001    /* BasicComboBoxEditor.java --
002       Copyright (C) 2004, 2005, 2006  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package javax.swing.plaf.basic;
040    
041    import java.awt.Component;
042    import java.awt.event.ActionListener;
043    import java.awt.event.FocusEvent;
044    import java.awt.event.FocusListener;
045    
046    import javax.swing.ComboBoxEditor;
047    import javax.swing.JTextField;
048    
049    /**
050     * An editor used by the {@link BasicComboBoxUI} class.  This editor uses a
051     * {@link JTextField} as the editor component.
052     *
053     * @author Olga Rodimina
054     */
055    public class BasicComboBoxEditor extends Object implements ComboBoxEditor,
056                                                               FocusListener
057    {
058      /** The editor component. */
059      protected JTextField editor;
060    
061      /**
062       * Creates a new <code>BasicComboBoxEditor</code> instance.
063       */
064      public BasicComboBoxEditor()
065      {
066        editor = new JTextField();
067        editor.setBorder(null);
068        editor.setColumns(9);
069      }
070    
071      /**
072       * Returns the component that will be used by the combo box to display and
073       * edit the currently selected item in the combo box.
074       *
075       * @return The editor component, which is a {@link JTextField} in this case.
076       */
077      public Component getEditorComponent()
078      {
079        return editor;
080      }
081    
082      /**
083       * Sets item that should be edited when any editing operation is performed
084       * by the user. The value is always equal to the currently selected value
085       * in the combo box. Thus whenever a different value is selected from the
086       * combo box list then this method should be  called to change editing
087       * item to the new selected item.
088       *
089       * @param item item that is currently selected in the combo box
090       */
091      public void setItem(Object item)
092      {
093         if (item == null)
094            editor.setText("");
095         else
096            editor.setText(item.toString());
097      }
098    
099      /**
100       * Returns the text from the editor component.
101       *
102       * @return The text from the editor component.
103       */
104      public Object getItem()
105      {
106        return editor.getText();
107      }
108    
109      /**
110       * Selects all the text in the editor component.
111       */
112      public void selectAll()
113      {
114        editor.selectAll();
115      }
116    
117      /**
118       * This method is called when textfield gains focus. This will enable
119       * editing of the selected item.
120       *
121       * @param e the FocusEvent describing change in focus.
122       */
123      public void focusGained(FocusEvent e)
124      {
125        // FIXME: Need to implement
126      }
127    
128      /**
129       * This method is called when textfield loses focus. If during this time any
130       * editting operation was performed by the user, then it will be cancelled
131       * and selected item will not be changed.
132       *
133       * @param e the FocusEvent describing change in focus
134       */
135      public void focusLost(FocusEvent e)
136      {
137        // FIXME: Need to implement
138      }
139    
140      /**
141       * Adds an {@link ActionListener} to the editor component.  If the user will
142       * edit currently selected item in the textfield and pressEnter, then action
143       * will be performed. The actionPerformed of this ActionListener should
144       * change the selected item of the comboBox to the newly editted  selected
145       * item.
146       *
147       * @param l the ActionListener responsible for changing selected item of the
148       *        combo box when it is editted by the user.
149       */
150      public void addActionListener(ActionListener l)
151      {
152        editor.addActionListener(l);
153      }
154    
155      /**
156       * Removes the {@link ActionListener} from the editor component.
157       *
158       * @param l the listener to remove.
159       */
160      public void removeActionListener(ActionListener l)
161      {
162        editor.removeActionListener(l);
163      }
164    
165      /**
166       * A subclass of {@link BasicComboBoxEditor} that implements the
167       * {@link UIResource} interface.
168       */
169      public static class UIResource extends BasicComboBoxEditor
170        implements javax.swing.plaf.UIResource
171      {
172        /**
173         * Creates a new <code>BasicComboBoxEditor.UIResource</code> instance.
174         */
175        public UIResource()
176        {
177          // Nothing to do here.
178        }
179      }
180    
181    }