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POObserver Pattern
 

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    <p>I would like to implement an application in which I hace two classes (a graphic one, and a controller one). Mi aim is to reflect the changes that happen in the controller class in the graphic one exactly when they occur. I need to do it by using the observer pattern, but I don't know how to get it...</p> <p>The pretended working is the following one: - In the graphic class, I have three JPanels that I want to colour with a two-second interval between each Panle is coloured.</p> <p>By now I have the following code:</p> <p>----------------------Observable class--------------------------------------------</p> <pre><code>public class ImagenControl extends Observable{ private String panel1,panel2,panel3; private int counter; private Timer colorTimer; private ActionListener colorListener=new ActionListener() { public void actionPerformed(ActionEvent ae) { if (counter==0){ panel1="yellow"; setChanged(); } else if (counter==1){ panel2="blue"; setChanged(); } else if (counter==2){ panel3="green"; setChanged(); } if (counter==2) colorTimer.stop(); else counter++; } }; public void giveColor(){ counter=0; colorTimer=new Timer(2000,colorListener); colorTimer.start(); } </code></pre> <p>---------------------------Observer class----------------------------------------</p> <pre><code>public class Imagen extends javax.swing.JFrame implements Observer{ public Imagen() { initComponents(); } private void jButton1MouseClicked(java.awt.event.MouseEvent evt) { ImagenControl ctr=new ImagenControl(); ctr.giveColor(); } public static void main(String args[]) { java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new Imagen().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JButton jButton1; private javax.swing.JPanel jPanel2; private javax.swing.JPanel jPanel3; private javax.swing.JPanel jPanel4; // End of variables declaration @Override public void update(Observable o, Object o1) { } </code></pre> <p>How would you do that??</p> <p>Thanks in advance!!</p>
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    1. USmKorbel
    1. USuser1454456
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    1. COIn MVC, Controller is never the observed one, but the observer. Events happen either in GUI or on the model and Controller routes the updates from one to the other.
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      1. USMarko Topolnik
    2. COIs this a homework exercise?
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      1. USAdam Arold
 

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