A main JFrame with a button to open a new JDialog - MVC

[Besjamain Greenaway]

Somebody suggested to look how the JOptionPane is implemented, but I couldn't find anything. What I want is seemingly very simple: I have a main JFrame with a button on it. When that button is clicked, I want a new screen to come up. This main JFrame is having its behaviour separated out into another class (sort of a controller). The screen that comes up when the button on the main JFrame is clicked uses MVC. My question is this: The new screen and the controller for that screen needs to be created somewhere. I know it doesn't go in the view of the main JFrame, but having it in a method in the controller doesn't seem right as well.

What is a right solution?

[pete stein]

Besjamain Greenaway wrote:but having it in a method in the controller doesn't seem right as well.

Why not? It seems fine to me.

[Besjamain Greenaway]

As far as I think I know, the controller is the class that delegates actions to the model and enables/disables buttons in the view when necessary. It doesn't seem the place for object creation/creating new views. With emphasis on seem, because I have no clue as to how it really is

[pete stein]

You can still have the JDialog creation code all in a separate GUI/view class and just instantiate that via the controller. While the controller shouldn't hold GUI code, it certainly is going to have to interact with the GUI classes.

[Besjamain Greenaway]

Well, today I started churning out some code for this:

Code for the first window you see, the Main window:

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

public class MainView implements ActionListener
{
  private IMainController mainController;
  private JButton bKlanten;
  private JButton bMenus;
  private JButton bTafels;
  private JButton bReserveringen;
  private JFrame frame;

  public MainView(IMainController mainController)
  {
    this.mainController = mainController;
  }

  public void createMainView()
  {
    frame = new JFrame();
    frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);

    Container contentPane = frame.getContentPane();

    JPanel mainButtonPanel = new JPanel();
    mainButtonPanel.setLayout(new GridLayout(1, 4));

    JList list = new JList();

    bKlanten = new JButton("Klanten");
    bMenus = new JButton("Menu's");
    bTafels = new JButton("Tafels");
    bReserveringen = new JButton("Reserveringen");
    bKlanten.addActionListener(this);
    bMenus.addActionListener(this);
    bTafels.addActionListener(this);
    bReserveringen.addActionListener(this);

    mainButtonPanel.add(bKlanten);
    mainButtonPanel.add(bMenus);
    mainButtonPanel.add(bTafels);
    mainButtonPanel.add(bReserveringen);

    frame.getContentPane().add(mainButtonPanel, BorderLayout.SOUTH);
    frame.setSize(500, 500);

    Dimension frameSize = frame.getSize();
    Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
    frame.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);

    frame.setVisible(true);
  }

  public JFrame getFrame()
  {
    return this.frame;
  }

  public void actionPerformed(ActionEvent event)
  {
    if (event.getSource() == bKlanten)
    {
      System.out.println("Main - Klanten");
    }
    else if (event.getSource() == bMenus)
    {
      System.out.println("Main - Menu's");
    }
   else if (event.getSource() == bTafels)
    {
      mainController.createTafelView();
    }
    else if (event.getSource() == bReserveringen)
    {
      System.out.println("Main - Reserveringen");
    }
  }
}

the controller for the Main window:

public class MainController implements IMainController
{
  private MainView mainView;

  public MainController()
  {
    this.mainView = new MainView(this);
    mainView.createMainView();
  }

  public void createTafelView()
  {
    TafelController tc = new TafelController(mainView.getFrame());
  }
}

Code for the second window:

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

public class TafelView implements ActionListener
{
  private JList list;
  private ITafelController tafelController;
  private JButton bInvoeren;
  private JButton bWijzigen;
  private JButton bVerwijderen;
  private JButton bAnnuleren;
  private JDialog muteerDialog;

  public TafelView(ITafelController tafelController)
  {
    this.tafelController = tafelController;
  }

  public void createTafelView(JFrame parent)
  {
    muteerDialog = new JDialog(parent, "Muteren tafel", true);
    //muteerDialog.setDefaultCloseOperation(muteerDialog.EXIT_ON_CLOSE);

    JPanel p1 = new JPanel();
    p1.setLayout(new GridLayout(1, 4));

    Student[] v = new Student[3];
    v[0] = new Student("1234", "Kees Jansma");
    v[1] = new Student("5678", "Friet Mann");
    v[2] = new Student("9876", "Piet Breed");

    final JList list = new JList(v);
    list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

    bInvoeren = new JButton("Invoeren");
    bWijzigen = new JButton("Wijzigen");
    bVerwijderen = new JButton("Verwijderen");
    bAnnuleren = new JButton("Annuleren");
    bInvoeren.addActionListener(this);
    bWijzigen.addActionListener(this);
    bVerwijderen.addActionListener(this);
    bAnnuleren.addActionListener(this);

    p1.add(bInvoeren);
    p1.add(bWijzigen);
    p1.add(bVerwijderen);
    p1.add(bAnnuleren);

    Container contentPane = muteerDialog.getContentPane();
    contentPane.add(list);
    contentPane.add(p1, BorderLayout.SOUTH);

    muteerDialog.setSize(450, 400);
    muteerDialog.setVisible(true);
  }

  public void enableWijzigenKnop()
  {
    bWijzigen.setEnabled(true);
  }

  public void disableWijzigenKnop()
  {
    bWijzigen.setEnabled(false);
  }

  public void enableVerwijderenKnop()
  {
    bVerwijderen.setEnabled(true);
  }

  public void disableVerwijderenKnop()
  {
    bVerwijderen.setEnabled(false);
  }

  public void actionPerformed(ActionEvent event)
  {
    if (event.getSource() == bInvoeren)
    {
      tafelController.Invoeren();
    }
    else if (event.getSource() == bWijzigen)
    {
      tafelController.Wijzigen();
    }
    else if (event.getSource() == bVerwijderen)
    {
      tafelController.Verwijderen();
    }
    else if (event.getSource() == bAnnuleren)
    {
      muteerDialog.setVisible(false);
      muteerDialog.dispose();
    }
  }

  public String toString()
  {
    return "Ik besta - TafelView!";
  }
}

Code for the controller of the second window:

import javax.swing.*;

public class TafelController implements ITafelController
{
  private TafelView tafelView;

  public TafelController(JFrame parentFrame)
  {
    tafelView = new TafelView(this);
    tafelView.createTafelView(parentFrame);
    tafelView.disableWijzigenKnop();
    tafelView.disableVerwijderenKnop();
  }

  public void Invoeren()
  {
    System.out.println("Invoeren");
  }

  public void Wijzigen()
  {
    System.out.println("Wijzigen");
  }

  public void Verwijderen()
  {
    System.out.println("verwijderen");
  }

  public String toString()
  {
    return "TafelController, present!";
  }
}

So, is this code any good? Is it how it's supposed to? There are still some bugs that need to be fixed - In the constructor it only runs till the second line:

  public TafelController(JFrame parentFrame)
  {
    tafelView = new TafelView(this);
    tafelView.createTafelView(parentFrame);
    tafelView.disableWijzigenKnop(); <-------------------- This doesn't go :(
    tafelView.disableVerwijderenKnop(); <-------------------- This doesn't go :(
  }

[pete stein]

It's hard to judge this out of context. Could you create a Jar file of your current program so we can inspect and run it? If it can't be posted here, then there are other places it can be posted, and then post a link.

[Michael Dunn]

> Somebody suggested to look how the JOptionPane is implemented,

how it is used

let's say your frame has a button, when clicked it does something via the controller.
if something is not right (invalid data?) a warning message might pop up

JOptionPane.showMessageDialog(null,"Warning");
that's using a static method, but it could also be done the normal way = new ....

JOptionPane opt = new JOptionPane();
opt.showMessageDialog(null,"Warning");

now, where is the code, it's not in your controller, instead it's being used/called by your controller.
the code is in a class, in a package, imported.

[Besjamain Greenaway]

Ok, I jarred my files, put I'm not allowed to upload them here... See if this works:

JAR with GUI for multiple frames

[Besjamain Greenaway]

Did you manage to download the files? I couldn't upload any JAR's or ZIP's here on the forum...