Question

我有一个使用BorderLayout的中大型UI;该中心是一个标签式窗格，包含各种布局等各种面板。

我希望此边框布局中心的面板根据大小调整大小窗口，但我不希望面板内的组件伸展。标签，组合框，文本字段，按钮 - 我希望它们保持其首选尺寸，并允许包含它们的面板拉伸。我将它们放在滚动窗格中，以防空间对于面板来说太小。

各种海报与丰富多彩的词汇表警告在组件上使用任何setXXXsize（）方法的危险。这就是我现在所做的，而且我想学习如何避免它。

GridBagLayout不适合我的某些面板。它本质上是围绕行和列定向的，并不是所有东西都适合行和列。当然，我可以创建人工行和列以适应所有内容，但我真的希望Swing有更多的布局选项。

垂直胶水也不能。我把它包含在HFOE心爱的SSCE中：

    package example;

    import java.awt.BorderLayout;

    import javax.swing.Box;
    import javax.swing.BoxLayout;
    import javax.swing.JComboBox;
    import javax.swing.JFrame;
    import javax.swing.JLabel;
    import javax.swing.JPanel;

    public class BorderAndBox extends JFrame
    {
        public static void main(String args[])
        {
            BorderAndBox bnb = new BorderAndBox();
            bnb.createUI();
            bnb.setVisible(true);
        }

        public void createUI()
        {
            JPanel borderPanel = new JPanel(new BorderLayout());

            JLabel northLabel = new JLabel("Nawth");
            borderPanel.add(northLabel, BorderLayout.NORTH);

            String[] southComboChoices = { "one", "two", "three" };
            JComboBox southCombo = new JComboBox(southComboChoices);
            borderPanel.add(southCombo, BorderLayout.SOUTH);

            JPanel centerPanel = new JPanel();
            centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.PAGE_AXIS));
            String[] firstChoices = { "first", "uno", "UN" };
            String[] secondChoices = { "second", "dos", "zwei" };
            String[] thirdChoices = { "third", "tres", "drei" };
            JComboBox firstCombo = new JComboBox(firstChoices);
            JComboBox secondCombo = new JComboBox(secondChoices);
            JComboBox thirdCombo = new JComboBox(thirdChoices);
            centerPanel.add(firstCombo);
            centerPanel.add(secondCombo);
            centerPanel.add(thirdCombo);
            centerPanel.add(Box.createVerticalGlue());  // first attempt; does NOT
            // take up available vertical space, instead it appears to create a space
            // that is shared equally among the (now) four components of this space.
            borderPanel.add(centerPanel, BorderLayout.CENTER);

            getContentPane().add(borderPanel);
            pack();
        }

    }

如果放大窗口，中间的组合框会放大;如上所述，它们下方的垂直胶片也会扩大，但不会占用所有可用空间。似乎给它们提供了与每个空间一样多的空间。

那么解决这个问题的好方法是什么？

Answer 1

BorderAndBox - centered

import java.awt.BorderLayout;
import java.awt.GridBagLayout;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class BorderAndBox extends JFrame
{
public static void main(String args[])
{
    BorderAndBox bnb = new BorderAndBox();
    bnb.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
    bnb.createUI();
    bnb.setVisible(true);
}

public void createUI()
{
    JPanel borderPanel = new JPanel(new BorderLayout());

    JLabel northLabel = new JLabel("Nawth");
    borderPanel.add(northLabel, BorderLayout.NORTH);

    String[] southComboChoices = { "one", "two", "three" };
    JComboBox southCombo = new JComboBox(southComboChoices);
    borderPanel.add(southCombo, BorderLayout.SOUTH);

    JPanel centerPanel = new JPanel();
    centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.PAGE_AXIS));
    String[] firstChoices = { "first", "uno", "UN" };
    String[] secondChoices = { "second", "dos", "zwei" };
    String[] thirdChoices = { "third", "tres", "drei" };
    JComboBox firstCombo = new JComboBox(firstChoices);
    JComboBox secondCombo = new JComboBox(secondChoices);
    JComboBox thirdCombo = new JComboBox(thirdChoices);
    centerPanel.add(firstCombo);
    centerPanel.add(secondCombo);
    centerPanel.add(thirdCombo);
    centerPanel.add(Box.createVerticalGlue());  // first attempt; does NOT
    // take up available vertical space, instead it appears to create a space
    // that is shared equally among the (now) four components of this space.
    JPanel centerPanelConstrain = new JPanel(new GridBagLayout());
    centerPanelConstrain.add(centerPanel);
    borderPanel.add(centerPanelConstrain, BorderLayout.CENTER);

    getContentPane().add(borderPanel);
    pack();
}

}

另见this answer。解决这个问题的方法不止一种。

Answer 2

我建议您将JPanel与javax.swing.GroupLayout一起使用。但是通过编码来使用这种布局并不容易。使用Netbeans Matisse Builder之类的代码生成器，如果您不想使用IDE，请将其粘贴到您想要的任何位置。

将首选组件的大小保持在BorderLayout的中心

2 个答案: