private void setCanvas(CargoManifest cargo) {
        if (canvas != null) {
            pnlDisplay.remove(canvas);
        }
        if (cargo == null) {
            disableButtons();
        } else {
            canvas = new CargoTextArea(cargo);
            //implementation here
            canvas.setBackground(Color.DARK_GRAY);
            pnlDisplay.add(canvas);
            this.add(pnlDisplay, BorderLayout.NORTH);
            enableButtons();
        }
        redraw();
    }