = new Texture(Gdx.files.internal("cloud100.png"));
    bucketImage = new Texture(Gdx.files.internal("plane100.png"));

    //load the drop sound effect and the rain background "music"
    dropSound = Gdx.audio.newSound(Gdx.files.internal("drop.wav"));
    rainMusic = Gdx.audio.newMusic(Gdx.files.internal("rain.mp3"));

    //start the playback of the background music immediately
    rainMusic.setLooping(true);
    rainMusic.play();

    menuScreen = new MenuScreen(game);

    camera = new OrthographicCamera();
    camera.setToOrtho(false,800,480);

    batch = new SpriteBatch();

    bucket = new Rectangle();
    bucket.x = 250;
    bucket.y= 200;
    bucket.width = 100;
    bucket.height = 100;    


    raindrops = new Array<Rectangle>();
    spawnRaindrop();
}


@Override
public void render(float delta) {
    Gdx.gl.glClearColor(0x64/255.0f, 0x95/255.0f, 0xed/255.0f, 
             0xff/255.0f);
    Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);

    if(Gdx.input.isTouched())
    {
    bucketJump();
    }
    moveBucket();
    camera.update();

    batch.setProjectionMatrix(camera.combined);
    batch.begin();
    batch.draw(bucketImage,bucket.x,bucket.y);
    for(Rectangle raindrop: raindrops){
        batch.draw(dropImage,raindrop.x,raindrop.y);
    }
    batch.end();

    if(TimeUtils.nanoTime() - lastDropTime > 2000000000) spawnRaindrop(); 

    moveRainDrop();     
}

public void bucketJump(){
    isBucketJumping = true;
    bucketYSpeed = 7;
}

public void moveBucket(){

       bucket.y += bucketYSpeed;
       bucketYSpeed -= GRAVITY;

}



@Override
public void dispose() {
    dropImage.dispose();
    bucketImage.dispose();
    dropSound.dispose();
    rainMusic.dispose();
    batch.dispose();
}



private void moveRainDrop() {
    Iterator<Rectangle> iter = raindrops.iterator();
    while(iter.hasNext()){
        Rectangle raindrop = iter.next();
        raindrop.x -= 200 * Gdx.graphics.getDeltaTime();
        if(raindrop.x + 48 < 0) iter.remove();

        if(raindrop.overlaps(bucket)){
            dropSound.play();
            menuScreen.show();
        }
    }
}



private void spawnRaindrop(){
    Rectangle raindrop = new Rectangle();
    raindrop.y = MathUtils.random(0,450-48);
    raindrop.x = 800;
    raindrop.width = 110;
    raindrop.height = 100;
    raindrops.add(raindrop);
    lastDropTime = TimeUtils.nanoTime();
}




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

@Override
public void pause() {
}

@Override
public void resume() {
}
@Override
public void show() {

}
@Override
public void hide() {
}
}

Answer 1

In your GameScreen class do not initialize a new MainMenuScreen object in the constructor. Instead, when the drop collides with the bucket, call a method called returnToMain() or something like that, and within that method, initialized a new MainMenuScreen object and assign it to the game's screen: this.game.setScreen(new MainMenuScreen(game)). This is how I would do this, given your project's setup.