Adding a panel from a method to a frame

Question

I didn't really know how else to phrase that but essentially:

-I have a few separate "pieces" that I am trying to add onto a master frame; to keep the code from getting unwieldy I have each "piece" be its own class.

-I'm getting stuck on adding the panells onto the master frame, because the classes themselves aren't panels, rather the method of the class creates the panel, which creates issues that I don't know how to solve.

PIECE (works on its own when I have it make a dialog instead of be a panel):

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


public class PieceThing3 extends JPanel //<switched from JDialog
{
    //set up variables here


private ActionListener pieceAction = new ActionListener()
{
    public void actionPerformed (ActionEvent ae)
    {
        // Action Listener (this also works)
    }
};

private void createPiece()
{
    //setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
    //setLocationByPlatform(true);
    // the above are commented out when I switch from dialog to panel

    JPanel contentPane = new JPanel();

    //something that uses pieceAction is here

    //two buttons, b and s, with action listeners are here

    contentPane.add(b);
    contentPane.add(s);
    add(contentPane);
    //pack();
       //again, commented out to switch from dialog
    setVisible(true);
    System.out.println("hi I'm done");
      //just to check and make sure it's done
}

public static void main(String[] args) 
{
    // TODO Auto-generated method stub
    SwingUtilities.invokeLater(new Runnable()
    {
        public void run()
        {
            new PieceThing3().createPiece();
        }
    });
}
}

Sorry that is very vague, but the intricacies are not as important as the general idea - it works perfectly when I have it create its own dialog box, but now I am trying to get it to make a panel within a master code, below:

MASTER:

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

public class CollectGUI extends JFrame{


private void createDialog(){
    this.setSize(2000,1000);
    this.setLocation(0,0);
    this.setTitle("TITLE");


    PieceThing3 pt = new PieceThing3();
    //HERE, if I do pt.main(null); while it is in "dialog mode" (rather than panel) it pops up a dialog box and everything is hunky dory. But I don't know how to get it to add the method as a panel.

   this.add(pt.main(null));
   //this gives an error

   this.setVisible(true);
}


public static void main(String[] args) {
    // TODO Auto-generated method stub
    new CollectGUI().createDialog();
}

}

As I said in the comments, if I just do pt.main(null) when pt is set to make a dialog, it does it, but if I try to add pt.main(null) as a panel it throws an error. Can anybody give me some insight on how to add a method of a class rather than a class? I'm pretty stumped.

THANK YOU!!

Answer 1

You are definitely on the right track working to maintain separation of concerns and implement your gui in a number of distinct components. Try something like this:

Panel1

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

public class Panel1 extends JPanel {

    public Panel1() {
        this.add(new JLabel("This is panel 1"));
    }

}

Panel2

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

public class Panel2 extends JPanel {

    public Panel2() {
        this.add(new JLabel("This is panel 2"));
    }

}

JFrame

import java.awt.BorderLayout;

import javax.swing.JFrame;

import org.yaorma.example.jframe.panel.panel1.Panel1;
import org.yaorma.example.jframe.panel.panel2.Panel2;

public class ExampleJFrame extends JFrame {

    public ExampleJFrame() {
        super("Example JFrame Application");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setSize(400,400);
        this.setLayout(new BorderLayout());
        Panel1 pan1 = new Panel1();
        Panel2 pan2 = new Panel2();
        this.add(pan1, BorderLayout.NORTH);
        this.add(pan2, BorderLayout.SOUTH);
        this.setVisible(true);
    }
}

main:

public class ExampleApplication {

    public static void main(String[] args) throws Exception {
        new ExampleJFrame();
    }

}

EDIT: Here's a Panel1 with a little more content.

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

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

import org.yaorma.example.action.sayhello.SayHelloAction;

public class Panel1 extends JPanel {

    //
    // instance variables
    //

    private JButton pressMeButton;

    //
    // constructor
    //

    public Panel1() {
        this.setLayout(new BorderLayout());
        this.add(new JLabel("This is panel 1"), BorderLayout.NORTH);
        this.initPressMeButton();
    }

    //
    // button
    //

    private void initPressMeButton() {
        this.pressMeButton = new JButton("Press Me");
        this.pressMeButton.addActionListener(new PressMeButtonActionListener());
        this.add(pressMeButton, BorderLayout.SOUTH);
    }

    //
    // method to get the parent jframe
    //

    private JFrame getParentJFrame() {
        Container con = this;
        while(con != null) {
            con = con.getParent();
            if(con instanceof JFrame) {
                return (JFrame)con;
            }
        }
        return null;
    }

    //
    // action listener for Press Me button
    //

    private class PressMeButtonActionListener implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            JFrame jFrame = getParentJFrame();
            SayHelloAction action = new SayHelloAction(jFrame);
            action.execute();
        }

    }

}

Action called by button:

import javax.swing.JFrame;
import javax.swing.JOptionPane;

public class SayHelloAction {

    private JFrame owner;

    public SayHelloAction(JFrame owner) {
        this.owner = owner;
    }

    public void execute() {
        JOptionPane.showMessageDialog(owner, "Hello World");
    }

}