组件未在我的jpanel上更新

Question

可能重复:
JLabel仅显示是否删除了initComponents()

JavaApplication1.java

这是我打电话给我单独的小组的地方.

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package javaapplication1;

import javax.swing.JFrame;

/**
 *
 * @author Aires
 */
public class JavaApplication1 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
       JFrame f = new JFrame();
       NewJPanel n1 = new NewJPanel();
       f.add(n1);
       f.pack();
       f.show();
    }
}

newJPanel.java即时创建新的JLabel以添加到我当前的面板中,但是当我运行该程序时,它没有显示出来.

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

/*
 * NewJPanel.java
 *
 * Created on Nov 10, 2012, 3:07:31 PM
 */
package javaapplication1;

import javax.swing.JLabel;


/**
 *
 * @author Aires
 */
public class NewJPanel extends javax.swing.JPanel {

    /** Creates new form NewJPanel */
    public NewJPanel() {
        //pag kinoment ko ito, tsaka lang lamalabas yung jlabel.
        initComponents();

        //dito Sir, di siya nalalagay sa panel.
        JLabel n = new JLabel();
        n.setText("asdasdasd");
        this.add(n);
    }


    /** 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() {

        jLabel1 = new javax.swing.JLabel();

        jLabel1.setText("jLabel1");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(175, 175, 175)
                .addComponent(jLabel1)
                .addContainerGap(191, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(127, 127, 127)
                .addComponent(jLabel1)
                .addContainerGap(159, Short.MAX_VALUE))
        );
    }// </editor-fold>
    // Variables declaration - do not modify
    private javax.swing.JLabel jLabel1;
    // End of variables declaration
}

我编写创建的JLabel没有显示,它只显示我注释掉// initComponents(); 对此有何解决方案？

Answer 1

• JLabel n = new JLabel(); 是不可见的,因为使用了GroupLayout所需的一堆代码vertical和horizontal坐标JPanel

• JLabel n = new JLabel();缺少这些用于jLabel1 = new javax.swing.JLabel();进入的坐标private void initComponents() {然后JLabel n = new JLabel();无法看到JPanel,你只能看到jLabel1

• 删除代码块private void initComponents() {并继续手动编写GUI

• JPanel已FlowLayout在API中实现

• JFrame已BorderLayout在API中实现

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class JavaApplication1 {

    private JFrame frame = new JFrame();
    private JPanel panel = new JPanel();
    private JLabel label = new JLabel();

    public JavaApplication1() {
        label.setText("asdasdasd");
        panel.add(label);
        frame.add(panel);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                JavaApplication1 j1 = new JavaApplication1();
            }
        });
    }
}