ActionPerformed & update(Model,Object) in mvc and GridBagLayout

Question

I have severall question and excuse my denglish! Problems:

My actionPerformed in my controller dont react
and I dont know how to use the update(model,object) method in the View.
The next problem is my GridBag. It looks chaotic although the code is orientated on the oracle example.
No the Last one. in the view line 41 i get a NPE as a result of a class initialised in the Model. dont no why. I allready testes if the Class is constructed and yes it is.

The Programm should greate a JuliaSet. Classes without theire imports Controller:

public class JuliaController extends WindowAdapter implements ActionListener {

private JuliaView view;
private JuliaModel model;
private String linkBuffer;

public JuliaController(){
    model = new JuliaModel();

    System.out.println("true!");
    view = new JuliaView("JuliaMenge");
    view.makeView();
}
@Override
public void actionPerformed(ActionEvent arg0) {
    String action = arg0.getActionCommand();
    if(action.equals(view.ACTION_CLEAR))
    {
        //Clear Graphics
        view.setBtClear();
    }
    if(action.equals(view.ACTION_COMPLEX))
    {
        String input = view.getComplex();
        view.setTfComplex();            //Zurücksetzen des Felds!

        model.juliaBerechnung(input);
        view.getBtPaint();      //Setzt den Button auf anklickbar
        //Paint Button anklickbar machen
    }
    if(action.equals(view.ACTION_ENDE))
    {
        view.release();
        System.exit(0);
    }
    if(action.equals(view.ACTION_LINK))
    {

        String inLink = view.getTfLink();
        view.setTfLink();
        try {
            model.juliaBerechnung(dataInList(inLink));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        view.getBtPaint();

    }
    if(action.equals(view.ACTION_PAINT))
    {
        //Erzeuge Graphics!

        view.getBtPaint();      //Button nicht mehr anklickbarkeit

    }

}
public String dataInList(String link)throws IOException
{
    String temp="";
    BufferedReader inBuffer = null;
    try {
        inBuffer = new BufferedReader(new FileReader(new File(link)));
        while((temp=inBuffer.readLine())!=null)
        {
            //System.out.println("Buffer : "+temp);
            linkBuffer += temp;
        }
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    int dateiLength = linkBuffer.length();
    inBuffer.close();

    char c;
    int index=0;
    for(int i = index;index<dateiLength;index++){
        c = linkBuffer.charAt(index);
        if((c=='+')||(c=='-'))break;
    }
    temp = "";
    for(int i=index;i<index+8;i++)
    {
        temp+=linkBuffer.charAt(i); 
    }
    return temp;        //Keine Anhang in der Datei
}

public void release() {
    // TODO Auto-generated method stub
    model = null;
    view = null;

}
public void windowClosing( WindowEvent we)
{
    view.release();
}

}

View:

public class JuliaView extends JFrame implements Observer{

//:::: ACTIONS
public final String ACTION_ENDE = "Ende";
public final String ACTION_PAINT = "Paint";
public final String ACTION_COMPLEX = "+a.x+b.x";
public final String ACTION_LINK = "Link";
public final String ACTION_CLEAR = "Clear";
//:::: Components
private JButton btEnde;
private JButton btPaint;
private JButton btClear;
public JuliaPanel drawArea;     //Bereich für Paint
//private JButton btAutoPaint;
private JTextField tfComplex;
private JTextField tfLink;
//:::: Observer
private JuliaModel model;
private JuliaController controller;
private JuliaBild map;



public JuliaView(String titel){
    super(titel);
    this.model = model;
    //this.map = model.getMap();            //??????//Iterationsarray einbinden
    //this.model.addObserver(this);
    //controller = makeController();
    initForm();
    //makeView();
}
void makeView() {

    resetView();

    // Fenster
    addWindowListener( controller);
    pack();
    setVisible( true);

}
/*private JuliaController makeController() {                ?????????????????
    return new JuliaController();
}*/

/**
 * Anordnen der Komponenten im GridBag
 */
private void initForm(){
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    this.setLayout(new GridBagLayout());
    this.setBounds(200, 200, 800, 600);
    GridBagConstraints c = new GridBagConstraints();
    c.insets = new Insets(15,15,15,15);
    //this.add(btAutoPaint,c);


    // TextField für Kompleze Zahl
    tfComplex = new JTextField(ACTION_COMPLEX,8);
    tfComplex.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 0;
    c.gridwidth = 2;
    this.getContentPane().add(tfComplex,c);

    // Link
    tfLink = new JTextField(ACTION_LINK);
    tfLink.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 1;
    c.gridwidth = 2;
    this.getContentPane().add(tfLink,c);
    // Paint Button
    btPaint = new JButton(ACTION_PAINT);
    btPaint.setEnabled(false);
    btPaint.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 2;
    c.gridwidth = 2;
    c.ipady = 40;
    this.getContentPane().add(btPaint,c);
    //CLS Button
    btClear = new JButton(ACTION_CLEAR);
    btClear.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 4;
    c.gridwidth = 2;
    this.getContentPane().add(btClear,c);
    //Exit Button
    btEnde = new JButton(ACTION_ENDE);
    btEnde.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 1;
    c.gridy = 5;
    c.gridwidth = 1;
    this.getContentPane().add(btEnde,c);
    //draw area
    drawArea = new JuliaPanel(); //Place for the JuliaSet
    c.fill = GridBagConstraints.HORIZONTAL; 
    c.gridx = 2;
    c.gridy = 0;
    c.gridwidth = 6;
    this.getContentPane().add(drawArea,c);
    setVisible( true);
    pack();
}
public void resetView(){
    this.tfComplex.setText("+a.x+b.x");
    this.tfLink.setText("c:/...");
    //drawArea.paint(g);
}
@Override
public void update(Observable m, Object o) {
    // TODO Auto-generated method stub
    if(model == m) setBtPaint();    //???

}
public void setBtPaint()
{
    btPaint.setText(ACTION_PAINT);
    btPaint.requestFocus();
    btPaint.setEnabled(true);
    drawArea.setKoordinaten(map);
    //Zeichnen
    //drawArea.repaint();
    drawArea.print(getGraphics());
    //drawArea.paint(getGraphics());
}
public void getBtPaint()
{
    btPaint.setText(ACTION_PAINT);
    drawArea.createImage();
    btPaint.requestFocus();
    btPaint.setEnabled(false);          //anklickbarkeit
}
public void setBtClear()
{
    btClear.setText(ACTION_CLEAR);
    resetView();
    drawArea.clearImage();
    btClear.requestFocus();
}
public void setTfComplex()
{
    tfComplex.setText(ACTION_COMPLEX);
    tfComplex.setCaretPosition(tfComplex.getText().length());
    tfComplex.requestFocus();
}
public void setTfLink()
{
    tfLink.setText(ACTION_LINK);
    tfLink.setCaretPosition(tfLink.getText().length());
    tfLink.requestFocus();
}
public void getBtEnde()
{
    btEnde.setText(ACTION_ENDE);
    btEnde.requestFocus();
}

public String getComplex()
{
    String temp = "";
    temp = tfComplex.getText();
    return temp;
}
public String getTfLink()
{
    String temp = tfLink.getText();
    return temp;
}

public void release(){

    dispose();

    // Controller
    controller.release();
    controller = null;

    // Model
    model.deleteObserver( this);
    model = null;
}

} Model:

public class JuliaModel extends Observable{
//private Complex startWert;
private Complex konst;
private String pfad;
private JuliaBild map;

public JuliaModel()
{
    //startWert = new Complex(re, im);
    konst = new Complex(1.0,1.0);
    pfad = "";
    makeBild();
}
private void makeBild()
{
    map = new JuliaBild(600,600);
    System.out.println("bild true");
}
public JuliaModel(double reK, double imK)
{
    map = new JuliaBild(600,600);
    //startWert = new Complex(re, im);
    konst = new Complex(reK,imK);
    pfad = "";
}

private int grundAlgoIt(double x,double y)
{
    Complex temp = new Complex(x,y);
    double xTemp=0;
    for(int n=0;n<256;n++)
    {
        if(temp.abs()<4){return n;}
        xTemp = Math.pow(temp.getRe(), 2)-Math.pow(temp.getIm(), 2) + konst.getRe();
        temp.setIm((2*temp.getIm()*temp.getRe())+konst.getIm());//y=
        temp.setRe(xTemp);
    }
    return 0;
}
void juliaBerechnung(String input)
{
    double xmin = -2.0;//fx
    double ymin = -2.0;//fy
    double width  =  4.0;//fw       //Weg im Koordinatensystem
    double height =  4.0;//fh
    double schrittWeite = 4.0/600;
    stringToKonst(input);
    //Complex temp = new Complex(xmin-schrittWeite,1);
    double xTemp,yTemp;
    xTemp = xmin-schrittWeite;
    //durch die Pixel gehen
    for(int j=0;j<600;j++)
    {
        xTemp = xTemp+schrittWeite;
        yTemp = ymin;
        for(int i=0;i<600;i++)
        {
            yTemp = yTemp + schrittWeite;
            map.setBild(j,i,grundAlgoIt(xTemp,yTemp));
        }
    }
}

private void stringToKonst(String in)
{
    char cBuffer;
    String sBuffer="";
    double im = 0;
    double re = 0;
    for(int a=0;a<=4;a+=4)
        for(int i=0;i<4;i++)
        {
            cBuffer = in.charAt(i+a);
            sBuffer+=cBuffer;
            if(a==0&&i==4)
            {
                re = Double.parseDouble(sBuffer);
            }
            if(a==4&&i==4)
            {
                im = Double.parseDouble(sBuffer);
            }
        }
    konst.setNumber(re, im);
}
public JuliaBild getMap()
{
    return map;
}}

Thanks for your help!

1) You're asking 3+ complex questions. Much better to ask one specific question per post here. 2) This line of code in the view makes no sense: `this.model = model;` as you're setting a null field equal to itself resulting in it remaining null. The line of code only makes sense if you're passing in a model parameter into the constructor, which you're not doing. — Hovercraft Full Of Eels, Jul 07 '15 at 23:49
I was trieing around. did it before with the same debug fails. — Ticius, Jul 07 '15 at 23:51
Regarding the update method, what specifically confuses you? — Hovercraft Full Of Eels, Jul 07 '15 at 23:53

score 4 · Answer 1 · edited Jun 20 '20 at 09:12

My actionPerformed in my controller dont react

This is because you never register you controller with anything that is capable of producing a ActionEvent

and I dont know how to use the update(model,object) method in the View.

The update method is called on behalf of your model when it's state is changed. You should update the view based on the new state of the model.

If your model supports multiple properties, a PropertyChangeListener might be better suited. If the model has different states, you might be better defining your own listener, which defines the states that the model might trigger.

But, again, it will never be called, as you never add an Observer to it

The next problem is my GridBag. It looks chaotic although the code is orientated on the oracle example.

Yep, that's GridBagLayout for you

No the Last one. in the view line 41 i get a NPE as a result of a class initialised in the Model. dont no why. I allready testes if the Class is constructed and yes it is

Which one's line 41? What's the stack trace look like?

General Advice

MVC is not an easy thing to implement within Swing, as Swing uses a form of VC-M of it's own, so you kind of end up doubling up the effort. It's not that it can't be done, but you need to think about it differently
In some forms of MVC, the controller knows about the model and view, but the model and view don't know about each other and all communication between the model and view is done via the controller. This is kinda of where the Swing implementation deviates, but you should be aware that this is how it's more commonly implemented

Start by defining the contract between the view and the controller. Define the actions that the controller can perform on the view as well as the event listeners the view is willing to accept.

Generally, I avoid attaching listeners directly to view controls from the controller and instead define events that the view can generate, in this way, you decouple the contract between the two and allow for different implementations of the view and controller to work together.

For example, if you have a button which is suppose to signify the user is read to process the input, instead of allowing the controller to directly add a ActionListener to the button, you would define a userAcceptedInput event in one of the listeners that the view supports. This way, another implementation could use some other mechanism to trigger the event, by the controller doesn't care.

For more discussions on the subject have a look at:

so the update methode is called when the action listiner is called? — Ticius, Jul 08 '15 at 07:10
Given the fact that you've haven't added a `Observer` to the `Observable`, you haven't called `setChanged` or called `notifyObservers`, then, no — MadProgrammer, Jul 08 '15 at 07:30
okay, readded the observer. i meant if should update the action listener or should i call in each setJButton/JText method setChanged/notifyObserver? — Ticius, Jul 08 '15 at 09:23
Well it depends. What expectations to you have? When would the model trigger a update event? — MadProgrammer, Jul 08 '15 at 09:32
My only great whish is that when a Button or Textfield perform an action that the set/get methods which are called in the controller do what they are supposed to do xD — Ticius, Jul 08 '15 at 09:51
Add a `addActionListener` method to your view, have it add the `ActionListener` which is passed to it added to the button and/or fields. In the controller, call said `addActionListener` method on the view and pass it a reference of a `ActionListener` — MadProgrammer, Jul 08 '15 at 09:56
okay sorry about the stupid question. I should "rewrite" the given addAchtionListener method. give it a parameter ActionListener. what to do in the method? where should i call it in the controller? — Ticius, Jul 08 '15 at 10:33
lol i think i get it. in my addactionlistener method i return the actionlistener. and in the controller i can add it? — Ticius, Jul 08 '15 at 10:37
I imagine that within your controller you're doing something like `view.addActionListener(this)` — MadProgrammer, Jul 08 '15 at 10:43
Ah now i know my problem. I had to add the Listener to the JFrame in the View. all the time i thought i had to ad it to the controller. may you help me with my NPE below too? — Ticius, Jul 08 '15 at 11:43

score 0 · Answer 2 · answered Jul 08 '15 at 10:07

Okay I added the Observer and change the constructors sothat the classes know each other. But i still dont know where/or how i should add the actionlistener to the controller because i thought i already did it when i implements it.

But now when i initialize the classes i geht this NPE:

Exception in thread "main" java.lang.NullPointerException
at JuliaView.resetView(JuliaView.java:126)
at JuliaView.makeView(JuliaView.java:57)
at JuliaController.<init>(JuliaController.java:23)
at JuliaView.<init>(JuliaView.java:44)
at Huston.main(Huston.java:10)

Here are the changed classes:

Model:

public class Huston {

//static private JuliaController missionControl;
public static void main(String[] args) {
    // TODO Auto-generated method stub


    JuliaModel model = new JuliaModel();
    JuliaView view = new JuliaView(model, "JuliaSet");
    JuliaController missionControl = new JuliaController(model, view);
}

}

Model:

public class JuliaModel extends Observable{
//private Complex startWert;
private Complex konst;
private String pfad;
private JuliaBild map;

public JuliaModel()
{
    //startWert = new Complex(re, im);
    konst = new Complex(1.0,1.0);
    pfad = "";
    makeBild();
}
private void makeBild()
{
    map = new JuliaBild(600,600);
    System.out.println("bild true");
}
public JuliaModel(double reK, double imK)
{
    map = new JuliaBild(600,600);
    //startWert = new Complex(re, im);
    konst = new Complex(reK,imK);
    pfad = "";
}

private int grundAlgoIt(double x,double y)
{
    Complex temp = new Complex(x,y);
    double xTemp=0;
    for(int n=0;n<256;n++)
    {
        if(temp.abs()<4){return n;}
        xTemp = Math.pow(temp.getRe(), 2)-Math.pow(temp.getIm(), 2) + konst.getRe();
        temp.setIm((2*temp.getIm()*temp.getRe())+konst.getIm());//y=
        temp.setRe(xTemp);
    }
    return 0;
}
void juliaBerechnung(String input)
{
    double xmin = -2.0;//fx
    double ymin = -2.0;//fy
    double width  =  4.0;//fw       //Weg im Koordinatensystem
    double height =  4.0;//fh
    double schrittWeite = 4.0/600;
    stringToKonst(input);
    //Complex temp = new Complex(xmin-schrittWeite,1);
    double xTemp,yTemp;
    xTemp = xmin-schrittWeite;
    //durch die Pixel gehen
    for(int j=0;j<600;j++)
    {
        xTemp = xTemp+schrittWeite;
        yTemp = ymin;
        for(int i=0;i<600;i++)
        {
            yTemp = yTemp + schrittWeite;
            map.setBild(j,i,grundAlgoIt(xTemp,yTemp));
        }
    }
}

private void stringToKonst(String in)
{
    char cBuffer;
    String sBuffer="";
    double im = 0;
    double re = 0;
    for(int a=0;a<=4;a+=4)
        for(int i=0;i<4;i++)
        {
            cBuffer = in.charAt(i+a);
            sBuffer+=cBuffer;
            if(a==0&&i==4)
            {
                re = Double.parseDouble(sBuffer);
            }
            if(a==4&&i==4)
            {
                im = Double.parseDouble(sBuffer);
            }
        }
    konst.setNumber(re, im);
}
public JuliaBild getMap()
{
    return map;
}}

View:

public class JuliaView extends JFrame implements Observer{

//:::: ACTIONS
public final String ACTION_ENDE = "Ende";
public final String ACTION_PAINT = "Paint";
public final String ACTION_COMPLEX = "+a.x+b.x";
public final String ACTION_LINK = "Link";
public final String ACTION_CLEAR = "Clear";
//:::: Components
private JButton btEnde;
private JButton btPaint;
private JButton btClear;
public JuliaPanel drawArea;     //Bereich für Paint
//private JButton btAutoPaint;
private JTextField tfComplex;
private JTextField tfLink;
//:::: Observer
private JuliaModel model;
private JuliaController controller;
private JuliaBild map;



public JuliaView(JuliaModel model,String titel){
    super(titel);
    this.model = model;

    //this.map = model.getMap();            //??????//Iterationsarray einbinden
    this.model.addObserver(this);
    controller = new JuliaController(model,this);

    initForm();
    //makeView();
}
void makeView() {


    // Fenster
    addWindowListener( controller);
    setVisible( true);
    pack();

    resetView();
}

/**
 * Anordnen der Komponenten im GridBag
 */
private void initForm(){
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    this.setLayout(new GridBagLayout());
    this.setBounds(200, 200, 800, 600);
    GridBagConstraints c = new GridBagConstraints();
    c.insets = new Insets(15,15,15,15);
    //this.add(btAutoPaint,c);


    // TextField für Kompleze Zahl
    tfComplex = new JTextField(ACTION_COMPLEX,8);
    tfComplex.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 0;
    c.gridwidth = 2;
    this.getContentPane().add(tfComplex,c);

    // Link
    tfLink = new JTextField(ACTION_LINK);
    tfLink.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 1;
    c.gridwidth = 2;
    this.getContentPane().add(tfLink,c);
    // Paint Button
    btPaint = new JButton(ACTION_PAINT);
    btPaint.setEnabled(false);
    btPaint.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 2;
    c.gridwidth = 2;
    c.ipady = 40;
    this.getContentPane().add(btPaint,c);
    //CLS Button
    btClear = new JButton(ACTION_CLEAR);
    btClear.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 4;
    c.gridwidth = 2;
    this.getContentPane().add(btClear,c);
    //Exit Button
    btEnde = new JButton(ACTION_ENDE);
    btEnde.addActionListener(controller);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 1;
    c.gridy = 5;
    c.gridwidth = 1;
    this.getContentPane().add(btEnde,c);
    //draw area
    drawArea = new JuliaPanel();
    c.fill = GridBagConstraints.HORIZONTAL; 
    c.gridx = 2;
    c.gridy = 0;
    c.gridwidth = 6;
    this.getContentPane().add(drawArea,c);
    setVisible( true);
    pack();
}
public void resetView(){
    this.tfComplex.setText("+a.x+b.x");
    this.tfLink.setText("c:/...");
    //drawArea.paint(g);
}
@Override
public void update(Observable m, Object o) {
    // TODO Auto-generated method stub
    if(model == m) setBtPaint();    //???

}
public void setBtPaint()
{
    btPaint.setText(ACTION_PAINT);
    btPaint.requestFocus();
    btPaint.setEnabled(true);
    drawArea.setKoordinaten(map);
    //Zeichnen
    //drawArea.repaint();
    drawArea.print(getGraphics());
    //drawArea.paint(getGraphics());
}
public void getBtPaint()
{
    btPaint.setText(ACTION_PAINT);
    drawArea.createImage();
    btPaint.requestFocus();
    btPaint.setEnabled(false);          //anklickbarkeit
}
public void setBtClear()
{
    btClear.setText(ACTION_CLEAR);
    resetView();
    drawArea.clearImage();
    btClear.requestFocus();
}
public void setTfComplex()
{
    tfComplex.setText(ACTION_COMPLEX);
    tfComplex.setCaretPosition(tfComplex.getText().length());
    tfComplex.requestFocus();
}
public void setTfLink()
{
    tfLink.setText(ACTION_LINK);
    tfLink.setCaretPosition(tfLink.getText().length());
    tfLink.requestFocus();
}
public void getBtEnde()
{
    btEnde.setText(ACTION_ENDE);
    btEnde.requestFocus();
}

public String getComplex()
{
    String temp = "";
    temp = tfComplex.getText();
    return temp;
}
public String getTfLink()
{
    String temp = tfLink.getText();
    return temp;
}

public void release(){

    dispose();

    // Controller
    controller.release();
    controller = null;

    // Model
    model.deleteObserver( this);
    model = null;
}}

Controller:

public class JuliaController extends WindowAdapter implements ActionListener {

private JuliaView view;
private JuliaModel model;
private String linkBuffer;

public JuliaController(JuliaModel model,  JuliaView view){
    this.model = model;

    this.view = view;
    view.makeView();
}
@Override
public void actionPerformed(ActionEvent arg0) {
    String action = arg0.getActionCommand();
    if(action.equals(view.ACTION_CLEAR))
    {
        //Clear Graphics
        view.setBtClear();
    }
    if(action.equals(view.ACTION_COMPLEX))
    {
        String input = view.getComplex();
        view.setTfComplex();            //Zurücksetzen des Felds!

        model.juliaBerechnung(input);
        view.getBtPaint();      //Setzt den Button auf anklickbar
        //Paint Button anklickbar machen
    }
    if(action.equals(view.ACTION_ENDE))
    {
        view.release();
        System.exit(0);
    }
    if(action.equals(view.ACTION_LINK))
    {

        String inLink = view.getTfLink();
        view.setTfLink();
        try {
            model.juliaBerechnung(dataInList(inLink));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        view.getBtPaint();

    }
    if(action.equals(view.ACTION_PAINT))
    {
        //Erzeuge Graphics!

        view.getBtPaint();      //Button nicht mehr anklickbarkeit

    }

}
public String dataInList(String link)throws IOException
{
    String temp="";
    BufferedReader inBuffer = null;
    try {
        inBuffer = new BufferedReader(new FileReader(new File(link)));
        while((temp=inBuffer.readLine())!=null)
        {
            linkBuffer += temp;
        }
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    int dateiLength = linkBuffer.length();
    inBuffer.close();

    char c;
    int index=0;
    for(int i = index;index<dateiLength;index++){
        c = linkBuffer.charAt(index);
        if((c=='+')||(c=='-'))break;
    }
    temp = "";
    for(int i=index;i<index+8;i++)
    {
        temp+=linkBuffer.charAt(i); 
    }
    return temp;        //Keine Anhang in der Datei
}

public void release() {
    // TODO Auto-generated method stub
    model = null;
    view = null;

}
public void windowClosing( WindowEvent we)
{
    view.release();
}}

ActionPerformed & update(Model,Object) in mvc and GridBagLayout

2 Answers2

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