Scrollable list of JCheckBoxes

• download example.jar
• download src.zip
• repository

Code

JList

class CheckBoxCellRenderer extends JCheckBox
    implements ListCellRenderer, MouseListener, MouseMotionListener {
  @Override public Component getListCellRendererComponent(
    JList list,
    Object value,
    int index,
    boolean isSelected,
    boolean cellHasFocus) {
    this.setOpaque(true);
    if(isSelected) {
      this.setBackground(list.getSelectionBackground());
      this.setForeground(list.getSelectionForeground());
    }else{
      this.setBackground(list.getBackground());
      this.setForeground(list.getForeground());
    }
    if(value instanceof CheckBoxNode) {
      this.setSelected(((CheckBoxNode)value).selected);
      this.getModel().setRollover(index==rollOverRowIndex);
    }
    this.setText(value.toString());
    return this;
  }
  private int rollOverRowIndex = -1;
  @Override public void mouseExited(MouseEvent e) {
    JList l = (JList)e.getSource();
    if(rollOverRowIndex>=0) {
      l.repaint(l.getCellBounds(rollOverRowIndex, rollOverRowIndex));
      rollOverRowIndex = -1;
    }
  }
  @SuppressWarnings("unchecked")
  @Override public void mouseClicked(MouseEvent e) {
    if(e.getButton()==MouseEvent.BUTTON1) {
      JList l = (JList)e.getComponent();
      DefaultListModel m = (DefaultListModel)l.getModel();
      Point p = e.getPoint();
      int index  = l.locationToIndex(p);
      if(index>=0) {
        CheckBoxNode n = (CheckBoxNode)m.get(index);
        m.set(index, new CheckBoxNode(n.text, !n.selected));
        l.repaint(l.getCellBounds(index, index));
      }
    }
  }
  @Override public void mouseMoved(MouseEvent e) {
    JList l = (JList)e.getSource();
    int index = l.locationToIndex(e.getPoint());
    if(index != rollOverRowIndex) {
      rollOverRowIndex = index;
      l.repaint();
    }
  }
  @Override public void mouseEntered(MouseEvent e) {}
  @Override public void mousePressed(MouseEvent e) {}
  @Override public void mouseReleased(MouseEvent e) {}
  @Override public void mouseDragged(MouseEvent e) {}
}

JTree

class CheckBoxNodeRenderer extends JCheckBox implements TreeCellRenderer {
  private TreeCellRenderer renderer = new DefaultTreeCellRenderer();
  @Override public Component getTreeCellRendererComponent(
      JTree tree, Object value, boolean selected, boolean expanded,
      boolean leaf, int row, boolean hasFocus) {
    if(leaf && value != null && value instanceof DefaultMutableTreeNode) {
      this.setOpaque(false);
      Object userObject = ((DefaultMutableTreeNode)value).getUserObject();
      if(userObject!=null && userObject instanceof CheckBoxNode) {
        CheckBoxNode node = (CheckBoxNode)userObject;
        this.setText(node.text);
        this.setSelected(node.selected);
      }
      return this;
    }
    return renderer.getTreeCellRendererComponent(
        tree, value, selected, expanded, leaf, row, hasFocus);
  }
}

class CheckBoxNodeEditor extends JCheckBox implements TreeCellEditor {
  private final JTree tree;
  public CheckBoxNodeEditor(JTree tree) {
    super();
    this.tree = tree;
    setOpaque(false);
    setFocusable(false);
    addActionListener(new ActionListener() {
      @Override public void actionPerformed(ActionEvent e) {
        stopCellEditing();
      }
    });
  }
  @Override public Component getTreeCellEditorComponent(
      JTree tree, Object value, boolean isSelected, boolean expanded,
      boolean leaf, int row) {
    if(leaf && value != null && value instanceof DefaultMutableTreeNode) {
      Object userObject = ((DefaultMutableTreeNode)value).getUserObject();
      if(userObject!=null && userObject instanceof CheckBoxNode) {
        this.setSelected(((CheckBoxNode)userObject).selected);
      } else {
        this.setSelected(false);
      }
      this.setText(value.toString());
    }
    return this;
  }
  @Override public Object getCellEditorValue() {
    return new CheckBoxNode(getText(), isSelected());
  }
  @Override public boolean isCellEditable(EventObject e) {
    return (e != null && e instanceof MouseEvent);
  }
  //Copid from AbstractCellEditor
  //protected EventListenerList listenerList = new EventListenerList();
  //transient protected ChangeEvent changeEvent = null;
  @Override public boolean shouldSelectCell(java.util.EventObject anEvent) {
//...

References

• Scrollable list of JCheckBoxes(Japanese)