/*
* @(#)BasicComboPopup.java 1.78 04/03/05
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.swing.plaf.basic;
import javax.accessibility.AccessibleContext;
import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.border.LineBorder;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeEvent;
import java.io.Serializable;
/**
* This is a basic implementation of the ComboPopup
interface.
*
* This class represents the ui for the popup portion of the combo box.
*
* All event handling is handled by listener classes created with the
* createxxxListener()
methods and internal classes.
* You can change the behavior of this class by overriding the
* createxxxListener()
methods and supplying your own
* event listeners or subclassing from the ones supplied in this class.
*
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeansTM
* has been added to the java.beans
package.
* Please see {@link java.beans.XMLEncoder}.
*
* @version 1.78 03/05/04
* @author Tom Santos
* @author Mark Davidson
*/
public class BasicComboPopup extends JPopupMenu implements ComboPopup {
// An empty ListMode, this is used when the UI changes to allow
// the JList to be gc'ed.
private static class EmptyListModelClass implements ListModel,
Serializable {
public int getSize() { return 0; }
public Object getElementAt(int index) { return null; }
public void addListDataListener(ListDataListener l) {}
public void removeListDataListener(ListDataListener l) {}
};
static final ListModel EmptyListModel = new EmptyListModelClass();
private static Border LIST_BORDER = new LineBorder(Color.BLACK, 1);
protected JComboBox comboBox;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the accessor methods instead.
*
* @see #getList
* @see #createList
*/
protected JList list;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead
*
* @see #createScroller
*/
protected JScrollPane scroller;
/**
* As of Java 2 platform v1.4 this previously undocumented field is no
* longer used.
*/
protected boolean valueIsAdjusting = false;
// Listeners that are required by the ComboPopup interface
/**
* Implementation of all the listener classes.
*/
private Handler handler;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the accessor or create methods instead.
*
* @see #getMouseMotionListener
* @see #createMouseMotionListener
*/
protected MouseMotionListener mouseMotionListener;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the accessor or create methods instead.
*
* @see #getMouseListener
* @see #createMouseListener
*/
protected MouseListener mouseListener;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the accessor or create methods instead.
*
* @see #getKeyListener
* @see #createKeyListener
*/
protected KeyListener keyListener;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead.
*
* @see #createListSelectionListener
*/
protected ListSelectionListener listSelectionListener;
// Listeners that are attached to the list
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead.
*
* @see #createListMouseListener
*/
protected MouseListener listMouseListener;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead
*
* @see #createListMouseMotionListener
*/
protected MouseMotionListener listMouseMotionListener;
// Added to the combo box for bound properties
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead
*
* @see #createPropertyChangeListener
*/
protected PropertyChangeListener propertyChangeListener;
// Added to the combo box model
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead
*
* @see #createListDataListener
*/
protected ListDataListener listDataListener;
/**
* This protected field is implementation specific. Do not access directly
* or override. Use the create method instead
*
* @see #createItemListener
*/
protected ItemListener itemListener;
/**
* This protected field is implementation specific. Do not access directly
* or override.
*/
protected Timer autoscrollTimer;
protected boolean hasEntered = false;
protected boolean isAutoScrolling = false;
protected int scrollDirection = SCROLL_UP;
protected static final int SCROLL_UP = 0;
protected static final int SCROLL_DOWN = 1;
//========================================
// begin ComboPopup method implementations
//
/**
* Implementation of ComboPopup.show().
*/
public void show() {
setListSelection(comboBox.getSelectedIndex());
Point location = getPopupLocation();
show( comboBox, location.x, location.y );
}
/**
* Implementation of ComboPopup.hide().
*/
public void hide() {
MenuSelectionManager manager = MenuSelectionManager.defaultManager();
MenuElement [] selection = manager.getSelectedPath();
for ( int i = 0 ; i < selection.length ; i++ ) {
if ( selection[i] == this ) {
manager.clearSelectedPath();
break;
}
}
if (selection.length > 0) {
comboBox.repaint();
}
}
/**
* Implementation of ComboPopup.getList().
*/
public JList getList() {
return list;
}
/**
* Implementation of ComboPopup.getMouseListener().
*
* @return a MouseListener
or null
* @see ComboPopup#getMouseListener
*/
public MouseListener getMouseListener() {
if (mouseListener == null) {
mouseListener = createMouseListener();
}
return mouseListener;
}
/**
* Implementation of ComboPopup.getMouseMotionListener().
*
* @return a MouseMotionListener
or null
* @see ComboPopup#getMouseMotionListener
*/
public MouseMotionListener getMouseMotionListener() {
if (mouseMotionListener == null) {
mouseMotionListener = createMouseMotionListener();
}
return mouseMotionListener;
}
/**
* Implementation of ComboPopup.getKeyListener().
*
* @return a KeyListener
or null
* @see ComboPopup#getKeyListener
*/
public KeyListener getKeyListener() {
if (keyListener == null) {
keyListener = createKeyListener();
}
return keyListener;
}
/**
* Called when the UI is uninstalling. Since this popup isn't in the component
* tree, it won't get it's uninstallUI() called. It removes the listeners that
* were added in addComboBoxListeners().
*/
public void uninstallingUI() {
if (propertyChangeListener != null) {
comboBox.removePropertyChangeListener( propertyChangeListener );
}
if (itemListener != null) {
comboBox.removeItemListener( itemListener );
}
uninstallComboBoxModelListeners(comboBox.getModel());
uninstallKeyboardActions();
uninstallListListeners();
// We do this, otherwise the listener the ui installs on
// the model (the combobox model in this case) will keep a
// reference to the list, causing the list (and us) to never get gced.
list.setModel(EmptyListModel);
}
//
// end ComboPopup method implementations
//======================================
/**
* Removes the listeners from the combo box model
*
* @param model The combo box model to install listeners
* @see #installComboBoxModelListeners
*/
protected void uninstallComboBoxModelListeners( ComboBoxModel model ) {
if (model != null && listDataListener != null) {
model.removeListDataListener(listDataListener);
}
}
protected void uninstallKeyboardActions() {
// XXX - shouldn't call this method
// comboBox.unregisterKeyboardAction( KeyStroke.getKeyStroke( KeyEvent.VK_ENTER, 0 ) );
}
//===================================================================
// begin Initialization routines
//
public BasicComboPopup( JComboBox combo ) {
super();
setName("ComboPopup.popup");
comboBox = combo;
setLightWeightPopupEnabled( comboBox.isLightWeightPopupEnabled() );
// UI construction of the popup.
list = createList();
list.setName("ComboBox.list");
configureList();
scroller = createScroller();
scroller.setName("ComboBox.scrollPane");
configureScroller();
configurePopup();
installComboBoxListeners();
installKeyboardActions();
}
// Overriden PopupMenuListener notification methods to inform combo box
// PopupMenuListeners.
protected void firePopupMenuWillBecomeVisible() {
super.firePopupMenuWillBecomeVisible();
comboBox.firePopupMenuWillBecomeVisible();
}
protected void firePopupMenuWillBecomeInvisible() {
super.firePopupMenuWillBecomeInvisible();
comboBox.firePopupMenuWillBecomeInvisible();
}
protected void firePopupMenuCanceled() {
super.firePopupMenuCanceled();
comboBox.firePopupMenuCanceled();
}
/**
* Creates a listener
* that will watch for mouse-press and release events on the combo box.
*
* Warning:
* When overriding this method, make sure to maintain the existing
* behavior.
*
* @return a MouseListener
which will be added to
* the combo box or null
*/
protected MouseListener createMouseListener() {
return getHandler();
}
/**
* Creates the mouse motion listener which will be added to the combo
* box.
*
* Warning:
* When overriding this method, make sure to maintain the existing
* behavior.
*
* @return a MouseMotionListener
which will be added to
* the combo box or null
*/
protected MouseMotionListener createMouseMotionListener() {
return getHandler();
}
/**
* Creates the key listener that will be added to the combo box. If
* this method returns null then it will not be added to the combo box.
*
* @return a KeyListener
or null
*/
protected KeyListener createKeyListener() {
return null;
}
/**
* Creates a list selection listener that watches for selection changes in
* the popup's list. If this method returns null then it will not
* be added to the popup list.
*
* @return an instance of a ListSelectionListener
or null
*/
protected ListSelectionListener createListSelectionListener() {
return null;
}
/**
* Creates a list data listener which will be added to the
* ComboBoxModel
. If this method returns null then
* it will not be added to the combo box model.
*
* @return an instance of a ListDataListener
or null
*/
protected ListDataListener createListDataListener() {
return null;
}
/**
* Creates a mouse listener that watches for mouse events in
* the popup's list. If this method returns null then it will
* not be added to the combo box.
*
* @return an instance of a MouseListener
or null
*/
protected MouseListener createListMouseListener() {
return getHandler();
}
/**
* Creates a mouse motion listener that watches for mouse motion
* events in the popup's list. If this method returns null then it will
* not be added to the combo box.
*
* @return an instance of a MouseMotionListener
or null
*/
protected MouseMotionListener createListMouseMotionListener() {
return getHandler();
}
/**
* Creates a PropertyChangeListener
which will be added to
* the combo box. If this method returns null then it will not
* be added to the combo box.
*
* @return an instance of a PropertyChangeListener
or null
*/
protected PropertyChangeListener createPropertyChangeListener() {
return getHandler();
}
/**
* Creates an ItemListener
which will be added to the
* combo box. If this method returns null then it will not
* be added to the combo box.
*
* Subclasses may override this method to return instances of their own
* ItemEvent handlers.
*
* @return an instance of an ItemListener
or null
*/
protected ItemListener createItemListener() {
return getHandler();
}
private Handler getHandler() {
if (handler == null) {
handler = new Handler();
}
return handler;
}
/**
* Creates the JList used in the popup to display
* the items in the combo box model. This method is called when the UI class
* is created.
*
* @return a JList
used to display the combo box items
*/
protected JList createList() {
return new JList( comboBox.getModel() ) {
public void processMouseEvent(MouseEvent e) {
if (e.isControlDown()) {
// Fix for 4234053. Filter out the Control Key from the list.
// ie., don't allow CTRL key deselection.
e = new MouseEvent((Component)e.getSource(), e.getID(), e.getWhen(),
e.getModifiers() ^ InputEvent.CTRL_MASK,
e.getX(), e.getY(), e.getClickCount(), e.isPopupTrigger());
}
super.processMouseEvent(e);
}
};
}
/**
* Configures the list which is used to hold the combo box items in the
* popup. This method is called when the UI class
* is created.
*
* @see #createList
*/
protected void configureList() {
list.setFont( comboBox.getFont() );
list.setForeground( comboBox.getForeground() );
list.setBackground( comboBox.getBackground() );
list.setSelectionForeground( UIManager.getColor( "ComboBox.selectionForeground" ) );
list.setSelectionBackground( UIManager.getColor( "ComboBox.selectionBackground" ) );
list.setBorder( null );
list.setCellRenderer( comboBox.getRenderer() );
list.setFocusable( false );
list.setSelectionMode( ListSelectionModel.SINGLE_SELECTION );
setListSelection( comboBox.getSelectedIndex() );
installListListeners();
}
/**
* Adds the listeners to the list control.
*/
protected void installListListeners() {
if ((listMouseListener = createListMouseListener()) != null) {
list.addMouseListener( listMouseListener );
}
if ((listMouseMotionListener = createListMouseMotionListener()) != null) {
list.addMouseMotionListener( listMouseMotionListener );
}
if ((listSelectionListener = createListSelectionListener()) != null) {
list.addListSelectionListener( listSelectionListener );
}
}
void uninstallListListeners() {
if (listMouseListener != null) {
list.removeMouseListener(listMouseListener);
listMouseListener = null;
}
if (listMouseMotionListener != null) {
list.removeMouseMotionListener(listMouseMotionListener);
listMouseMotionListener = null;
}
if (listSelectionListener != null) {
list.removeListSelectionListener(listSelectionListener);
listSelectionListener = null;
}
handler = null;
}
/**
* Creates the scroll pane which houses the scrollable list.
*/
protected JScrollPane createScroller() {
JScrollPane sp = new JScrollPane( list,
ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER );
sp.setHorizontalScrollBar(null);
return sp;
}
/**
* Configures the scrollable portion which holds the list within
* the combo box popup. This method is called when the UI class
* is created.
*/
protected void configureScroller() {
scroller.setFocusable( false );
scroller.getVerticalScrollBar().setFocusable( false );
scroller.setBorder( null );
}
/**
* Configures the popup portion of the combo box. This method is called
* when the UI class is created.
*/
protected void configurePopup() {
setLayout( new BoxLayout( this, BoxLayout.Y_AXIS ) );
setBorderPainted( true );
setBorder(LIST_BORDER);
setOpaque( false );
add( scroller );
setDoubleBuffered( true );
setFocusable( false );
}
/**
* This method adds the necessary listeners to the JComboBox.
*/
protected void installComboBoxListeners() {
if ((propertyChangeListener = createPropertyChangeListener()) != null) {
comboBox.addPropertyChangeListener(propertyChangeListener);
}
if ((itemListener = createItemListener()) != null) {
comboBox.addItemListener(itemListener);
}
installComboBoxModelListeners(comboBox.getModel());
}
/**
* Installs the listeners on the combo box model. Any listeners installed
* on the combo box model should be removed in
* uninstallComboBoxModelListeners
.
*
* @param model The combo box model to install listeners
* @see #uninstallComboBoxModelListeners
*/
protected void installComboBoxModelListeners( ComboBoxModel model ) {
if (model != null && (listDataListener = createListDataListener()) != null) {
model.addListDataListener(listDataListener);
}
}
protected void installKeyboardActions() {
/* XXX - shouldn't call this method. take it out for testing.
ActionListener action = new ActionListener() {
public void actionPerformed(ActionEvent e){
}
};
comboBox.registerKeyboardAction( action,
KeyStroke.getKeyStroke( KeyEvent.VK_ENTER, 0 ),
JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT ); */
}
//
// end Initialization routines
//=================================================================
//===================================================================
// begin Event Listenters
//
/**
* A listener to be registered upon the combo box
* (not its popup menu)
* to handle mouse events
* that affect the state of the popup menu.
* The main purpose of this listener is to make the popup menu
* appear and disappear.
* This listener also helps
* with click-and-drag scenarios by setting the selection if the mouse was
* released over the list during a drag.
*
*
* Warning: * We recommend that you not * create subclasses of this class. * If you absolutely must create a subclass, * be sure to invoke the superclass * version of each method. * * @see BasicComboPopup#createMouseListener */ protected class InvocationMouseHandler extends MouseAdapter { /** * Responds to mouse-pressed events on the combo box. * * @param e the mouse-press event to be handled */ public void mousePressed( MouseEvent e ) { getHandler().mousePressed(e); } /** * Responds to the user terminating * a click or drag that began on the combo box. * * @param e the mouse-release event to be handled */ public void mouseReleased( MouseEvent e ) { getHandler().mouseReleased(e); } } /** * This listener watches for dragging and updates the current selection in the * list if it is dragging over the list. */ protected class InvocationMouseMotionHandler extends MouseMotionAdapter { public void mouseDragged( MouseEvent e ) { getHandler().mouseDragged(e); } } /** * As of Java 2 platform v 1.4, this class is now obsolete and is only included for * backwards API compatibility. Do not instantiate or subclass. *
* All the functionality of this class has been included in * BasicComboBoxUI ActionMap/InputMap methods. */ public class InvocationKeyHandler extends KeyAdapter { public void keyReleased( KeyEvent e ) {} } /** * As of Java 2 platform v 1.4, this class is now obsolete, doesn't do anything, and * is only included for backwards API compatibility. Do not call or * override. */ protected class ListSelectionHandler implements ListSelectionListener { public void valueChanged( ListSelectionEvent e ) {} } /** * As of 1.4, this class is now obsolete, doesn't do anything, and * is only included for backwards API compatibility. Do not call or * override. *
* The functionality has been migrated into ItemHandler
.
*
* @see #createItemListener
*/
public class ListDataHandler implements ListDataListener {
public void contentsChanged( ListDataEvent e ) {}
public void intervalAdded( ListDataEvent e ) {
}
public void intervalRemoved( ListDataEvent e ) {
}
}
/**
* This listener hides the popup when the mouse is released in the list.
*/
protected class ListMouseHandler extends MouseAdapter {
public void mousePressed( MouseEvent e ) {
}
public void mouseReleased(MouseEvent anEvent) {
getHandler().mouseReleased(anEvent);
}
}
/**
* This listener changes the selected item as you move the mouse over the list.
* The selection change is not committed to the model, this is for user feedback only.
*/
protected class ListMouseMotionHandler extends MouseMotionAdapter {
public void mouseMoved( MouseEvent anEvent ) {
getHandler().mouseMoved(anEvent);
}
}
/**
* This listener watches for changes to the selection in the
* combo box.
*/
protected class ItemHandler implements ItemListener {
public void itemStateChanged( ItemEvent e ) {
getHandler().itemStateChanged(e);
}
}
/**
* This listener watches for bound properties that have changed in the
* combo box.
*
* Subclasses which wish to listen to combo box property changes should * call the superclass methods to ensure that the combo popup correctly * handles property changes. * * @see #createPropertyChangeListener */ protected class PropertyChangeHandler implements PropertyChangeListener { public void propertyChange( PropertyChangeEvent e ) { getHandler().propertyChange(e); } } private class AutoScrollActionHandler implements ActionListener { private int direction; AutoScrollActionHandler(int direction) { this.direction = direction; } public void actionPerformed(ActionEvent e) { if (direction == SCROLL_UP) { autoScrollUp(); } else { autoScrollDown(); } } } private class Handler implements ItemListener, MouseListener, MouseMotionListener, PropertyChangeListener, Serializable { // // MouseListener // NOTE: this is added to both the JList and JComboBox // public void mouseClicked(MouseEvent e) { } public void mousePressed(MouseEvent e) { if (e.getSource() == list) { return; } if (!SwingUtilities.isLeftMouseButton(e) || !comboBox.isEnabled()) return; if ( comboBox.isEditable() ) { Component comp = comboBox.getEditor().getEditorComponent(); if ((!(comp instanceof JComponent)) || ((JComponent)comp).isRequestFocusEnabled()) { comp.requestFocus(); } } else if (comboBox.isRequestFocusEnabled()) { comboBox.requestFocus(); } togglePopup(); } public void mouseReleased(MouseEvent e) { if (e.getSource() == list) { // JList mouse listener comboBox.setSelectedIndex( list.getSelectedIndex() ); comboBox.setPopupVisible(false); // workaround for cancelling an edited item (bug 4530953) if (comboBox.isEditable() && comboBox.getEditor() != null) { comboBox.configureEditor(comboBox.getEditor(), comboBox.getSelectedItem()); } return; } // JComboBox mouse listener Component source = (Component)e.getSource(); Dimension size = source.getSize(); Rectangle bounds = new Rectangle( 0, 0, size.width - 1, size.height - 1 ); if ( !bounds.contains( e.getPoint() ) ) { MouseEvent newEvent = convertMouseEvent( e ); Point location = newEvent.getPoint(); Rectangle r = new Rectangle(); list.computeVisibleRect( r ); if ( r.contains( location ) ) { comboBox.setSelectedIndex( list.getSelectedIndex() ); } comboBox.setPopupVisible(false); } hasEntered = false; stopAutoScrolling(); } public void mouseEntered(MouseEvent e) { } public void mouseExited(MouseEvent e) { } // // MouseMotionListener: // NOTE: this is added to both the List and ComboBox // public void mouseMoved(MouseEvent anEvent) { if (anEvent.getSource() == list) { Point location = anEvent.getPoint(); Rectangle r = new Rectangle(); list.computeVisibleRect( r ); if ( r.contains( location ) ) { updateListBoxSelectionForEvent( anEvent, false ); } } } public void mouseDragged( MouseEvent e ) { if (e.getSource() == list) { return; } if ( isVisible() ) { MouseEvent newEvent = convertMouseEvent( e ); Rectangle r = new Rectangle(); list.computeVisibleRect( r ); if ( newEvent.getPoint().y >= r.y && newEvent.getPoint().y <= r.y + r.height - 1 ) { hasEntered = true; if ( isAutoScrolling ) { stopAutoScrolling(); } Point location = newEvent.getPoint(); if ( r.contains( location ) ) { updateListBoxSelectionForEvent( newEvent, false ); } } else { if ( hasEntered ) { int directionToScroll = newEvent.getPoint().y < r.y ? SCROLL_UP : SCROLL_DOWN; if ( isAutoScrolling && scrollDirection != directionToScroll ) { stopAutoScrolling(); startAutoScrolling( directionToScroll ); } else if ( !isAutoScrolling ) { startAutoScrolling( directionToScroll ); } } else { if ( e.getPoint().y < 0 ) { hasEntered = true; startAutoScrolling( SCROLL_UP ); } } } } } // // PropertyChangeListener // public void propertyChange(PropertyChangeEvent e) { JComboBox comboBox = (JComboBox)e.getSource(); String propertyName = e.getPropertyName(); if ( propertyName == "model" ) { ComboBoxModel oldModel = (ComboBoxModel)e.getOldValue(); ComboBoxModel newModel = (ComboBoxModel)e.getNewValue(); uninstallComboBoxModelListeners(oldModel); installComboBoxModelListeners(newModel); list.setModel(newModel); if ( isVisible() ) { hide(); } } else if ( propertyName == "renderer" ) { list.setCellRenderer( comboBox.getRenderer() ); if ( isVisible() ) { hide(); } } else if (propertyName == "componentOrientation") { // Pass along the new component orientation // to the list and the scroller ComponentOrientation o =(ComponentOrientation)e.getNewValue(); JList list = getList(); if (list!=null && list.getComponentOrientation()!=o) { list.setComponentOrientation(o); } if (scroller!=null && scroller.getComponentOrientation()!=o) { scroller.setComponentOrientation(o); } if (o!=getComponentOrientation()) { setComponentOrientation(o); } } else if (propertyName == "lightWeightPopupEnabled") { setLightWeightPopupEnabled(comboBox.isLightWeightPopupEnabled()); } } // // ItemListener // public void itemStateChanged( ItemEvent e ) { if (e.getStateChange() == ItemEvent.SELECTED) { JComboBox comboBox = (JComboBox)e.getSource(); setListSelection(comboBox.getSelectedIndex()); } } } // // end Event Listeners //================================================================= /** * Overridden to unconditionally return false. */ public boolean isFocusTraversable() { return false; } //=================================================================== // begin Autoscroll methods // /** * This protected method is implementation specific and should be private. * do not call or override. */ protected void startAutoScrolling( int direction ) { // XXX - should be a private method within InvocationMouseMotionHandler // if possible. if ( isAutoScrolling ) { autoscrollTimer.stop(); } isAutoScrolling = true; if ( direction == SCROLL_UP ) { scrollDirection = SCROLL_UP; Point convertedPoint = SwingUtilities.convertPoint( scroller, new Point( 1, 1 ), list ); int top = list.locationToIndex( convertedPoint ); list.setSelectedIndex( top ); autoscrollTimer = new Timer( 100, new AutoScrollActionHandler( SCROLL_UP) ); } else if ( direction == SCROLL_DOWN ) { scrollDirection = SCROLL_DOWN; Dimension size = scroller.getSize(); Point convertedPoint = SwingUtilities.convertPoint( scroller, new Point( 1, (size.height - 1) - 2 ), list ); int bottom = list.locationToIndex( convertedPoint ); list.setSelectedIndex( bottom ); autoscrollTimer = new Timer(100, new AutoScrollActionHandler( SCROLL_DOWN)); } autoscrollTimer.start(); } /** * This protected method is implementation specific and should be private. * do not call or override. */ protected void stopAutoScrolling() { isAutoScrolling = false; if ( autoscrollTimer != null ) { autoscrollTimer.stop(); autoscrollTimer = null; } } /** * This protected method is implementation specific and should be private. * do not call or override. */ protected void autoScrollUp() { int index = list.getSelectedIndex(); if ( index > 0 ) { list.setSelectedIndex( index - 1 ); list.ensureIndexIsVisible( index - 1 ); } } /** * This protected method is implementation specific and should be private. * do not call or override. */ protected void autoScrollDown() { int index = list.getSelectedIndex(); int lastItem = list.getModel().getSize() - 1; if ( index < lastItem ) { list.setSelectedIndex( index + 1 ); list.ensureIndexIsVisible( index + 1 ); } } // // end Autoscroll methods //================================================================= //=================================================================== // begin Utility methods // /** * Gets the AccessibleContext associated with this BasicComboPopup. * The AccessibleContext will have its parent set to the ComboBox. * * @return an AccessibleContext for the BasicComboPopup * @since 1.5 */ public AccessibleContext getAccessibleContext() { AccessibleContext context = super.getAccessibleContext(); context.setAccessibleParent(comboBox); return context; } /** * This is is a utility method that helps event handlers figure out where to * send the focus when the popup is brought up. The standard implementation * delegates the focus to the editor (if the combo box is editable) or to * the JComboBox if it is not editable. */ protected void delegateFocus( MouseEvent e ) { if ( comboBox.isEditable() ) { Component comp = comboBox.getEditor().getEditorComponent(); if ((!(comp instanceof JComponent)) || ((JComponent)comp).isRequestFocusEnabled()) { comp.requestFocus(); } } else if (comboBox.isRequestFocusEnabled()) { comboBox.requestFocus(); } } /** * Makes the popup visible if it is hidden and makes it hidden if it is * visible. */ protected void togglePopup() { if ( isVisible() ) { hide(); } else { show(); } } /** * Sets the list selection index to the selectedIndex. This * method is used to synchronize the list selection with the * combo box selection. * * @param selectedIndex the index to set the list */ private void setListSelection(int selectedIndex) { if ( selectedIndex == -1 ) { list.clearSelection(); } else { list.setSelectedIndex( selectedIndex ); list.ensureIndexIsVisible( selectedIndex ); } } protected MouseEvent convertMouseEvent( MouseEvent e ) { Point convertedPoint = SwingUtilities.convertPoint( (Component)e.getSource(), e.getPoint(), list ); MouseEvent newEvent = new MouseEvent( (Component)e.getSource(), e.getID(), e.getWhen(), e.getModifiers(), convertedPoint.x, convertedPoint.y, e.getClickCount(), e.isPopupTrigger() ); return newEvent; } /** * Retrieves the height of the popup based on the current * ListCellRenderer and the maximum row count. */ protected int getPopupHeightForRowCount(int maxRowCount) { // Set the cached value of the minimum row count int minRowCount = Math.min( maxRowCount, comboBox.getItemCount() ); int height = 0; ListCellRenderer renderer = list.getCellRenderer(); Object value = null; for ( int i = 0; i < minRowCount; ++i ) { value = list.getModel().getElementAt( i ); Component c = renderer.getListCellRendererComponent( list, value, i, false, false ); height += c.getPreferredSize().height; } return height == 0 ? 100 : height; } /** * Calculate the placement and size of the popup portion of the combo box based * on the combo box location and the enclosing screen bounds. If * no transformations are required, then the returned rectangle will * have the same values as the parameters. * * @param px starting x location * @param py starting y location * @param pw starting width * @param ph starting height * @return a rectangle which represents the placement and size of the popup */ protected Rectangle computePopupBounds(int px,int py,int pw,int ph) { Toolkit toolkit = Toolkit.getDefaultToolkit(); Rectangle screenBounds; // Calculate the desktop dimensions relative to the combo box. GraphicsConfiguration gc = comboBox.getGraphicsConfiguration(); Point p = new Point(); SwingUtilities.convertPointFromScreen(p, comboBox); if (gc != null) { Insets screenInsets = toolkit.getScreenInsets(gc); screenBounds = gc.getBounds(); screenBounds.width -= (screenInsets.left + screenInsets.right); screenBounds.height -= (screenInsets.top + screenInsets.bottom); screenBounds.x += (p.x + screenInsets.left); screenBounds.y += (p.y + screenInsets.top); } else { screenBounds = new Rectangle(p, toolkit.getScreenSize()); } Rectangle rect = new Rectangle(px,py,pw,ph); if (py+ph > screenBounds.y+screenBounds.height && ph < screenBounds.height) { rect.y = -rect.height; } return rect; } /** * Calculates the upper left location of the Popup. */ private Point getPopupLocation() { Dimension popupSize = comboBox.getSize(); Insets insets = getInsets(); // reduce the width of the scrollpane by the insets so that the popup // is the same width as the combo box. popupSize.setSize(popupSize.width - (insets.right + insets.left), getPopupHeightForRowCount( comboBox.getMaximumRowCount())); Rectangle popupBounds = computePopupBounds( 0, comboBox.getBounds().height, popupSize.width, popupSize.height); Dimension scrollSize = popupBounds.getSize(); Point popupLocation = popupBounds.getLocation(); scroller.setMaximumSize( scrollSize ); scroller.setPreferredSize( scrollSize ); scroller.setMinimumSize( scrollSize ); list.revalidate(); return popupLocation; } /** * A utility method used by the event listeners. Given a mouse event, it changes * the list selection to the list item below the mouse. */ protected void updateListBoxSelectionForEvent(MouseEvent anEvent,boolean shouldScroll) { // XXX - only seems to be called from this class. shouldScroll flag is // never true Point location = anEvent.getPoint(); if ( list == null ) return; int index = list.locationToIndex(location); if ( index == -1 ) { if ( location.y < 0 ) index = 0; else index = comboBox.getModel().getSize() - 1; } if ( list.getSelectedIndex() != index ) { list.setSelectedIndex(index); if ( shouldScroll ) list.ensureIndexIsVisible(index); } } // // end Utility methods //================================================================= }