如何在 for 循环中添加 JButton？

Question

So I am making an UI in a minecraft plugin, and it adds a button for every player, and when we click the button, it kicks the player. This is the for loop:

for (final Player p : Bukkit.getOnlinePlayers())
    {
        System.out.println("Looping.");
        final JButton b = new JButton();
        b.setName(p.getName());
        b.setText(p.getName());
        b.setToolTipText("Kick " + b.getText());
        b.setBackground(Color.GREEN);
        b.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (!b.getBackground().equals(Color.RED))
                {
                        Bukkit.getScheduler().runTask(main, new Runnable() {
                            public void run() {
                                Bukkit.getPlayer(b.getText()).kickPlayer(jtf.getText());
                            b.setBackground(Color.RED);
                            }
                        });
                }

            }
        });
        System.out.println("Button added.");
        f.add(b);
    }

And let's say there are 2 players in the server, asd and dsa . When this for loop runs, it just adds button for asd , but prints Button added (and Looping ) two times.

( f is a public static JFrame , and jtf is a public static JTextField )

So... Why is it not working?

Answer 1

It happens because the defult LayoutManager is BorderLayout , so the method add(JComponent comp) puts the JComponent in the center of the JFrame , and the JComponent fills the entire JFrame . Use the method f.setLayout(new GridLayout(number_of_players, 1)); , it will split the JFrmae to rows as the number of your players, so a multiply number of JComponents could be displayed.