java - Java 中的按钮和 JLabel

Question

我正在尝试编写一个 Java 程序，当您单击按钮时，它会隐藏按钮并显示图像。我已经做到了，按钮消失了，但标签没有出现。这是我的代码：

final JLabel label = new JLabel(image, JLabel.CENTER);
label.setAlignmentX(0);
label.setAlignmentY(0);
label.setVisible(false);
label.setIcon(image);

final JButton button = new JButton("CLICK");
button.addActionListener(new ActionListener(){

    @Override
    public void actionPerformed(ActionEvent e) {
        button.setVisible(false);
        label.setVisible(true);
    }

});

Answer 1

解决方案是将按钮和标签放在同一个面板上。最初隐藏标签。然后，当单击按钮时，隐藏按钮并取消隐藏标签。

这是一个例子：

public class MagicButton {

    public static void main(String[] args) {
        // Components
        final JFrame frame = new JFrame("Magic Button");
        final JButton btn = new JButton("Now, you see me!");
        final JLabel label = new JLabel("Now, you don't!");

        // Arrangement
        frame.setLayout(new FlowLayout(FlowLayout.CENTER, 10, 10));
        frame.add(label);
        frame.add(btn);

        // Make Label invisible
        label.setVisible(false);

        // When button clicked: hide button, show label, repack frame
        btn.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                btn.setVisible(false);
                label.setVisible(true);
                frame.pack();
            }
        });

        // pack and display
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

Answer 2

将所有项目放在 a 上JFrame并在 arevalidate()上执行JFrame以显示更改。

Answer 3

试试这个...

public class NewJFrame extends javax.swing.JFrame {

    /**
     * Creates new form NewJFrame
     */
    public NewJFrame() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        jButton1 = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jButton1.setText("jButton1");
        jButton1.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
                jButton1MouseClicked(evt);
            }
        });

        jLabel1.setIcon(new javax.swing.ImageIcon(getClass().getResource("/images/1371634490.png"))); // NOI18N
        jLabel1.setText("jLabel1");
        jLabel1.setVisible(false);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton1)
                .addGap(159, 159, 159))
            .addGroup(layout.createSequentialGroup()
                .addGap(148, 148, 148)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 132, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(120, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addGap(48, 48, 48)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 104, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 34, Short.MAX_VALUE)
                .addComponent(jButton1)
                .addGap(91, 91, 91))
        );

        pack();
    }// </editor-fold>

    private void jButton1MouseClicked(java.awt.event.MouseEvent evt) {
        // TODO add your handling code here:

        jLabel1.setVisible(true);
        jButton1.setVisible(false);
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /*
         * Set the Nimbus look and feel
         */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /*
         * If Nimbus (introduced in Java SE 6) is not available, stay with the
         * default look and feel. For details see
         * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /*
         * Create and display the form
         */
        java.awt.EventQueue.invokeLater(new Runnable() {

            public void run() {
                new NewJFrame().setVisible(true);
            }
        });
    }
    // Variables declaration - do not modify
    private javax.swing.JButton jButton1;
    private javax.swing.JLabel jLabel1;
    // End of variables declaration
}