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copied!<p>You can use a custom class like this one (run main function to see its behavior) :</p> <pre><code>import java.awt.BorderLayout; import java.awt.Component; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.ArrayList; import java.util.Collection; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Set; import java.util.TreeMap; import javax.swing.AbstractListModel; import javax.swing.ComboBoxModel; import javax.swing.DefaultListCellRenderer; import javax.swing.JComboBox; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JList; import javax.swing.JPanel; public class KeyValueComboboxModel extends AbstractListModel implements ComboBoxModel, Map<String, String> { private TreeMap<String,String> values = new TreeMap<String,String>(); private Map.Entry<String, String> selectedItem = null; public Object getSelectedItem() { return selectedItem; } public void setSelectedItem(Object anItem) { this.selectedItem = (java.util.Map.Entry<String, String>) anItem; fireContentsChanged(this, -1, -1); } public Object getElementAt(int index) { List<Map.Entry<String, String>> list = new ArrayList<Map.Entry<String, String>>(values.entrySet()); return list.get(index); } public int getSize() { return values.size(); } public void clear() { values.clear(); } public boolean containsKey(Object key) { return values.containsKey(key); } public boolean containsValue(Object value) { return values.containsValue(value); } public Set<java.util.Map.Entry<String, String>> entrySet() { return values.entrySet(); } public String get(Object key) { return values.get(key); } public Set<String> keySet() { return values.keySet(); } public String put(String key, String value) { return values.put(key, value); } public String remove(Object key) { return values.remove(key); } public int size() { return values.size(); } public Collection<String> values() { return values.values(); } public boolean isEmpty() { return values.isEmpty(); } public void putAll(Map<? extends String, ? extends String> m) { values.putAll(m); } private static String entryToString(Map.Entry<String, String> entry) { String str = "" + entry.getKey() + "->" + entry.getValue(); return str; } public static void main(String[] args) { Map<String,String> map= new HashMap<String,String>(){{ put("1","blue"); put("2","red"); put("3","white"); put("4","black"); }}; JFrame f = new JFrame(); f.setContentPane(new JPanel(new BorderLayout())); KeyValueComboboxModel model = new KeyValueComboboxModel(); model.putAll(map); final JComboBox combo = new JComboBox(model); combo.setRenderer(new DefaultListCellRenderer(){ @Override public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) { if(value instanceof Map.Entry){ Map.Entry<String,String> entry = (java.util.Map.Entry<String, String>) value; String str = entryToString(entry); return super.getListCellRendererComponent(list, str, index, isSelected, cellHasFocus); } return super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); } }); final JLabel lab = new JLabel("Nothing selected"); combo.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { if(combo.getSelectedItem()!=null){ lab.setText(entryToString((java.util.Map.Entry<String, String>) combo.getSelectedItem())); } else { lab.setText(""); } } }); f.getContentPane().add(combo,BorderLayout.CENTER); f.getContentPane().add(lab,BorderLayout.SOUTH); f.setSize(300,80); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setLocationRelativeTo(null); f.setVisible(true); } } </code></pre> <p>EDIT : to handle the selected item and keys, you may add these methods:</p> <pre><code>public void setSelectedKey(String key){ selectedItem = values.ceilingEntry(key); setSelectedItem(key); } public void setSelectedItem(String key, String value){ values.put(key, value); setSelectedKey(key); } </code></pre> <p>By default, values are ordered following the natural order of the keys (alphabetical order of the keys, here, because these are <code>String</code>). If you need an other ordering, add a <code>java.util.Comparator</code> to the <code>TreeMap</code> (see TreeMap documentation).</p>

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