Question

I am looking for code that will add favorites / MRU type behavior to a JComboBox.

I could code this myself, but it sure seems like someone else has probably already done it.

I found the following (which looks exactly like what I want, but the source code is nowhere near complete): http://java.sys-con.com/node/36658

Any suggestions? I need to keep this relatively light, so I’d prefer to not use a component that’s part of a monolithic widget library, and open source is preferred.

Answer 1

Consider extending DefaultComboBoxModel: override addElement() and insertElementAt() to insert at zero and remove the last element.

Addendum: Here’s an example; per SO, the license is cc-wiki. I’d use Preferences to persist the entries.

class MRUComboBoxModel extends DefaultComboBoxModel {

    @Override
    public void addElement(Object element) {
        this.insertElementAt(element, 0);
    }

    @Override
    public void insertElementAt(Object element, int index) {
        super.insertElementAt(element, 0);
        int size = this.getSize();
        if (size > 10) {
            this.removeElementAt(size - 1);
        }
    }
}