private void showFileOpenDialog(){
        JFileChooser fileOpen = new JFileChooser("./");
//        FileNameExtensionFilter filter = new FileNameExtensionFilter(
//                "Algorythm workspace files .wks", "wks");
//        fileOpen.setFileFilter(filter);
        int ret = fileOpen.showDialog(null, "Open file");
        if (ret == JFileChooser.APPROVE_OPTION) {
            importingFile = fileOpen.getSelectedFile();
            if(Main.setListAllWords(importingFile)){
                JOptionPane.showMessageDialog(frame, "Import success!", "Import file",JOptionPane.INFORMATION_MESSAGE);
                nameCurrentSubject = importingFile.getName();
                showMessage(subject,nameCurrentSubject);
            }
            else{
                JOptionPane.showMessageDialog(frame, "Import filed!", "Import file",JOptionPane.ERROR_MESSAGE);
            }

        }
//        FileDialog fileDialog = new FileDialog(this, "Open file",FileDialog.LOAD);
//        fileDialog.setLocation((int)(SCREEN_SIZE.getWidth()/2-getWidth()/2),
//                (int)(SCREEN_SIZE.getHeight()/2-getHeight()/2));
//        fileDialog.setDirectory("./");
//        fileDialog.setVisible(true);
//
//        importingFile = new File(fileDialog.getDirectory()+fileDialog.getFile());
//        if(importingFile.getPath().equals("nullnull"))
//            return;
//        if(com.wr.Main.setListAllWords(importingFile))
//                JOptionPane.showMessageDialog(this, "Import success!", "Import file",JOptionPane.INFORMATION_MESSAGE);
//            else
//                JOptionPane.showMessageDialog(this, "Import filed!", "Import file",JOptionPane.ERROR_MESSAGE);

    }