Libgdx background and foreground in single stage

Question

My requirements:

1. Background filling entire physical screen (stretching if required)
2. Preserve aspect ratio of foreground assets (Work with virtual widt

Answer 1

You could use two stages, but for your case it would be better to just solve this problem by creating two groups inside a single stage:

Stage stage = new Stage();

Group background = new Group();
background.setBounds(0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
Group foreground = new Group();
foreground.setBounds(0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());

// Notice the order
stage.addActor(background);
stage.addActor(foreground);

foreground.addActor(new Actor());
// Or anything else you want to add like you normally would to the stage. 

background.addActor(new Image()); // your background image here.

Gdx.input.setInputProcessor(stage);