Checkbox items in combox rendering

[charanjeet_sm]

Hi All,
I am trying to show checkboxes in combobox i.e. each element in the combobox will be a checkbox so that user can select multiple options in the combobox. This will be same as "AutoFilter Option in MS Excel 2007". After much googling around, I have the following solution with only one issue pending:

import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.BorderLayout;
import javax.swing.JComboBox;
import java.awt.event.ActionEvent;
import javax.swing.JList;
import javax.swing.ListCellRenderer;
import javax.swing.JCheckBox;
import java.awt.Component;
import java.awt.Color;

public class CheckCombo1
    extends JFrame {

  JPanel buttonPanel;
  CheckCombo checkCombo;

  public CheckCombo1() {

    buttonPanel = new JPanel();
    checkCombo = new CheckCombo();
    checkCombo.addItem(new CheckComboStore("Item-A", true));
    checkCombo.addItem(new CheckComboStore("Item-B", true));
    checkCombo.addItem(new CheckComboStore("Item-C", true));
    buttonPanel.add(checkCombo);
    getContentPane().add(buttonPanel, BorderLayout.NORTH);

    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setSize(650, 250);
    setVisible(true);
  }

  public static void main(String args[]) {
    CheckCombo1 fe = new CheckCombo1();
  }

  class CheckCombo
      extends JComboBox {
    CheckComboRenderer renderer;
    public CheckCombo() {
      renderer = new CheckComboRenderer();
      setRenderer(renderer);
      addActionListener(this);
    }

    public void actionPerformed(ActionEvent e) {
      System.out.println("action");
      CheckComboStore store = (CheckComboStore) getSelectedItem();
//      CheckComboRenderer ccr = (CheckComboRenderer) getRenderer();
      store.state = !store.state;
//      ccr.checkBox.setSelected(store.state);
      repaint();
    }

    public void setPopupVisible(boolean flag) {
    }

  }

  class CheckComboRenderer
      implements ListCellRenderer {
    JCheckBox checkBox;

    public CheckComboRenderer() {
      checkBox = new JCheckBox();
//      checkBox.addActionListener(new java.awt.event.ActionListener() {
//        public void actionPerformed(ActionEvent e) {
//          System.out.println("here");
//        }
//      }
//      );
    }

    public Component getListCellRendererComponent(JList list,
                                                  Object value,
                                                  int index,
                                                  boolean isSelected,
                                                  boolean cellHasFocus) {
      CheckComboStore store = (CheckComboStore) value;
      System.out.println("text=" + store.id + " state=" +
                         store.state.booleanValue());
      checkBox.setText(store.id);
      checkBox.setSelected( ( (Boolean) store.state).booleanValue());
      checkBox.setBackground(isSelected ? Color.red : Color.white);
      checkBox.setForeground(isSelected ? Color.white : Color.black);
      return checkBox;
    }
  }

  class CheckComboStore {
    String id;
    Boolean state;

    public CheckComboStore(String id, Boolean state) {
      this.id = id;
      this.state = state;
    }
  }
}

When you run the above code, you will see a combo box with three elements, "Item-A", "Item-B" and "Item-C". All the three elements are checkboxes so that user can select multiple options. However, if you will select the option which is already selected in the combobox, its checkbox will not be rendered correctly, even though the state of the checkbox has changed correctly.
Ex: On running the sample application, if you open the combobox and select the "Item-A", its checkbox will not be rendered correctly. If you move the mouse over other item (with pop up already opened), you will see the state of the "Item-A" checkbox has indeed changed but it is not showing correctly. The same thing happens whenever you select a already selected item in the combobox. It seems there is some rendering issue.
Please help.
Thanks,
Charanjeet

[DarrylBurke]

Cross posted
Checkbox items incombobox rendering (Swing / AWT / SWT / JFace forum at JavaRanch)

Any more?

db

edit http://forums.oracle.com/forums/thre...readID=2143880

[hosscomp]

I am trying to show checkboxes in combobox i.e. each element in the combobox will be a checkbox so that user can select multiple options in the combobox.

The combobox was designed to show one selected item. I would think the preferred solution for multiple selections would be a JList in multi-selection mode or a group of check boxes in a JPanel. Either can have a scroll bar and/or be placed in a popup dialog if realestate is a problem.