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Thread: i have a problem this code

  1. #1
    Junior Member
    Join Date
    Jan 2020
    Thanked 0 Times in 0 Posts

    Angry i have a problem this code

    import java.awt.BorderLayout;
    import java.awt.event.ActionEvent;
    import java.awt.event.ActionListener;
    import javax.swing.JButton;
    import javax.swing.JFrame;
    import javax.swing.JList;
    import javax.swing.JPanel;
    import javax.swing.JScrollPane;

    public class MTPSwingExample extends JFrame {

    JPanel mainPanel;
    JList list;
    JScrollPane pane;
    JButton button;
    private String label[] = {"Zero", "One", "Two", "Three", "Four", "Five", "Six",
    "Seven", "Eight", "Nine", "Ten", "Eleven"};

    public MTPSwingExample(){

    private void buildContentPane( ){
    //panoul principal
    mainPanel = new JPanel();
    mainPanel.setLayout(new BorderLayout());
    // componente
    list = new JList(label);
    pane = new JScrollPane(list);
    button = new JButton("Print");
    button.addActionListener(new PrintListener());

    mainPanel.add(pane, BorderLayout.CENTER);
    mainPanel.add(button, BorderLayout.SOUTH);

    this.setTitle("Exemplu SWING pentru MTP");
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE );
    this.setSize(300, 200);
    // An inner class to respond to clicks on the Print button

    class PrintListener implements ActionListener {
    public void actionPerformed(ActionEvent e) {
    int selected[] = list.getSelectedIndices();
    System.out.println("Selected Elements: ");

    for (int i = 0; i < selected.length; i++) {
    String element = (String)
    System.out.println(" " + element);


    public class newGui {

    public static void main(String[] args) {
    // TODO Auto-generated method stub
    MTPSwingExample mtp = new MTPSwingExample();


    when running the program tells me that

    Exception in thread "main" java.lang.Error: Unresolved compilation problem:
    The public type MTPSwingExample must be defined in its own file

    at MTPSwingExample.<init>(TutorialClass.java:10)
    at newGui.main(newGui.java:6)

    Help me !!!
    Last edited by mihaivalcea123; January 25th, 2020 at 05:46 AM.

  2. #2
    Member John Joe's Avatar
    Join Date
    Jun 2017
    My Mood
    Thanked 18 Times in 18 Posts

    Default Re: i have a problem this code

    Because you are not using it. You may remove it.
    Whatever you are, be a good one

  3. #3
    Junior Member
    Join Date
    Jan 2020
    Thanked 0 Times in 0 Posts

    Unhappy Re: i have a problem this code

    Thanks i do and try again and this code function in this moment.

    A beautiful day.

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