Java / Scala Swing：使组件连续填充所有可用空间

Question

我尝试使用GridBagLayout创建一个使用Swing的布局。

我想放置一个除了Button之外的ComboBox，其中Button的大小是常量，ComboBox填充该行中的所有可用空间：

但是，如果我放大窗口，ComboBox和Button之间会出现空白区域：

如何布置此表单，以便ComboBox填充所有空间，即使调整窗口大小？

Scala中组件的布局代码：

layout(button) = new Constraints() {
    gridx = 1
    gridy = 0
    anchor = GridBagPanel.Anchor.LineEnd
}

layout(comboBox) = new Constraints() {
    gridx = 0
    gridy = 0
    fill = GridBagPanel.Fill.Horizontal
}

layout(centerPanel) = new Constraints() {
    gridx = 0
    gridy = 1
    weighty = 1
    weightx = 1
    gridwidth = 2
    fill = GridBagPanel.Fill.Both
}

Answer 1

对GUI的该部分使用BorderLayout。把组合。在CENTER和LINE_END中的按钮。

像这样：

import java.awt.BorderLayout;
import javax.swing.*;
import javax.swing.border.*;

public class StretchComboLayout {

    public static void main(String[] args) {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                JPanel ui = new JPanel(new BorderLayout(2, 2));
                ui.setBorder(new EmptyBorder(4, 4, 4, 4));

                JPanel controls = new JPanel(new BorderLayout(2, 2));
                ui.add(controls, BorderLayout.PAGE_START);
                String s = new String(Character.toChars(8594));
                String[] items = {"Choice: right " + s + " arrow"};
                JComboBox cb = new JComboBox(items);
                controls.add(cb, BorderLayout.CENTER);
                controls.add(new JButton("Button"), BorderLayout.LINE_END);

                JSplitPane sp = new JSplitPane(
                        JSplitPane.VERTICAL_SPLIT, 
                        new JTextArea(4,40), 
                        new JTextArea(4,40));

                ui.add(sp, BorderLayout.CENTER);

                JFrame f = new JFrame("Stretch Combo Layout");
                f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
                f.setContentPane(ui);
                f.pack();
                f.setLocationByPlatform(true);
                f.setVisible(true);
            }
        };
        SwingUtilities.invokeLater(r);
    }
}