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Split list in Java / Swing?

I have a list of items in JList

for a user to select. Since it has a lot of items (like cities within states), I want to split the list into sections. However, section titles should not be selectable. So for my cities / states example, it might look like this:

  • Condition 1
    • City 1
    • City 2
    • City 3
  • Condition 2
    • City 4
    • City 5
    • City 6

It wouldn't be that hard to write this myself by pasting JList

in a custom one ListCellRenderer

, but I'm wondering if such a class already exists there.

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4 answers


I see that this question has already been answered, but I noticed Robert commented that he hopes for an open source solution. I would recommend using the Separator Glazed Lists, the API for which you can find here:

http://publicobject.com/glazedlists/glazedlists-1.8.0/api/ca/odell/glazedlists/SeparatorList.html

Here is some sample code that will create a list of items grouped by their first letter:



alt text http://img300.imageshack.us/img300/8977/separatorlist.png

public class SeparatorListTest {

private static Comparator<String> createComparator() {
    return new Comparator<String>() {
        public int compare(String stringOne, String stringTwo) {
            return stringOne.substring(0,1).compareTo(stringTwo.substring(0,1));
        }
    };
}

private static ListCellRenderer createListCellRenderer() {
    return new DefaultListCellRenderer() {
        @Override
        public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
            JLabel label = (JLabel) super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);

            if (value instanceof SeparatorList.Separator) {
                SeparatorList.Separator separator = (SeparatorList.Separator) value;
                label.setText(separator.getGroup().get(0).toString().substring(0,1));
                label.setFont(label.getFont().deriveFont(Font.BOLD));
                label.setBorder(BorderFactory.createEmptyBorder(0,5,0,0));
            } else {
                label.setFont(label.getFont().deriveFont(Font.PLAIN));
                label.setBorder(BorderFactory.createEmptyBorder(0,15,0,0));
            }

            return label;
        }
    };
}

public static void main(String[] args) {
    EventList<String> rawList = GlazedLists.eventListOf(
            "apple", "appricot", "acorn", "blueberry", "coconut", "chesnut", "grape");
    SeparatorList<String> separatorList = 
            new SeparatorList<String>(rawList, createComparator(), 1, 1000);

    JList list = new JList(new EventListModel<String>(separatorList));
    list.setCellRenderer(createListCellRenderer());
    JScrollPane scrollPane = new JScrollPane(list);
    scrollPane.setBorder(null);

    JFrame frame = new JFrame();
    frame.add(scrollPane, BorderLayout.CENTER);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(200,200);
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);
}

}

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There is a component available with JIDE that allows you to do just that. It was called GroupList:



alt text

+4


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Perhaps using JTree ? What you are describing is a tree with two levels.

+3


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You can use what Apple calls SourceList. You can see them in action in iTunes and the Mac OS X Finder. This is an elegant solution to the problem you are describing.

An open source cross-platform Java Swing component for this can be found here: http://explodingpixels.wordpress.com/2008/09/08/mac-widgets-for-java/

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