关于java：在BorderLayout的中心保持组件的首选大小

Keeping preferred sizes of components in center of BorderLayout

我有一个使用BorderLayout的中型UI；中心是一个选项卡式窗格，其中包含具有不同布局等的各种面板。

我希望此边框布局中心的面板根据
窗口，但我不希望面板中的组件伸展。标签，组合框，文本字段，按钮-我希望它们保持其首选大小，并允许包含它们的面板伸展。我将它们放在滚动窗格中，以防面板的空间过小。

各种带有丰富词汇的海报警告不要在组件上使用任何setXXXsize()方法的危险。这就是我现在要做的，并且我想学习如何避免它。

GridBagLayout不适合我的某些面板。从本质上讲，它是围绕行和列定向的，并非所有内容都适合行和列。当然，我可以创建人造的行和列以适合所有内容，但是我真的希望Swing具有更多的布局选项。

立式胶水也不做。我已将其包含在HFOE最受欢迎的SSCE中：

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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，则中间的组合框会放大；如所写，它们下面的垂直胶水也会增大，但不会占用所有可用空间。似乎给它们提供了尽可能多的空间。

那么解决这个问题的好方法是什么？

相关讨论

BorderAndBox - centered

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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();
}

}

另请参阅此答案。解决此问题的方法不止一种。