ScrollBar not working within the table cells

Question

Making use of both cell renderer and editor but still scrollbar isn't working please suggest anything that make it work scrollbar is not moving at all

class MultiRowCell extends AbstractCellEditor implements TableCellEditor, TableCellRenderer {

        private JScrollPane scrollPane;
        private JTextArea textArea;

        public MultiRowCell() {
            textArea = new JTextArea();
            textArea.setEditable(true);
            scrollPane = new JScrollPane(textArea);
        }

        @Override
        public boolean isCellEditable(EventObject e) {
            System.out.println(e);
            return true;
        }

        @Override
        public Object getCellEditorValue() {
            return textArea.getText();
        }

        protected void setCellValue(Object value) {
            if (value == null) {
                textArea.setText(null);
            } else {
                textArea.setText(value.toString());
            }
            textArea.setCaretPosition(0);
        }

        @Override
        public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
            setCellValue(value);
            return scrollPane;
        }

        @Override
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            setCellValue(value);
            return scrollPane;
        }

    }
    //TextTableCellRenderer tr=new TextTableCellRenderer();
    //table.getColumnModel().getColumn(1).setCellEditor(tr);
    MultiRowCell re=new MultiRowCell();
    table.getColumnModel().getColumn(1).setCellRenderer(re);
    table.getColumnModel().getColumn(1).setCellEditor(re);
    //table.getColumnModel().getColumn(1).setCellRenderer(r); 
    //table.getColumnModel().getColumn(1).setCellEditor(e);
    //table.getColumnModel().getColumn(2).setCellRenderer(r); 
    //table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
    panel.setLayout(new BorderLayout());
    panel.add(table, BorderLayout.CENTER);
    panel.add(table.getTableHeader(), BorderLayout.NORTH);

    return panel;

I think the first step you need to take is have a look at [Concepts: Editors and Renderers](https://docs.oracle.com/javase/tutorial/uiswing/components/table.html#editrender) to understand what a renderer actually is how a `JTable` (and other Swing components) use them. Then I think you'll need to figure out away to turn your code into a cell editor and make use of it from that direction — MadProgrammer, Sep 15 '17 at 04:23
For [example](https://stackoverflow.com/questions/9395554/scrollable-cells-in-jtable) — MadProgrammer, Sep 15 '17 at 04:35
Actualy i have tried it already but couldnot find the way out. Could you please ellaborate on this .@MadProgrammer — Sangam Jain, Sep 15 '17 at 06:09
See now i tried to add both editor as well as renderer with the cell but still nothing happens — Sangam Jain, Sep 15 '17 at 06:14
@MadProgrammer i am usng both cell render and cell editor you can see the code that i have answered below please help — Sangam Jain, Sep 15 '17 at 07:25
@MadProgrammer i have used both cell renderer and editor now but still nothing happens you can see the edited question now — Sangam Jain, Sep 18 '17 at 06:37
You will need to get the table to go into "edit" mode, typically, this will require you to tap the cell — MadProgrammer, Sep 18 '17 at 06:49
If you change the `TableModel`, you'll need to re-apply the renderer/editors — MadProgrammer, Sep 18 '17 at 09:38

MadProgrammer · Answer 1 · 2017-09-15T08:07:20.760

Conceptually you will need a cell renderer AND cell editor in order to make it work, for example...

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.EventObject;
import javax.swing.AbstractCellEditor;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellEditor;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            setLayout(new BorderLayout());

            String text = loadText();
            String[][] data = new String[1][1];
            data[0][0] = text;

            DefaultTableModel model = new DefaultTableModel(data, new String[]{"Example"});
            JTable table = new JTable(model);
            TableColumnModel columnModel =table.getColumnModel();
            TableColumn column = columnModel.getColumn(0);
            MultiRowCell multiRowCell = new MultiRowCell();
            column.setCellEditor(multiRowCell);
            column.setCellRenderer(multiRowCell);

            int height = multiRowCell.getTableCellRendererComponent(table, "Test", true, true, 0, 0).getPreferredSize().height;
            table.setRowHeight(height);

            add(new JScrollPane(table));
        }

        protected String loadText() {
            StringBuilder sb = new StringBuilder(1024);
            try (BufferedReader reader = new BufferedReader(new InputStreamReader(getClass().getResourceAsStream("Script.txt")))) {
                String text = null;
                while ((text = reader.readLine()) != null) {
                    sb.append(text).append(System.lineSeparator());
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
            return sb.toString();
        }

    }


    public class MultiRowCell extends AbstractCellEditor implements TableCellEditor, TableCellRenderer {

        private JScrollPane scrollPane;
        private JTextArea textArea;

        public MultiRowCell() {
            textArea = new JTextArea(25, 50);
            textArea.setEditable(false);
            scrollPane = new JScrollPane(textArea);
        }

        @Override
        public boolean isCellEditable(EventObject e) {
            System.out.println(e);
            return true;
        }

        @Override
        public Object getCellEditorValue() {
            return textArea.getText();
        }

        protected void setCellValue(Object value) {
            if (value == null) {
                textArea.setText(null);
            } else {
                textArea.setText(value.toString());
            }
            textArea.setCaretPosition(0);
        }

        @Override
        public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
            setCellValue(value);
            return scrollPane;
        }

        @Override
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            setCellValue(value);
            return scrollPane;
        }

    }
}

Note, I read the entire Rouge One script from a local resource for the example, you'll need to supply your own text

Caveat: This example will require you to click the cell to switch to editing mode as the mouse wheel events are been used by the scroll pane that wraps the JTable

you can see the below code not able to scroll right now also — Sangam Jain, Sep 15 '17 at 07:26
@SangamJain As I said, you may need to get the cell into "edit mode", this may require you to double tap the cell (although technically speaking, it should work with one) - this is an issue with the `JScrollPane` getting the wheel messages — MadProgrammer, Sep 15 '17 at 08:09
I cannot make it editable as the functionality requires this to be non editable @MadProgrammer — Sangam Jain, Sep 15 '17 at 08:48
@SangamJain The cell MUST be in “edit” mode - if you check my code, you’ll find I made the JTextArea non-editable — MadProgrammer, Sep 15 '17 at 08:50

ScrollBar not working within the table cells

1 Answers1