Application: gvSIG desktop » gvSIG Document Layout

package org.gvsig.app.project.documents.layout.fframes.gui.numberFormat;

import java.awt.event.FocusEvent;

import java.awt.event.FocusListener;

import java.util.ArrayList;

import javax.swing.JComboBox;

import org.gvsig.i18n.Messages;

/**

 * This is is a customized JComboBox used to select a single character.

 * It has the following properties:

 * <ul>

 * <li>it is editable</li>

 * <li>only allows a single char (if more chars are introduced, the string

 * is trimmed to the first character</li>

 * <li>optionally, it can show a special item (NoneItem) that represents that no

 * character wants to be selected.</li></ul>

 * 

 * @author Cesar Martinez Izquierdo

 *

 */

public class CharComboBox extends JComboBox {

        private static final long serialVersionUID = 2194202669931887456L;

        /**

         * This item represents that no item is selected

         */

        private String noneItem = Messages.getText("None");

        public CharComboBox(String[] items, boolean showNoneItem) {

                super();

                this.setEditable(true);

                for (int i=0; i<items.length; i++) {

                        String item = items[i];

                        if (item!=null && item.length()>0) {

                                this.addItem(new String(item.substring(0, 1)));

                        }

                }

                if (showNoneItem) {

                        this.addItem(noneItem);

                }

                this.addFocusListener(new FocusListener() {

                        public void focusGained(FocusEvent e) {        

                        }

                        public void focusLost(FocusEvent e) {

                                String item = getSelectedItem();

                                if (item!=null) {

                                        setSelectedItem(item);

                                }

                        }

                });

        }

        public CharComboBox() {

                this(new String[]{" "}, true);

        }

        /**

         * Returns the selected char, or null if the NoneItem is

         * selected.

         * @see javax.swing.JComboBox#getSelectedItem()

         */

        public String getSelectedItem() {

                String item = (String) super.getSelectedItem();

                if (item!=null && item!=noneItem) {

                        if (item.length()>0) {

                                return item.substring(0, 1);

                        }

                        else {

                                return " ";

                        }

                }

                else {

                        return null;

                }

        }

        // Ensure all the added items are Strings

        public void addItem(Object obj) {

                super.addItem(String.valueOf(obj));

        }

        /**

         * Sets the text to show as the NoneItem. The text has to be

         * provided in its localized form (if translations are in use).

         * 

         * @param text The localized text to show as the NoneItem

         */

        public void setNoneItemText(String text) {

                noneItem = text;

        }

}