JFileChooser Thread & JLabel

Question

I'm creating a parser that's why I use JFileChooser. When I select a file with JFileChooser, I would like to have a JLabel that says : "parsing in progress" or smth like that. And when it's done : "parsing done" .

(My first aim was to use progress bars, but it's a bit complicated for me now)

The ReadFile class will take array of files and create Callable for each file. If 5 files : 5 threads will be called. I used Callable because I need to get back Strings of data for each Threads and write it in a same csv file.

Well, when I click on Cancel on JFileChooser, the JLabel displays correctly at the right moment but when I select files / file for the parsing function, the JLabel waits the entire execution of my Callables and then "processing" appears (but when it has already ended ^^).

I cannot manage to display processing at the beginning of the threads.

Note : I called CardLayout at this moment, but it is not used yet.

Here is my code :

public class Main {
    private static final String CARD_MAIN =  "Card Main";
    private static final String CARD_FILE = "Card File";    

    public static void main(String[] args) throws IOException {
        createGUI();            
    }

    public static void createGUI(){

         // the JFrame
         final JFrame window = new JFrame();
            window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            window.setLocationRelativeTo(null);
            window.setTitle("TMG Parser - Thales");
            window.setSize(400, 100);



            // the buttonPanel ( one to open JFileChooser & one to quit )
            JPanel container = new JPanel();
            JPanel buttonPanel = new JPanel(); 

            final JButton fileButton = new JButton("Choose File");
            fileButton.setBackground(Color.BLACK);
            fileButton.setForeground(Color.WHITE);

            final JButton quitButton = new JButton("Quit");
            quitButton.setBackground(Color.RED);
            quitButton.setForeground(Color.WHITE);

            // adding buttons to panel
            buttonPanel.add(fileButton);
            buttonPanel.add(quitButton);

            // the status label that says : processing or done
            final JLabel status = new JLabel();
            container.add(status);
            fileButton.addActionListener(new ActionListener()
            {
                public void actionPerformed(ActionEvent ae)
                {

                    JFileChooser dialogue = new JFileChooser(new File("."));
                    dialogue.setMultiSelectionEnabled(true) ;
                    if (dialogue.showOpenDialog(null)== 
                        JFileChooser.APPROVE_OPTION) {

                            status.setText("Processing");
                           File[] fichiers=dialogue.getSelectedFiles();
                        for( int i = 1; i<fichiers.length; ++i){ 

                            fichiers[i].getName();  
                            fichiers[i].getAbsolutePath();
                           }

                         // calling my execution function (threads)
                        ReadFile readProgram = new ReadFile(fichiers);


                    }
                    else{status.setText("Action cancelled");}
                }
            });

            quitButton.addActionListener(new ActionListener()
            {
                public void actionPerformed(ActionEvent ae)
                {
                    System.exit(0);
                }
            });
            window.add(container, BorderLayout.CENTER);
            window.add(buttonPanel, BorderLayout.PAGE_END);


            window.setVisible(true);
        }

}

Answer 1

Ok so @tobias_k was right ! Thank you man.

When I launched ReadFile, that was freezing my swing thread until ReadFile was done.

I changed ReadFile to a thread (and calling callables), and now it works perfectly. Thanks !