java - Trouble populating JComboBox using getters/setters

Question

I'm having trouble generating a drop down list using an array string that I populate in the Controller class. The list displays in the GUI but contains no values. Am i using the getter/setter method incorrectly? I've been unable to find an example despite looking at the Oracle documention for JComboBoxes. The api made reference to the setModel method that I presume I'am using incorrectly. Can anyone provide a simple example?

package example;

import javax.swing.*;

public class MyApp extends JFrame {
    JTabbedPane tabbedPane = new JTabbedPane();
    View view = new View();
    ColourView colourView = new ColourView();
    Controller controller = new Controller(colourView);

public MyApp() {
    tabbedPane.add("First Tab", colourView);
    getContentPane().add(tabbedPane);
}
package example;

import javax.swing.*;

public class ColourView extends View {

private JLabel colourLabel;
private JComboBox comboBox;

public ColourView() {
    colourLabel = new JLabel();
    colourLabel.setText("Colours");
    colourLabel.setBounds(20, 30, 70, 20);
    mainContentLayeredPane.add(colourLabel, JLayeredPane.DEFAULT_LAYER);

    comboBox = new JComboBox();
    comboBox.setSize(100, 20);
    mainContentLayeredPane.add(comboBox, JLayeredPane.DEFAULT_LAYER);
}

public void setComboBox(String[] list) {
    comboBox.setModel(new DefaultComboBoxModel());
    for (Object item : list) {
        comboBox.addItem(item);
    }
}
}

public static void main(String[] args){
    SwingUtilities.invokeLater(new Runnable(){
        @Override
        public void run() {
            MyApp app = new MyApp();
            app.setVisible(true);
            app.setSize(600, 600);
            app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        }  
    });
}
}
package example;

import java.util.ListIterator;

public class Controller {

private ColourView colourView;
ListIterator<String> litr;
String listData[] = {"Item 1", "Item 2", "Item 3", "Item 4"};

Controller(ColourView colourView) {
    this.colourView = colourView;;
}

public void getListData() {
     colourView.setComboBox(listData);
}
}

score 2 · Accepted Answer

You have to add the elements to the ComboboxModel like this:

// define model
DefaultComboBoxModel model;
...

public void setComboBox(String[] list) {
    model = new DefaultComboBoxModel(list);
    comboBox.setModel(model);
}

Note: If you want to modify the Elements, you have to modify it in the model again, not in the ComboBox itself.

java - Trouble populating JComboBox using getters/setters

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