I have already a collection(List) of sentences. So I need to put every single sentences in a check box.The number of check boxes depends on the number of Vector Size. For example, I have 50 sentences, so I need 50 check boxes. Then user can check the desired sentences to be written in a text file.
The following class (ViewerFrame) is supposed to build a frame to have many checkboxes the same as the number of sentences in the array list(ManualSummarySys.sentences).Class (ManualSummarySys) is working perfectly.

```
public class ViewerFrame {

import java.awt.BorderLayout ;
import java.awt.Font ;
import java.awt.GridLayout ;
import java.awt.ScrollPane ;
import java.awt.event.ActionEvent ;
import java.awt.event.ActionListener ;
import java.util.ArrayList ;
import java.util.List ;
import javax.swing.ButtonGroup ;
import javax.swing.JButton ;
import javax.swing.JCheckBox ;
import javax.swing.JComboBox ;
import javax.swing.JFrame ;
import javax.swing.JLabel ;
import javax.swing.JPanel ;
import javax.swing.JRadioButton ;
import javax.swing.border.EtchedBorder ;
import javax.swing.border.TitledBorder ;
import javax.swing.plaf.metal.MetalBorders ;

public class ViewerFrame extends JFrame {

    private static final int FRAME_WIDTH = 10;
    private static final int FRAME_HEIGHT = 5;
    private JLabel sampleField;
    private List<JCheckBox> checkboxes = new ArrayList<JCheckBox>();
    private ActionListener listener;

    public ViewerFrame() {

        sampleField = new JLabel("choose your prefered sentences");
        add(sampleField, BorderLayout.WEST);

        class ChoiceListener implements ActionListener {

            public void actionPerformed(ActionEvent event) {
            }
        }
        listener = new ChoiceListener();
        createControlPanel();

        setSize(FRAME_WIDTH, FRAME_HEIGHT);
        add(this.createCheckBoxes());

    }

    public void createControlPanel() {
        JFrame sizeGroupPanel = createCheckBoxes();

        JPanel controlPanel = new JPanel();
        controlPanel.setLayout(new GridLayout(3, 1));

        controlPanel.add(sizeGroupPanel);
        controlPanel.add(styleGroupPanel);

        add(controlPanel, BorderLayout.LINE_START);

    }

    public JFrame createCheckBoxes() {
        JFrame frame = new JFrame("Sentences");
        frame.setBorder(new TitledBorder(new EtchedBorder(), "Sentences"));
        for (int i = 0; i < ManualSummarySys.sentences.size(); i++) {
            JCheckBox checkbox = new JCheckBox(ManualSummarySys.sentences.get(i));
            checkboxes.add(checkbox);
            checkbox.addActionListener(listener);
            frame.add(checkbox);

        }
        return frame;
    }
}

```