public class BoxScreen extends HandledScreen<ScreenHandler> {
    private static final Identifier TEXTURE = new Identifier("minecraft", "textures/gui/container/dispenser.png");

    public BoxScreen(ScreenHandler handler, PlayerInventory inventory, Text title) {
        super(handler, inventory, getPositionText(handler).orElse(title));
        //We try to get the block position to use it as our title, if that fails for some reason we will use the default title
    }

    //This method will try to get the Position from the ScreenHandler, as ScreenRendering only happens on the client we
    //get the ScreenHandler instance here which has the correct BlockPos in it!
    private static Optional<Text> getPositionText(ScreenHandler handler) {
        if (handler instanceof BoxScreenHandler) {
            BlockPos pos = ((BoxScreenHandler) handler).getPos();
            // for versions 1.18.2 and below, use `new LiteralText`
            return pos != null ? Optional.of(Text.literal("(" + pos.toShortString() + ")")) : Optional.empty();
        } else {
            return Optional.empty();
        }
    }


    @Override
    protected void drawBackground(MatrixStack matrices, float delta, int mouseX, int mouseY) { [...] }

    @Override
    public void render(MatrixStack matrices, int mouseX, int mouseY, float delta) { [...] }

    @Override
    protected void init() { [...] }
}