javax.swing.plaf.basic
Class BasicComboPopup

java.lang.Object
  java.awt.Component
      java.awt.Container
          javax.swing.JComponent
              javax.swing.JPopupMenu
                  javax.swing.plaf.basic.BasicComboPopup

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible, MenuElement, ComboPopup

Direct Known Subclasses:

MetalComboBoxUI.MetalComboPopup

public class BasicComboPopup
extends JPopupMenu
implements ComboPopup

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 JavaBeans^TM has been added to the java.beans package. Please see XMLEncoder.

Nested Class Summary

class	BasicComboPopup.InvocationKeyHandler As of Java 2 platform v 1.4, this class is now obsolete and is only included for backwards API compatibility.
protected class	BasicComboPopup.InvocationMouseHandler 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.
protected class	BasicComboPopup.InvocationMouseMotionHandler This listener watches for dragging and updates the current selection in the list if it is dragging over the list.
protected class	BasicComboPopup.ItemHandler This listener watches for changes to the selection in the combo box.
class	BasicComboPopup.ListDataHandler As of 1.4, this class is now obsolete, doesn't do anything, and is only included for backwards API compatibility.
protected class	BasicComboPopup.ListMouseHandler This listener hides the popup when the mouse is released in the list.
protected class	BasicComboPopup.ListMouseMotionHandler This listener changes the selected item as you move the mouse over the list.
protected class	BasicComboPopup.ListSelectionHandler 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.
protected class	BasicComboPopup.PropertyChangeHandler This listener watches for bound properties that have changed in the combo box.

Nested classes/interfaces inherited from class javax.swing.JPopupMenu

JPopupMenu.AccessibleJPopupMenu, JPopupMenu.Separator

Nested classes/interfaces inherited from class javax.swing.JComponent

JComponent.AccessibleJComponent

Nested classes/interfaces inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

protected Timer	autoscrollTimer This protected field is implementation specific.
protected JComboBox	comboBox
protected boolean	hasEntered
protected boolean	isAutoScrolling
protected ItemListener	itemListener This protected field is implementation specific.
protected KeyListener	keyListener This protected field is implementation specific.
protected JList	list This protected field is implementation specific.
protected ListDataListener	listDataListener This protected field is implementation specific.
protected MouseListener	listMouseListener This protected field is implementation specific.
protected MouseMotionListener	listMouseMotionListener This protected field is implementation specific.
protected ListSelectionListener	listSelectionListener This protected field is implementation specific.
protected MouseListener	mouseListener This protected field is implementation specific.
protected MouseMotionListener	mouseMotionListener This protected field is implementation specific.
protected PropertyChangeListener	propertyChangeListener This protected field is implementation specific.
protected static int	SCROLL_DOWN
protected static int	SCROLL_UP
protected int	scrollDirection
protected JScrollPane	scroller This protected field is implementation specific.
protected boolean	valueIsAdjusting As of Java 2 platform v1.4 this previously undocumented field is no longer used.

Fields inherited from class javax.swing.JComponent

accessibleContext, listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

BasicComboPopup(JComboBox combo)

Method Summary

protected void	autoScrollDown() This protected method is implementation specific and should be private.
protected void	autoScrollUp() This protected method is implementation specific and should be private.
protected Rectangle	computePopupBounds(int px, int py, int pw, int ph) Calculate the placement and size of the popup portion of the combo box based on the combo box location and the enclosing screen bounds.
protected void	configureList() Configures the list which is used to hold the combo box items in the popup.
protected void	configurePopup() Configures the popup portion of the combo box.
protected void	configureScroller() Configures the scrollable portion which holds the list within the combo box popup.
protected MouseEvent	convertMouseEvent(MouseEvent e)
protected ItemListener	createItemListener() Creates an ItemListener which will be added to the combo box.
protected KeyListener	createKeyListener() Creates the key listener that will be added to the combo box.
protected JList	createList() Creates the JList used in the popup to display the items in the combo box model.
protected ListDataListener	createListDataListener() Creates a list data listener which will be added to the ComboBoxModel.
protected MouseListener	createListMouseListener() Creates a mouse listener that watches for mouse events in the popup's list.
protected MouseMotionListener	createListMouseMotionListener() Creates a mouse motion listener that watches for mouse motion events in the popup's list.
protected ListSelectionListener	createListSelectionListener() Creates a list selection listener that watches for selection changes in the popup's list.
protected MouseListener	createMouseListener() Creates a listener that will watch for mouse-press and release events on the combo box.
protected MouseMotionListener	createMouseMotionListener() Creates the mouse motion listener which will be added to the combo box.
protected PropertyChangeListener	createPropertyChangeListener() Creates a PropertyChangeListener which will be added to the combo box.
protected JScrollPane	createScroller() Creates the scroll pane which houses the scrollable list.
protected void	delegateFocus(MouseEvent e) This is is a utility method that helps event handlers figure out where to send the focus when the popup is brought up.
protected void	firePopupMenuCanceled() Notifies PopupMenuListeners that this popup menu is cancelled.
protected void	firePopupMenuWillBecomeInvisible() Notifies PopupMenuListeners that this popup menu will become invisible.
protected void	firePopupMenuWillBecomeVisible() Notifies PopupMenuListeners that this popup menu will become visible.
AccessibleContext	getAccessibleContext() Gets the AccessibleContext associated with this BasicComboPopup.
KeyListener	getKeyListener() Implementation of ComboPopup.getKeyListener().
JList	getList() Implementation of ComboPopup.getList().
MouseListener	getMouseListener() Implementation of ComboPopup.getMouseListener().
MouseMotionListener	getMouseMotionListener() Implementation of ComboPopup.getMouseMotionListener().
protected int	getPopupHeightForRowCount(int maxRowCount) Retrieves the height of the popup based on the current ListCellRenderer and the maximum row count.
void	hide() Implementation of ComboPopup.hide().
protected void	installComboBoxListeners() This method adds the necessary listeners to the JComboBox.
protected void	installComboBoxModelListeners(ComboBoxModel model) Installs the listeners on the combo box model.
protected void	installKeyboardActions()
protected void	installListListeners() Adds the listeners to the list control.
boolean	isFocusTraversable() Overridden to unconditionally return false.
void	show() Implementation of ComboPopup.show().
protected void	startAutoScrolling(int direction) This protected method is implementation specific and should be private.
protected void	stopAutoScrolling() This protected method is implementation specific and should be private.
protected void	togglePopup() Makes the popup visible if it is hidden and makes it hidden if it is visible.
protected void	uninstallComboBoxModelListeners(ComboBoxModel model) Removes the listeners from the combo box model
void	uninstallingUI() Called when the UI is uninstalling.
protected void	uninstallKeyboardActions()
protected void	updateListBoxSelectionForEvent(MouseEvent anEvent, boolean shouldScroll) A utility method used by the event listeners.

Methods inherited from class javax.swing.JPopupMenu

add, add, add, addMenuKeyListener, addPopupMenuListener, addSeparator, createActionChangeListener, createActionComponent, getComponent, getComponentAtIndex, getComponentIndex, getDefaultLightWeightPopupEnabled, getInvoker, getLabel, getMargin, getMenuKeyListeners, getPopupMenuListeners, getSelectionModel, getSubElements, getUI, getUIClassID, insert, insert, isBorderPainted, isLightWeightPopupEnabled, isPopupTrigger, isVisible, menuSelectionChanged, pack, paintBorder, paramString, processFocusEvent, processKeyEvent, processKeyEvent, processMouseEvent, remove, removeMenuKeyListener, removePopupMenuListener, setBorderPainted, setDefaultLightWeightPopupEnabled, setInvoker, setLabel, setLightWeightPopupEnabled, setLocation, setPopupSize, setPopupSize, setSelected, setSelectionModel, setUI, setVisible, show, updateUI

Methods inherited from class javax.swing.JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, unregisterKeyboardAction, update

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusBackward, transferFocusDownCycle, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setName, setSize, setSize, show, size, toString, transferFocus, transferFocusUpCycle

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface javax.swing.plaf.basic.ComboPopup

isVisible

Field Detail

comboBox

protected JComboBox comboBox

list

protected JList list

This protected field is implementation specific. Do not access directly or override. Use the accessor methods instead.

See Also:

getList(), createList()

scroller

protected JScrollPane scroller

This protected field is implementation specific. Do not access directly or override. Use the create method instead

See Also:

createScroller()

valueIsAdjusting

protected boolean valueIsAdjusting

As of Java 2 platform v1.4 this previously undocumented field is no longer used.

mouseMotionListener

protected MouseMotionListener mouseMotionListener

This protected field is implementation specific. Do not access directly or override. Use the accessor or create methods instead.

See Also:

getMouseMotionListener(), createMouseMotionListener()

mouseListener

protected MouseListener mouseListener

This protected field is implementation specific. Do not access directly or override. Use the accessor or create methods instead.

See Also:

getMouseListener(), createMouseListener()

keyListener

protected KeyListener keyListener

This protected field is implementation specific. Do not access directly or override. Use the accessor or create methods instead.

See Also:

getKeyListener(), createKeyListener()

listSelectionListener

protected ListSelectionListener listSelectionListener

This protected field is implementation specific. Do not access directly or override. Use the create method instead.

See Also:

createListSelectionListener()

listMouseListener

protected MouseListener listMouseListener

This protected field is implementation specific. Do not access directly or override. Use the create method instead.

See Also:

createListMouseListener()

listMouseMotionListener

protected MouseMotionListener listMouseMotionListener

This protected field is implementation specific. Do not access directly or override. Use the create method instead

See Also:

createListMouseMotionListener()

propertyChangeListener

protected PropertyChangeListener propertyChangeListener

This protected field is implementation specific. Do not access directly or override. Use the create method instead

See Also:

createPropertyChangeListener()

listDataListener

protected ListDataListener listDataListener

This protected field is implementation specific. Do not access directly or override. Use the create method instead

See Also:

createListDataListener()

itemListener

protected ItemListener itemListener

This protected field is implementation specific. Do not access directly or override. Use the create method instead

See Also:

createItemListener()

autoscrollTimer

protected Timer autoscrollTimer

This protected field is implementation specific. Do not access directly or override.

hasEntered

protected boolean hasEntered

isAutoScrolling

protected boolean isAutoScrolling

scrollDirection

protected int scrollDirection

SCROLL_UP

protected static final int SCROLL_UP

See Also:

Constant Field Values

SCROLL_DOWN

protected static final int SCROLL_DOWN

See Also:

Constant Field Values

Constructor Detail

BasicComboPopup

public BasicComboPopup(JComboBox combo)

Method Detail

show

public void show()

Implementation of ComboPopup.show().

Specified by:

show in interface ComboPopup

Overrides:

show in class Component

hide

public void hide()

Implementation of ComboPopup.hide().

Specified by:

hide in interface ComboPopup

Overrides:

hide in class Component

getList

public JList getList()

Implementation of ComboPopup.getList().

Specified by:

getList in interface ComboPopup

getMouseListener

public MouseListener getMouseListener()

Implementation of ComboPopup.getMouseListener().

Specified by:

getMouseListener in interface ComboPopup

Returns:

a MouseListener or null

See Also:

ComboPopup.getMouseListener()

getMouseMotionListener

public MouseMotionListener getMouseMotionListener()

Implementation of ComboPopup.getMouseMotionListener().

Specified by:

getMouseMotionListener in interface ComboPopup

Returns:

a MouseMotionListener or null

See Also:

ComboPopup.getMouseMotionListener()

getKeyListener

public KeyListener getKeyListener()

Implementation of ComboPopup.getKeyListener().

Specified by:

getKeyListener in interface ComboPopup

Returns:

a KeyListener or null

See Also:

ComboPopup.getKeyListener()

uninstallingUI

public void uninstallingUI()

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().

Specified by:

uninstallingUI in interface ComboPopup

uninstallComboBoxModelListeners

protected void uninstallComboBoxModelListeners(ComboBoxModel model)

Removes the listeners from the combo box model

Parameters:

model - The combo box model to install listeners

See Also:

installComboBoxModelListeners(javax.swing.ComboBoxModel)

uninstallKeyboardActions

protected void uninstallKeyboardActions()

firePopupMenuWillBecomeVisible

protected void firePopupMenuWillBecomeVisible()

Description copied from class: JPopupMenu

Notifies PopupMenuListeners that this popup menu will become visible.

Overrides:

firePopupMenuWillBecomeVisible in class JPopupMenu

firePopupMenuWillBecomeInvisible

protected void firePopupMenuWillBecomeInvisible()

Description copied from class: JPopupMenu

Notifies PopupMenuListeners that this popup menu will become invisible.

Overrides:

firePopupMenuWillBecomeInvisible in class JPopupMenu

firePopupMenuCanceled

protected void firePopupMenuCanceled()

Description copied from class: JPopupMenu

Notifies PopupMenuListeners that this popup menu is cancelled.

Overrides:

firePopupMenuCanceled in class JPopupMenu

createMouseListener

protected MouseListener createMouseListener()

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.

Returns:

a MouseListener which will be added to the combo box or null

createMouseMotionListener

protected MouseMotionListener createMouseMotionListener()

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.

Returns:

a MouseMotionListener which will be added to the combo box or null

createKeyListener

protected KeyListener createKeyListener()

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.

Returns:

a KeyListener or null

createListSelectionListener

protected ListSelectionListener createListSelectionListener()

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.

Returns:

an instance of a ListSelectionListener or null

createListDataListener

protected ListDataListener createListDataListener()

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.

Returns:

an instance of a ListDataListener or null

createListMouseListener

protected MouseListener createListMouseListener()

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.

Returns:

an instance of a MouseListener or null

createListMouseMotionListener

protected MouseMotionListener createListMouseMotionListener()

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.

Returns:

an instance of a MouseMotionListener or null

createPropertyChangeListener

protected PropertyChangeListener createPropertyChangeListener()

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.

Returns:

an instance of a PropertyChangeListener or null

createItemListener

protected ItemListener createItemListener()

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.

Returns:

an instance of an ItemListener or null

createList

protected JList createList()

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.

Returns:

a JList used to display the combo box items

configureList

protected void configureList()

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 Also:

createList()

installListListeners

protected void installListListeners()

Adds the listeners to the list control.

createScroller

protected JScrollPane createScroller()

Creates the scroll pane which houses the scrollable list.

configureScroller

protected void configureScroller()

Configures the scrollable portion which holds the list within the combo box popup. This method is called when the UI class is created.

configurePopup

protected void configurePopup()

Configures the popup portion of the combo box. This method is called when the UI class is created.

installComboBoxListeners

protected void installComboBoxListeners()

This method adds the necessary listeners to the JComboBox.

installComboBoxModelListeners

protected void installComboBoxModelListeners(ComboBoxModel model)

Installs the listeners on the combo box model. Any listeners installed on the combo box model should be removed in uninstallComboBoxModelListeners.

Parameters:

model - The combo box model to install listeners

See Also:

uninstallComboBoxModelListeners(javax.swing.ComboBoxModel)

installKeyboardActions

protected void installKeyboardActions()

isFocusTraversable

public boolean isFocusTraversable()

Overridden to unconditionally return false.

Overrides:

isFocusTraversable in class Component

Returns:

true if this Component is focusable; false otherwise

See Also:

Component.setFocusable(boolean)

startAutoScrolling

protected void startAutoScrolling(int direction)

This protected method is implementation specific and should be private. do not call or override.

stopAutoScrolling

protected void stopAutoScrolling()

This protected method is implementation specific and should be private. do not call or override.

autoScrollUp

protected void autoScrollUp()

This protected method is implementation specific and should be private. do not call or override.

autoScrollDown

protected void autoScrollDown()

This protected method is implementation specific and should be private. do not call or override.

getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this BasicComboPopup. The AccessibleContext will have its parent set to the ComboBox.

Specified by:

getAccessibleContext in interface Accessible

Overrides:

getAccessibleContext in class JPopupMenu

Returns:

an AccessibleContext for the BasicComboPopup

Since:

1.5

delegateFocus

protected void delegateFocus(MouseEvent e)

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.

togglePopup

protected void togglePopup()

Makes the popup visible if it is hidden and makes it hidden if it is visible.

convertMouseEvent

protected MouseEvent convertMouseEvent(MouseEvent e)

getPopupHeightForRowCount

protected int getPopupHeightForRowCount(int maxRowCount)

Retrieves the height of the popup based on the current ListCellRenderer and the maximum row count.

computePopupBounds

protected Rectangle computePopupBounds(int px,
                                       int py,
                                       int pw,
                                       int ph)

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.

Parameters:

px - starting x location

py - starting y location

pw - starting width

ph - starting height

Returns:

a rectangle which represents the placement and size of the popup

updateListBoxSelectionForEvent

protected void updateListBoxSelectionForEvent(MouseEvent anEvent,
                                              boolean shouldScroll)

A utility method used by the event listeners. Given a mouse event, it changes the list selection to the list item below the mouse.