Java swing 按钮布局尺寸不匹配

Question

我正在尝试制作一个带有按钮和列表的面板，以在其中选择不同的选项。但无论我做什么，我都无法使它们具有相同的大小。

从我的“动画师”类中，我想向东侧的 JFrame 添加一个按钮面板。居中的是一个移动盒子的动画，但尚未创建。我想我先制作按钮面板。

我已经尝试过setPreferedSize(newDimension(x,y))，但如果我在按钮上执行此操作，JComboBox也会改变。和 button 仍然保持不变。我很困惑。

选择另一个选项后Jcombobox也没有任何操作？不应该吗？

这是动画器代码:

frame = new JFrame("Box Mover Calculator!");
    frame.setLayout(new BorderLayout());
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(500, 500);
    frame.setLocationRelativeTo(null);

    buttonArea = new ButtonPanel(this); 
    boxArea = new JPanel(new GridLayout(1,1));
    frame.add(boxArea, BorderLayout.CENTER);
    frame.add(buttonArea, BorderLayout.EAST);
    frame.setVisible(true);

这是按钮面板:

public ButtonPanel(Animator animator) {
    super();
    //this.animator = animator;
    //setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
    buttonRow = new JPanel();
    buttonRow.setLayout(new BoxLayout(buttonRow, BoxLayout.PAGE_AXIS));
    buttonRow.setBackground(Color.CYAN);
    this.setBackground(Color.CYAN);

    button1 = new JButton("Start Animation");
    button1.addActionListener(new QuitHandler());
    button1.setBackground(Color.CYAN);
    button1.setForeground(Color.blue);
    buttonRow.add(button1);

    button2 = new JButton("Move Box");
    button2.addActionListener(new QuitHandler());
    button2.setBackground(Color.CYAN);
    button2.setForeground(Color.blue);
    button2.setOpaque(true);
    buttonRow.add(button2);

    String[] bookTitles = new String[] {"Effective Java", "Head First Java",
            "Thinking in Java", "Java for Dummies"};

    JComboBox<String> bookList = new JComboBox<>(bookTitles);

    //add to the parent container (e.g. a JFrame):
    buttonRow.add(bookList);

    //get the selected item:
    String selectedBook = (String) bookList.getSelectedItem();
    System.out.println("You seleted the book: " + selectedBook);

    //Adds all rows
    add(buttonRow);     
    setVisible(true);

}

这是快照，

Answer 1

例如，也许尝试使用 GridBagLayout...

public class TestPane extends JPanel {

    public TestPane() {
        setLayout(new BorderLayout());
        JPanel buttonRow = new JPanel(new GridBagLayout());
        buttonRow.setBackground(Color.CYAN);
        this.setBackground(Color.CYAN);

        GridBagConstraints gbc = new GridBagConstraints();
        gbc.gridwidth = GridBagConstraints.REMAINDER;
        gbc.fill = GridBagConstraints.HORIZONTAL;

        JButton button1 = new JButton("Start Animation");
        button1.setBackground(Color.CYAN);
        button1.setForeground(Color.blue);
        buttonRow.add(button1, gbc);

        JButton button2 = new JButton("Move Box");
        button2.setBackground(Color.CYAN);
        button2.setForeground(Color.blue);
        button2.setOpaque(true);
        buttonRow.add(button2, gbc);

        String[] bookTitles = new String[]{"Effective Java", "Head First Java",
            "Thinking in Java", "Java for Dummies"};

        JComboBox<String> bookList = new JComboBox<>(bookTitles);

        gbc.weighty = 1;
        gbc.anchor = GridBagConstraints.NORTH;
        //add to the parent container (e.g. a JFrame):
        buttonRow.add(bookList, gbc);

        //Adds all rows
        add(buttonRow);
    }

}

参见How to Use GridBagLayout了解更多详情