java - 将4个JLabel放在JFrame的角落

就像标题所说的那样，我试图在JFrame的每个角上放置4个不同的JLabel。我希望他们永远呆在那里，即使我尝试调整JFrame的大小

我已经尝试过使用布局管理器，但是我做对了。

    ImageIcon icon;
    JLabel labelNW = new JLabel();
    JLabel labelNE = new JLabel();
    JLabel labelSW = new JLabel();
    JLabel labelSE = new JLabel();
    URL buttonURL = InputOutputTest.class.getResource("images/square_dot.gif");
    if(buttonURL != null){
        icon = new ImageIcon(buttonURL);
        labelNW.setIcon(icon);
        labelNE.setIcon(icon);
        labelSW.setIcon(icon);
        labelSE.setIcon(icon);
    }
    window.add(labelNW, BorderLayout.NORTH);
    //window.add(labelNE, BorderLayout.EAST);
    //window.add(labelSW, BorderLayout.WEST);
    window.add(labelSE, BorderLayout.SOUTH);

该代码负责左侧的北部和南部。我可能正在解决这个错误。

我也尝试了GridLayout(2,2)，但是它们不在角落，右侧有很大的空隙。

最佳答案

您将需要使用各自的布局来嵌套JPanels。实际上，您可以通过嵌套全部使用BorderLayout的JPanels来做到这一点。

要检查GridBagLayout是否可以一击就完成....挂起...

是的GridBagLayout也这样做:

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;

import javax.swing.*;

public class GridBagExample {
   public static void main(String[] args) {
      JPanel mainPanel = new JPanel(new GridBagLayout());

      GridBagConstraints gbc = new GridBagConstraints(0, 0, 1, 1, 1.0, 1.0,
            GridBagConstraints.NORTHWEST, GridBagConstraints.NONE, new Insets(
                  0, 0, 0, 0), 0, 0);
      mainPanel.add(new JLabel("Left Upper"), gbc);

      gbc.gridx = 1;
      gbc.gridy = 0;
      gbc.anchor = GridBagConstraints.NORTHEAST;
      mainPanel.add(new JLabel("Right Upper"), gbc);

      gbc.gridx = 0;
      gbc.gridy = 1;
      gbc.anchor = GridBagConstraints.SOUTHWEST;
      mainPanel.add(new JLabel("Left Lower"), gbc);

      gbc.gridx = 1;
      gbc.gridy = 1;
      gbc.anchor = GridBagConstraints.SOUTHEAST;
      mainPanel.add(new JLabel("Right Lower"), gbc);

      JFrame frame = new JFrame("Test");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.setLocationRelativeTo(null);
      frame.pack();
      frame.setVisible(true);
   }
}

编辑
现在以BorderLayout为例:

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

import javax.swing.*;

public class BorderLayoutExample {
   public static void main(String[] args) {
      JPanel northPanel = new JPanel(new BorderLayout());
      northPanel.add(new JLabel("North East"), BorderLayout.EAST);
      northPanel.add(new JLabel("North West"), BorderLayout.WEST);

      JPanel southPanel = new JPanel(new BorderLayout());
      southPanel.add(new JLabel("South East"), BorderLayout.EAST);
      southPanel.add(new JLabel("South West"), BorderLayout.WEST);


      JPanel mainPanel = new JPanel(new BorderLayout());
      mainPanel.add(northPanel, BorderLayout.NORTH);
      mainPanel.add(southPanel, BorderLayout.SOUTH);

      JFrame frame = new JFrame("BorderLayout Test");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }
}