Problem while trying to open file chooser Java

Question

I am using Intellij Idea 2020.2.1 IDE for my project.

I design a simple screen which includes a file chooser to select a file.

I made it but I am not sure it is proper way to make it. I created a GUI form via "Swing UI Designer->GUI FORM". But I couldn't use this variables for screen. I need to create another Jbutton, jPanel etc.

Here is my GUI Form screen looks like.

And this my code.

public class SubtitleUploadPage implements ActionListener {
private JButton SelectSubtitleFileButton;
private JPanel fileUploadPanel;
static JLabel pathText;

public SubtitleUploadPage() {
}

public static void main(String[] args) {
    JFrame jFrame = new JFrame("File Select Screen");
    jFrame.setSize(400, 400);
    jFrame.setVisible(true);
    jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JButton selectSubtitleButton = new JButton("Select File");
    SubtitleUploadPage subtitleUploadPage = new SubtitleUploadPage();
    selectSubtitleButton.addActionListener(subtitleUploadPage);
    JPanel fileUploadPanel = new JPanel();
    fileUploadPanel.add(selectSubtitleButton);
    pathText = new JLabel("no file selected");
    fileUploadPanel.add(pathText);
    jFrame.add(fileUploadPanel);
    jFrame.setVisible(true);
}

public void actionPerformed(ActionEvent e) {
    String com = e.getActionCommand();
    if (com.equals("Select File")) {
        JFileChooser j = new JFileChooser(FileSystemView.getFileSystemView().getHomeDirectory());
        j.setAcceptAllFileFilterUsed(false);
        j.setDialogTitle("Select a .srt file");
        FileNameExtensionFilter restrict = new FileNameExtensionFilter("Only .srt files", "srt");
        j.addChoosableFileFilter(restrict);
        int r = j.showOpenDialog(null);
        if (r == JFileChooser.APPROVE_OPTION) {
            pathText.setText(j.getSelectedFile().getAbsolutePath());
        }
        else
            pathText.setText("the user cancelled the operation");
    }
}
}

And here is the result. As you can see it works as intended.

But as you can see I created Jbutton and Jpanel again. So I can't use pre-created ones.

When I try to change pre-defined Jpanel to static like:

private static JPanel fileUploadPanel;

It gives error "Cannot bind: field is static: com.convert.utf8.SubtitleUploadPage.fileUploadPanel"

If I didn't insert static keyword I can't use this Jpanel directly because main method is static.

I know my code works but I think it is not the proper way to make it. I searched it a lot I found some examples but they extends JFrame and I am pretty sure it is not the correct way either.

Could someone please show me the correct way to use a GUI element (Jbutton, Jpanel etc.) from GUI Form directly? Thanks in advance

Answer 1

I figure it out finally. Here is the code which I want to create at first place.

public class SubtitleUploadPage {
private JButton SelectSubtitleFileButton;
private JPanel fileUploadPanel;
private JLabel fileLocationLabel;

public SubtitleUploadPage() {

    SelectSubtitleFileButton.addActionListener(e -> {
        String com = e.getActionCommand();
        System.out.println(com);
        if (com.equals("Select File")) {
            JFileChooser fileChooser = new JFileChooser(FileSystemView.getFileSystemView().getHomeDirectory());
            fileChooser.setAcceptAllFileFilterUsed(false);
            fileChooser.setDialogTitle("Select a .srt file");
            FileNameExtensionFilter restrict = new FileNameExtensionFilter("Only .srt files", "srt");
            fileChooser.addChoosableFileFilter(restrict);
            int dialogResult = fileChooser.showOpenDialog(null);
            if (dialogResult == JFileChooser.APPROVE_OPTION) {
                fileLocationLabel.setText(fileChooser.getSelectedFile().getAbsolutePath());
            }
            else
                fileLocationLabel.setText("the user cancelled the operation");
        }
    });
}

public static void main(String[] args) {
    JFrame jFrame = new JFrame("File Select Screen");
    jFrame.setContentPane(new SubtitleUploadPage().fileUploadPanel);
    jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    jFrame.pack();
    jFrame.setVisible(true);
}
}