Add Jpanel to Jframe NetBeans

问题:

Hi all, I was in a development of my college mini project. It was a Library Management system , which i should do in Java swing using Net-beans IDE. First I was doing manual coding. It takes time.

In manual coding I create single JFrame with Menu bar and and items, on all action performed I wrote codes for all Jpanels. It made the file and code huge. and confusing too.

Now I need your help. I have created a Main JFrame with Menu A JPanel - ADD Book another Jpanel - On add book success (demo! , for Actions happening in ADD Book )

I had made action listener

addBook addbk = new addBook();
this.getContentPane().add(addbk);

wrote this code. I doesn't make sense. Friends, As a new to java, What i need to study is

1.) How cal and Show an external Jpanel an action performed 2.) How to show another JPanel to same root JFrame if any event has occurred in external JPanel.

In sort, something like Iframe in HTML Thank you all.

http://compilr.com/abelkbil/openlib/OpenLibMainGUI.java

http://compilr.com/abelkbil/openlib/addBook.java

http://compilr.com/abelkbil/openlib/bookAdded.java

回答1:

CardLayout, is exactly what you need for this situation. And do learn Java Naming Conventions and stick to them, as you are a beginner, so to be on the right track from the start is always GOOD.

Here is one example, that you can look at :

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class CardLayoutExample
{
    private JPanel contentPane;
    private MyPanel panel1;
    private MyPanel panel2;
    private MyPanel panel3;
    private JComboBox choiceBox;
    private String[] choices = {
                                "Panel 1",
                                "Panel 2",
                                "Panel 3"
                               };

    private void displayGUI()
    {
        JFrame frame = new JFrame("Card Layout Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel contentPane = new JPanel();
        contentPane.setBorder(
            BorderFactory.createEmptyBorder(5, 5, 5, 5));
        contentPane.setLayout(new CardLayout());

        choiceBox = new JComboBox(choices);        

        panel1 = new MyPanel(contentPane
                , Color.RED.darker().darker(), this);
        panel2 = new MyPanel(contentPane
                , Color.GREEN.darker().darker(), this);
        panel3 = new MyPanel(contentPane
                , Color.DARK_GRAY, this);   

        contentPane.add(panel1, "Panel 1"); 
        contentPane.add(panel2, "Panel 2");
        contentPane.add(panel3, "Panel 3");         

        frame.getContentPane().add(choiceBox, BorderLayout.PAGE_START);
        frame.getContentPane().add(contentPane, BorderLayout.CENTER);       
        frame.pack();   
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public JComboBox getChoiceBox()
    {
        return choiceBox;
    }

    public static void main(String... args)
    {
        SwingUtilities.invokeLater(new Runnable()
        {
            public void run()
            {
                new CardLayoutExample().displayGUI();
            }
        });
    }
}

class MyPanel extends JPanel 
{

    private JButton jcomp1;
    private JPanel contentPane;
    private Color backgroundColour;
    private JComboBox choiceBox;

    public MyPanel(JPanel panel, Color c, CardLayoutExample cle) 
    {   
        contentPane = panel;
        backgroundColour = c;
        choiceBox = cle.getChoiceBox();

        setOpaque(true);
        setBackground(backgroundColour);

        //construct components
        jcomp1 = new JButton ("Show New Panel");
        jcomp1.addActionListener( new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                String changeToPanel = (String) choiceBox.getSelectedItem();
                CardLayout cardLayout = (CardLayout) contentPane.getLayout();
                cardLayout.show(contentPane, changeToPanel);
            }
        });

        add(jcomp1);
    }

    @Override
    public Dimension getPreferredSize()
    {
        return (new Dimension(500, 500));
    }
}

Else you can have a look at this example also.