javax.swing.plaf.basic
Class BasicComboBoxUI

java.lang.Object
  |
  +--javax.swing.plaf.ComponentUI
        |
        +--javax.swing.plaf.ComboBoxUI
              |
              +--javax.swing.plaf.basic.BasicComboBoxUI

Direct Known Subclasses:

MetalComboBoxUI

public class BasicComboBoxUI

extends ComboBoxUI

Basic UI for JComboBox. This class adds and removes components from the JComboBox. The arrow button and the editor are managed by this object. The popup menu is handled by BasicComboPopup. BasicComboPopup supplies this class with a MouseListener, MouseMotionListener, and a KeyListener. These listeners are added to the arrow button and the JComboBox by default. Subclasses of BasicComboBoxUI should attach the listeners to whichever components they like. installListeners() is where listeners get added to the JComboBox (and model). configureEditor() is where listeners get added to the editor. configureArrowButton() is where listeners get added to the arrow button. Inner classes for handling events: FocusHandler ItemHandler ListDataHandler PropertyChangeHandler KeyHandler

Inner Class Summary

class	BasicComboBoxUI.ComboBoxLayoutManager This layout manager handles the 'standard' layout of combo boxes.
class	BasicComboBoxUI.FocusHandler This listener hides the popup when the focus is lost.
class	BasicComboBoxUI.ItemHandler This listener watches for changes to the selection in the combo box and updates the display of the currently selected item.
class	BasicComboBoxUI.KeyHandler This listener checks to see if the key event isn't a navigation key.
class	BasicComboBoxUI.ListDataHandler This listener watches for changes in the data and revalidates.
class	BasicComboBoxUI.PropertyChangeHandler This listener watches for bound properties that have changed in the JComboBox.

Field Summary

protected JButton	arrowButton
protected Dimension	cachedMinimumSize
protected JComboBox	comboBox
protected CellRendererPane	currentValuePane
protected Component	editor
protected FocusListener	focusListener
protected boolean	hasFocus
protected boolean	isMinimumSizeDirty
protected ItemListener	itemListener
protected KeyListener	keyListener
protected JList	listBox
protected ListDataListener	listDataListener
protected ComboPopup	popup
protected KeyListener	popupKeyListener
protected MouseListener	popupMouseListener
protected MouseMotionListener	popupMouseMotionListener
protected PropertyChangeListener	propertyChangeListener

Constructor Summary

BasicComboBoxUI()

Method Summary

void	addEditor() Adds the editor to the JComboBox.
void	configureArrowButton() Configures the arrow button by adding listeners.
protected void	configureEditor() Configures the editor by setting its font and adding listeners.
protected JButton	createArrowButton() Creates the arrow button.
protected ComboBoxEditor	createEditor() Creates the editor that is to be used in editable combo boxes.
protected FocusListener	createFocusListener() Creates the focus listener that hides the popup when the focus is lost.
protected ItemListener	createItemListener() Creates the item listener that watches for updates in the current selection so that it can update the display.
protected KeyListener	createKeyListener() Creates the key listener for handling type-ahead.
protected LayoutManager	createLayoutManager() Creates the standard combo box layout manager that has the arrow button to the right and the editor to the left.
protected ListDataListener	createListDataListener() Creates the list data listener that is used for caching the preferred sizes.
protected ComboPopup	createPopup() Creates an implementation of the ComboPopup interface.
protected PropertyChangeListener	createPropertyChangeListener() Creates the list data listener that is used for caching the preferred sizes.
protected ListCellRenderer	createRenderer() Creates the renderer that is to be used in the combo box.
static ComponentUI	createUI(JComponent c)
Accessible	getAccessibleChild(JComponent c, int i) Return the nth Accessible child of the object.
int	getAccessibleChildrenCount(JComponent c) Returns the number of accessible children in the object.
protected Dimension	getDefaultSize() Return the default size of an empty combo box.
protected Dimension	getDisplaySize()
protected Insets	getInsets() Gets the insets from the JComboBox.
Dimension	getMaximumSize(JComponent c)
Dimension	getMinimumSize(JComponent c)
Dimension	getPreferredSize(JComponent c)
protected void	installComponents() The editor and arrow button are added to the JComboBox here.
protected void	installDefaults() Installs the default colors, default font, default renderer, and default editor into the JComboBox.
protected void	installKeyboardActions() Adds keyboard actions to the JComboBox.
protected void	installListeners() Attaches listeners to the JComboBox and JComboBoxModel.
void	installUI(JComponent c)
boolean	isFocusTraversable(JComboBox c) Determines if the JComboBox is focus traversable.
protected boolean	isNavigationKey(int keyCode) Returns whether or not the supplied keyCode maps to a key that is used for navigation.
boolean	isPopupVisible(JComboBox c) Tells if the popup is visible or not.
void	paint(Graphics g, JComponent c)
void	paintCurrentValue(Graphics g, Rectangle bounds, boolean hasFocus) Paints the currently selected item.
void	paintCurrentValueBackground(Graphics g, Rectangle bounds, boolean hasFocus) Paints the background of the currently selected item.
protected Rectangle	rectangleForCurrentValue() Returns the area that is reserved for drawing the currently selected item.
void	removeEditor() Removes the editor from the JComboBox.
protected void	selectNextPossibleValue() Selects the next item in the list.
protected void	selectPreviousPossibleValue() Selects the previous item in the list.
void	setPopupVisible(JComboBox c, boolean v) Hides the popup.
protected void	toggleOpenClose() Hides the popup if it is showing and shows the popup if it is hidden.
void	unconfigureArrowButton() Unconfigures the arrow button by removing listeners.
protected void	unconfigureEditor() Unconfigures the editor by removing listeners.
protected void	uninstallComponents() The editor and/or arrow button are removed from the JComboBox here.
protected void	uninstallDefaults() Uninstalls the default colors, default font, default renderer, and default editor into the JComboBox.
protected void	uninstallKeyboardActions() Removes the focus InputMap and ActionMap.
protected void	uninstallListeners() Removes listeners from the JComboBox and JComboBoxModel.
void	uninstallUI(JComponent c)

Methods inherited from class javax.swing.plaf.ComponentUI

contains, update

Methods inherited from class java.lang.Object

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

Field Detail

comboBox

protected JComboBox comboBox

hasFocus

protected boolean hasFocus

listBox

protected JList listBox

currentValuePane

protected CellRendererPane currentValuePane

popup

protected ComboPopup popup

editor

protected Component editor

arrowButton

protected JButton arrowButton

keyListener

protected KeyListener keyListener

focusListener

protected FocusListener focusListener

itemListener

protected ItemListener itemListener

propertyChangeListener

protected PropertyChangeListener propertyChangeListener

popupMouseListener

protected MouseListener popupMouseListener

popupMouseMotionListener

protected MouseMotionListener popupMouseMotionListener

popupKeyListener

protected KeyListener popupKeyListener

listDataListener

protected ListDataListener listDataListener

isMinimumSizeDirty

protected boolean isMinimumSizeDirty

cachedMinimumSize

protected Dimension cachedMinimumSize

Constructor Detail

BasicComboBoxUI

public BasicComboBoxUI()

Method Detail

createUI

public static ComponentUI createUI(JComponent c)

installUI

public void installUI(JComponent c)

Overrides:

installUI in class ComponentUI

uninstallUI

public void uninstallUI(JComponent c)

Overrides:

uninstallUI in class ComponentUI

installDefaults

protected void installDefaults()

Installs the default colors, default font, default renderer, and default editor into the JComboBox.

installListeners

protected void installListeners()

Attaches listeners to the JComboBox and JComboBoxModel.

uninstallDefaults

protected void uninstallDefaults()

Uninstalls the default colors, default font, default renderer, and default editor into the JComboBox.

uninstallListeners

protected void uninstallListeners()

Removes listeners from the JComboBox and JComboBoxModel.

createPopup

protected ComboPopup createPopup()

Creates an implementation of the ComboPopup interface. Returns an instance of BasicComboPopup.

createKeyListener

protected KeyListener createKeyListener()

Creates the key listener for handling type-ahead. Returns an instance of BasicComboBoxUI$KeyHandler.

createFocusListener

protected FocusListener createFocusListener()

Creates the focus listener that hides the popup when the focus is lost. Returns an instance of BasicComboBoxUI$FocusHandler.

createListDataListener

protected ListDataListener createListDataListener()

Creates the list data listener that is used for caching the preferred sizes. Returns an instance of BasicComboBoxUI$ListDataHandler.

createItemListener

protected ItemListener createItemListener()

Creates the item listener that watches for updates in the current selection so that it can update the display. Returns an instance of BasicComboBoxUI$ItemHandler.

createPropertyChangeListener

protected PropertyChangeListener createPropertyChangeListener()

Creates the list data listener that is used for caching the preferred sizes. Returns an instance of BasicComboBoxUI$PropertyChangeHandler.

createLayoutManager

protected LayoutManager createLayoutManager()

Creates the standard combo box layout manager that has the arrow button to the right and the editor to the left. Returns an instance of BasicComboBoxUI$ComboBoxLayoutManager.

createRenderer

protected ListCellRenderer createRenderer()

Creates the renderer that is to be used in the combo box. This method only gets called if a custom renderer has nto already been installed in the JComboBox.

createEditor

protected ComboBoxEditor createEditor()

Creates the editor that is to be used in editable combo boxes. This method only gets called if a custom editor has not already been installed in the JComboBox.

installComponents

protected void installComponents()

The editor and arrow button are added to the JComboBox here.

uninstallComponents

protected void uninstallComponents()

The editor and/or arrow button are removed from the JComboBox here. This method calls removeAll() on the JComboBox just to make sure that everything gets removed.

addEditor

public void addEditor()

Adds the editor to the JComboBox.

removeEditor

public void removeEditor()

Removes the editor from the JComboBox. It also calls unconfigureEditor()

configureEditor

protected void configureEditor()

Configures the editor by setting its font and adding listeners.

unconfigureEditor

protected void unconfigureEditor()

Unconfigures the editor by removing listeners.

configureArrowButton

public void configureArrowButton()

Configures the arrow button by adding listeners.

unconfigureArrowButton

public void unconfigureArrowButton()

Unconfigures the arrow button by removing listeners.

createArrowButton

protected JButton createArrowButton()

Creates the arrow button. Subclasses can create any button they like. The default behavior of this class is to attach various listeners to the button returned by this method. Returns an instance of BasicArrowButton.

isPopupVisible

public boolean isPopupVisible(JComboBox c)

Tells if the popup is visible or not.

Overrides:

isPopupVisible in class ComboBoxUI

setPopupVisible

public void setPopupVisible(JComboBox c,
                            boolean v)

Hides the popup.

Overrides:

setPopupVisible in class ComboBoxUI

isFocusTraversable

public boolean isFocusTraversable(JComboBox c)

Determines if the JComboBox is focus traversable. If the JComboBox is editable this returns false, otherwise it returns true.

Overrides:

isFocusTraversable in class ComboBoxUI

paint

public void paint(Graphics g,
                  JComponent c)

Overrides:

paint in class ComponentUI

getPreferredSize

public Dimension getPreferredSize(JComponent c)

Overrides:

getPreferredSize in class ComponentUI

getMinimumSize

public Dimension getMinimumSize(JComponent c)

Overrides:

getMinimumSize in class ComponentUI

getMaximumSize

public Dimension getMaximumSize(JComponent c)

Overrides:

getMaximumSize in class ComponentUI

getAccessibleChildrenCount

public int getAccessibleChildrenCount(JComponent c)

Description copied from class: ComponentUI

Returns the number of accessible children in the object. If all of the children of this object implement Accessible, than this method should return the number of children of this object. UI's might wish to override this if they present areas on the screen that can be viewed as components, but actual components are not used for presenting those areas. Note: as of the Java 2 platform v1.3, it is recommended that developers call Component.AccessibleAWTComponent.getAccessibleChildrenCount() instead of using this method.

Overrides:

getAccessibleChildrenCount in class ComponentUI

Following copied from class: javax.swing.plaf.ComponentUI

Returns:

the number of accessible children in the object.

See Also:

ComponentUI.getAccessibleChild(javax.swing.JComponent, int)

getAccessibleChild

public Accessible getAccessibleChild(JComponent c,
                                     int i)

Description copied from class: ComponentUI

Return the nth Accessible child of the object. UI's might wish to override this if they present areas on the screen that can be viewed as components, but actual components are not used for presenting those areas. Note: as of the Java 2 platform v1.3, it is recommended that developers call Component.AccessibleAWTComponent.getAccessibleChild() instead of using this method.

Overrides:

getAccessibleChild in class ComponentUI

Following copied from class: javax.swing.plaf.ComponentUI

Parameters:

i - zero-based index of child

Returns:

the nth Accessible child of the object

See Also:

ComponentUI.getAccessibleChildrenCount(javax.swing.JComponent)

isNavigationKey

protected boolean isNavigationKey(int keyCode)

Returns whether or not the supplied keyCode maps to a key that is used for navigation. This is used for optimizing key input by only passing non- navigation keys to the type-ahead mechanism. Subclasses should override this if they change the navigation keys.

selectNextPossibleValue

protected void selectNextPossibleValue()

Selects the next item in the list. It won't change the selection if the currently selected item is already the last item.

selectPreviousPossibleValue

protected void selectPreviousPossibleValue()

Selects the previous item in the list. It won't change the selection if the currently selected item is already the first item.

toggleOpenClose

protected void toggleOpenClose()

Hides the popup if it is showing and shows the popup if it is hidden.

rectangleForCurrentValue

protected Rectangle rectangleForCurrentValue()

Returns the area that is reserved for drawing the currently selected item.

getInsets

protected Insets getInsets()

Gets the insets from the JComboBox.

paintCurrentValue

public void paintCurrentValue(Graphics g,
                              Rectangle bounds,
                              boolean hasFocus)

Paints the currently selected item.

paintCurrentValueBackground

public void paintCurrentValueBackground(Graphics g,
                                        Rectangle bounds,
                                        boolean hasFocus)

Paints the background of the currently selected item.

getDefaultSize

protected Dimension getDefaultSize()

Return the default size of an empty combo box.

getDisplaySize

protected Dimension getDisplaySize()

installKeyboardActions

protected void installKeyboardActions()

Adds keyboard actions to the JComboBox. Actions on enter and esc are already supplied. Add more actions as you need them.

uninstallKeyboardActions

protected void uninstallKeyboardActions()

Removes the focus InputMap and ActionMap.