java GUI布局建议

Question

public class AFS {
    public JPanel afs(final Fields input){
        JPanel titlePanel = new JPanel();

        //Title fields
        JLabel afs = new JLabel("Statement", Label.LEFT);

        Label mm = new Label("month ", Label.LEFT);
        Label my = new Label("Year ", Label.LEFT);

        //first line
        titlePanel.add(afs);
        titlePanel.add(mm);
        titlePanel.add(input.MENTRY);
        titlePanel.add(my);
        titlePanel.add(input.YENTRY);
        titlePanel.setPreferredSize(null);

        //Left Panels
        JPanel sb = new JPanel();
        JPanel entry = new JPanel();
        entry.setLayout(new BoxLayout(entry, BoxLayout.Y_AXIS));
        entry.setAlignmentX(Component.LEFT_ALIGNMENT);
        entry.add(new Label("Service "));
        entry.add(input.s);
        entry.add(new Label("Amount "));
        entry.add(input.a);
        entry.add(new Label("Counter "));
        entry.add(input.o);
        entry.add(new Label("Division "));
        entry.add(input.d);

        sb.add(entry);


        JPanel holderPanel = new JPanel();
        holderPanel.setLayout(new BoxLayout(holderPanel, BoxLayout.Y_AXIS));
        holderPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
        holderPanel.add(titlePanel);
        holderPanel.add(sb);

        JButton start = new JButton("Save Current");
        start.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                ScriptAction action = new ScriptAction();
                action.saveAll(input,1);
            }
        });
        holderPanel.add(start); 
        return holderPanel;
    }

我有一个类似于上面代码的简短版本。当前的布局如下所示:

但我希望布局看起来像(已编辑油漆)。

我尝试使用 gridLayout 进行交换，它将显示 2 行，但 gridlayout 仍会将所有内容对齐在中心(包括标题和页眉)。此外，按钮跨度将横跨整个底部。我想知道是否有任何建议的方法可以做到这一点？

Answer 1

您需要使用 layout managers 的组合达到所需的输出:

调整大小之前/调整大小之后

在本例中，有 3 个主要部分:

• 顶部 Pane (使用 Box 来对齐左侧的一些文本和右侧的一些文本)
• 中间 Pane (使用 GridBagLayout 来定位组件，如图所示，也许具有适当插入的 GridLayout 也可以工作)
• 底部 Pane (使用默认的 JPanel 布局:FlowLayout)

顶部 Pane 也使用 2 个 JPanel，第一个单独用于标签 Statement，另一个与 FlowLayout 右对齐对于其他 4 个组件，按照 this answer BoxLayout 不尊重我们 JTextField 的首选大小。因此，解决方法是将它们包装在另一个 JPanel 中，然后将该 JPanel 与 Statement 标签一起包装。

中间 Pane 也出现了类似的问题，它需要使用 2 个 JPanel:一个用于包含在另一个更大的 Pane 中的字段，该 Pane 容纳它，并且 JButton 位于底部(保存当前)。我们可以通过添加带有 gridx = 2 的 JButton 和带有 counter 的 gridy = 2 来实现类似的输出和 gridx = 3 和 gridx = 4 上的 division 标签和字段(而不是 2 & 3)，但是然后，我们需要添加 gbc.insets 以将插图添加到具有高值的顶部和底部...这取决于您使用哪一个:)

产生上述输出的代码如下:

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

public class FormSample {
    private JFrame frame;
    private JPanel topRightPane;
    private JPanel centerPane;
    private JPanel centerWithButtonPane;
    private JPanel buttonsPane;

    private JTextField monthField;
    private JTextField yearField;

    private JTextField serviceField;
    private JTextField amountField;
    private JTextField counterField;
    private JTextField divisionField;

    private static final int LEFT_MARGIN = 50; //Increase / Decrease to add extra space between components
    private static final int RIGHT_MARGIN = LEFT_MARGIN;

    //Change insets accordingly to add extra space between components (top, left, bottom, right)
    private static final Insets leftInsets = new Insets(0, LEFT_MARGIN, 0, 0);
    private static final Insets rightInsets = new Insets(0, 0, 0, RIGHT_MARGIN);
    private static final Insets defaultInsets = new Insets(0, 0, 0, 0);

    private JButton saveCurrentButton;
    private JButton saveAllButton;
    private JButton resetButton;

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new FormSample()::createAndShowGui);
    }

    private void createAndShowGui() {
        frame = new JFrame(getClass().getSimpleName());

        monthField = new JTextField(10);
        yearField = new JTextField(10);

        serviceField = new JTextField(10);
        amountField = new JTextField(10);
        counterField = new JTextField(10);
        divisionField = new JTextField(10);

        saveCurrentButton = new JButton("Save Current");
        saveAllButton = new JButton("Save all");
        resetButton = new JButton("Reset");

        buttonsPane = new JPanel();

        topRightPane = new JPanel();
        topRightPane.setLayout(new FlowLayout(FlowLayout.RIGHT));

        topRightPane.add(new JLabel("Month"));
        topRightPane.add(monthField);
        topRightPane.add(new JLabel("Year"));
        topRightPane.add(yearField);

        centerWithButtonPane = new JPanel();
        centerWithButtonPane.setLayout(new BoxLayout(centerWithButtonPane, BoxLayout.PAGE_AXIS));

        Box box = Box.createHorizontalBox();
        box.add(new JLabel("Statement"));
        box.add(Box.createHorizontalGlue());
        box.add(topRightPane);

        centerPane = new JPanel();
        centerPane.setLayout(new GridBagLayout());

        GridBagConstraints gbc = new GridBagConstraints();

        gbc.gridx = 0;
        gbc.gridy = 0;
        gbc.insets = defaultInsets;
        centerPane.add(new JLabel("Service"), gbc);

        gbc.gridx = 1;
        gbc.insets = rightInsets;
        centerPane.add(serviceField, gbc);

        gbc.gridx = 2;
        gbc.insets = leftInsets;
        centerPane.add(new JLabel("Counter"), gbc);

        gbc.gridx = 3;
        gbc.insets = defaultInsets;
        centerPane.add(counterField, gbc);

        gbc.gridx = 0;
        gbc.gridy = 1;
        gbc.insets = defaultInsets;
        centerPane.add(new JLabel("Amount"), gbc);

        gbc.gridx = 1;
        gbc.insets = rightInsets;
        centerPane.add(amountField, gbc);

        gbc.gridx = 2;
        gbc.insets = leftInsets;
        centerPane.add(new JLabel("Division"), gbc);

        gbc.gridx = 3;
        gbc.insets = defaultInsets;
        centerPane.add(divisionField, gbc);

        saveCurrentButton.setAlignmentX(Component.CENTER_ALIGNMENT); //Force centered alignment for our JButton
        centerWithButtonPane.add(centerPane);
        centerWithButtonPane.add(saveCurrentButton);

        buttonsPane.add(saveAllButton);
        buttonsPane.add(resetButton);

        frame.add(box, BorderLayout.NORTH);
        frame.add(centerWithButtonPane, BorderLayout.CENTER);
        frame.add(buttonsPane, BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

另外，请遵循 @SergiyMedvynskyy 给出的关于不要混合使用 AWT 和 Swing 组件(即 JTextField 与 TextField)的建议，并且仅使用 Swing 组件，因为 AWT 组件存在错误。