java - 使 BoxLayout 将组件移动到顶部，同时从左到右堆叠

Question

我有一个 JPanel，它在 X_AXIS 方向上使用了一个 BoxLayout。我遇到的问题最好用一张图片展示:

如您所见，左侧的 JPanel 已居中而不是顶部对齐。我希望它们都在顶部对齐并从左到右堆叠，如何使用此布局管理器实现此目的？我写的代码如下:

public GameSelectionPanel(){

    setLayout(new BoxLayout(this, BoxLayout.X_AXIS));

    setAlignmentY(TOP_ALIGNMENT);

    setBorder(BorderFactory.createLineBorder(Color.black));

    JPanel botSelectionPanel = new JPanel();

    botSelectionPanel.setLayout(new BoxLayout(botSelectionPanel, BoxLayout.Y_AXIS));

    botSelectionPanel.setBorder(BorderFactory.createLineBorder(Color.red));

    JLabel command = new JLabel("Please select your opponent:"); 

    ButtonGroup group = new ButtonGroup();

    JRadioButton button1 = new JRadioButton("hello world");
    JRadioButton button2 = new JRadioButton("hello world");
    JRadioButton button3 = new JRadioButton("hello world");
    JRadioButton button4 = new JRadioButton("hello world");

    group.add(button1);
    group.add(button2);
    group.add(button3);
    group.add(button4);

    botSelectionPanel.add(command);
    botSelectionPanel.add(button1);
    botSelectionPanel.add(button2);
    botSelectionPanel.add(button3);
    botSelectionPanel.add(button4);

    JPanel blindSelectionPanel = new JPanel();
    blindSelectionPanel.setBorder(BorderFactory.createLineBorder(Color.yellow));

    blindSelectionPanel.setLayout(new BoxLayout(blindSelectionPanel, BoxLayout.Y_AXIS));

    JRadioButton button5 = new JRadioButton("hello world");
    JRadioButton button6 = new JRadioButton("hello world");

    ButtonGroup group2 = new ButtonGroup();
    group2.add(button5);
    group2.add(button6);

    JLabel blindStructureQuestion = new JLabel("Please select the blind structure:");

    blindSelectionPanel.add(blindStructureQuestion);
    blindSelectionPanel.add(button5);
    blindSelectionPanel.add(button6);

    add(botSelectionPanel);
    add(blindSelectionPanel);

    setVisible(true);
}

Answer 1

Riduidel在 GameSelectionPanel 本身上设置 setAlignmentY 是正确的，GridBagLayout 是一个很好的选择。如果您更喜欢使用 BoxLayout，文章 Fixing Alignment Problems讨论此事，建议“由从左到右的 Boxlayout 控制的所有组件通常应具有相同的 Y 对齐方式。”在您的示例中，添加

botSelectionPanel.setAlignmentY(JPanel.TOP_ALIGNMENT);
blindSelectionPanel.setAlignmentY(JPanel.TOP_ALIGNMENT);