Question

我有一个JLabel，里面会有很多文字，所以我需要添加新行。我发现为了做到这一点，你需要在你的JLabel和<br>中使用html来换行。好吧，只要我将HTML添加到我的JLabel就消失了!!

以下是JLabel的图片，其中包含以下代码：

instructionLabel = new JLabel("lol");
instructionLabel.setBounds(25,10,500,100);
add(instructionLabel);

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现在，当我更改代码时，只要添加html，它就会消失：

instructionLabel = new JLabel("<html>lol</html>");
instructionLabel.setBounds(25,10,500,100);
add(instructionLabel);

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该程序没有错误＆amp;如果有必要，我愿意提供更多代码。

Answer 1

避免使用null布局，像素完美布局是现代ui设计中的一种幻觉。影响组件个体大小的因素太多，您无法控制。 Swing旨在与布局管理器一起工作，放弃这些将导致问题和问题的终结，您将花费越来越多的时间来纠正

here

import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class LabelExample {

    public static void main(String[] args) {
        new LabelExample();
    }

    public LabelExample() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            add(new JLabel("Look ma, no html"));
            add(new JLabel("<html>Look ma, html</html>"));
        }

    }

}

有关详细信息，请参阅

基于此要求...

Laying Out Components Within a Container

我做了一个简单的GridBagLayout并制作了这个......

import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.LineBorder;

public class LabelExample {

    public static void main(String[] args) {
        new LabelExample();
    }

    public LabelExample() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            setLayout(new GridBagLayout());
            JLabel points = new JLabel("<html><b>Points: 0</b></html>");
            JLabel highscore = new JLabel("<html><b>Highscore: 0</b></html>");
            JLabel score = new JLabel("97");
            score.setFont(score.getFont().deriveFont(Font.BOLD, 96));

            GridBagConstraints gbc = new GridBagConstraints();
            gbc.gridx = 0;
            gbc.gridy = 0;
            gbc.weightx = 1;
            add(points, gbc);
            gbc.gridx = 2;
            add(highscore, gbc);

            gbc.weightx = 0;
            gbc.weighty = 1;
            gbc.gridx = 1;
            gbc.anchor = GridBagConstraints.CENTER;
            gbc.gridy++;
            gbc.ipadx = 50;
            gbc.ipady = 50;
            score.setHorizontalAlignment(JLabel.CENTER);
            add(score, gbc);

            JButton high = new JButton("High");
            JButton low = new JButton("Low");

            gbc = new GridBagConstraints();
            gbc.gridx = 0;
            gbc.gridy = 2;
            gbc.fill = GridBagConstraints.HORIZONTAL;
            add(high, gbc);
            gbc.gridx = 2;
            add(low, gbc);
        }


    }

}

这只是一个粗略的开始，提供了一个基本的想法

Answer 2

// You can try below code to solve your problem. 
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.Font;

public class Tutorial extends JFrame {

    public static void main(String[] args) {
     new Tutorial();
    }

    public Tutorial() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 450, 300);
        getContentPane().setLayout(null);

        JLabel instructionLabel = new JLabel("<html><p>lol <br> Working</p></html>");
        instructionLabel.setFont(new Font("Tahoma", Font.BOLD, 12));
        instructionLabel.setBounds(25,10,500,100);
        getContentPane().add(instructionLabel);
        setVisible(true);
    }
}

使用html

2 个答案: