JScrollpane占用整个Jframe

Question

我正在尝试为任务列表创建一个表单，该表格将在jscrollpane中具有一系列任务列表，其下面有一些按钮，从本质上讲是这样的：

我遇到的问题是滚动窗格似乎正在接管整个框架，我看不到按钮。我正在制作一个更简单的原型，以试图弄清楚我在做什么错，但我似乎没有什么可用。

有人可以帮助我包含JSCrollpane的大小吗？

public class Test extends JFrame {

    private JLabel label1 = new JLabel();
    private JLabel label2 = new JLabel();
    private JLabel[] titles;
    private JLabel[] descriptions;
    private JPanel[] panels;
    private JCheckBox[] boxes;
    private JScrollPane jScrollPane1;
    private JPanel bigPanel;
    private final static int NUM_OF_RESULTS = 10;

    public Test() {

        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setPreferredSize(new Dimension(1000, 600));

        bigPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
        //set layout to
        GridLayout layout = new GridLayout(30, 30);
        bigPanel.setLayout(layout);
        jScrollPane1 = new JScrollPane(bigPanel);
        jScrollPane1.setPreferredSize(new Dimension(500, 300));
        getContentPane().add(jScrollPane1);

        // How do I get these buttons to show on the main panel?
        // JButton button1 = new JButton("Save");
        // JButton button1 = new JButton("Cancel");
        // getContentPane.add(button1);
        // getContentPane.add(button2);

        scrollPanelDemo();
        pack();
        setVisible(true);
    }

    public void scrollPanelDemo() {

        titles = new JLabel[NUM_OF_RESULTS];
        descriptions = new JLabel[NUM_OF_RESULTS];
        panels = new JPanel[NUM_OF_RESULTS];
        boxes = new JCheckBox[NUM_OF_RESULTS];

        for (int i = 0; i < NUM_OF_RESULTS; i++) {

            String title = "Test Title " + i;
            String resume = "Test Resume " + i;

            titles[i] = new JLabel();
            boxes[i] = new JCheckBox();
            panels[i] = new JPanel();
            boxes[i].setPreferredSize(new Dimension(50, 50));
            panels[i].setPreferredSize(new Dimension(500, 50));
            panels[i].setLayout(new FlowLayout()); //FlowLayout is default for JPanel
            titles[i].setText(title);
            titles[i].setPreferredSize(new Dimension(500, 50));

            panels[i].add(boxes[i]);
            panels[i].add(titles[i]);
            bigPanel.add(panels[i], i, 0);
        }
    }

    public static void main(String args[]) {
        new Test();
    }
}