LibGDX - Get Swipe Up or swipe right etc.?

This explain a very good way to implement a system to detect the direction of a swipe. I'll post it here because the article may be lost in the future:

Create a class name SimpleDirectionGestureDetector

public class SimpleDirectionGestureDetector extends GestureDetector {
public interface DirectionListener {
    void onLeft();

    void onRight();

    void onUp();

    void onDown();
}

public SimpleDirectionGestureDetector(DirectionListener directionListener) {
    super(new DirectionGestureListener(directionListener));
}

private static class DirectionGestureListener extends GestureAdapter{
    DirectionListener directionListener;

    public DirectionGestureListener(DirectionListener directionListener){
        this.directionListener = directionListener;
    }

    @Override
    public boolean fling(float velocityX, float velocityY, int button) {
        if(Math.abs(velocityX)>Math.abs(velocityY)){
            if(velocityX>0){
                    directionListener.onRight();
            }else{
                    directionListener.onLeft();
            }
        }else{
            if(velocityY>0){
                    directionListener.onDown();
            }else{                                  
                    directionListener.onUp();
            }
        }
        return super.fling(velocityX, velocityY, button);
    }

}

}

On the create() function of the LibGdx application, put this to activate gesture handling for your game:

Gdx.input.setInputProcessor(new SimpleDirectionGestureDetector(new SimpleDirectionGestureDetector.DirectionListener() {

@Override
public void onUp() {

}

@Override
public void onRight() {

}

@Override
public void onLeft() {

}

@Override
public void onDown() {

}
}));