小编use*_*353的帖子

我想在JFrame上显示2个对象.我尝试将对象添加到JPanel,然后将JPanel添加到JFrame,但它也无法正常工作.我还尝试将ball和ball1对象直接添加到JFrame,但它仅显示最后添加的对象.我想一次在JFrame上显示两个对象.下面给出的代码只显示了ball1对象.

    JFrame f = new JFrame("Moving"); 
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //making 2 objects 
    Ballbewegung2 ball = new Ballbewegung2();
    Ballbewegung3 ball1 = new Ballbewegung3(); 
    JPanel contentPane = new JPanel(new BorderLayout());
    JPanel contentPane1 = new JPanel(new BorderLayout());

    //adding objects to JPanel
    contentPane.add(ball, BorderLayout.CENTER);                 
    contentPane1.add(ball1, BorderLayout.CENTER);                 

    //Adding JPanel to JFrmae
    f.getContentPane().add(contentPane);
    f.getContentPane().add(contentPane1);
    f.setSize(500, 500);
    f.setVisible(true);