final JPanel operatePanel = new JPanel();
operatePanel.setLayout(new GridBagLayout());
getContentPane().add(operatePanel, BorderLayout.NORTH);
怎么给这个添加背景图片呢
final JPanel operatePanel = new JPanel();
operatePanel.setLayout(new GridBagLayout());
getContentPane().add(operatePanel, BorderLayout.NORTH);
怎么给这个添加背景图片呢