OpenJDK 27 · javax.swing.plaf.basic.BasicScrollBarUI

Modifier and Type	Class and Description
private static class	BasicScrollBarUI.Actions Used for scrolling the scrollbar.
protected class	BasicScrollBarUI.ArrowButtonListener Listener for cursor keys.
private class	BasicScrollBarUI.Handler
protected class	BasicScrollBarUI.ModelListener A listener to listen for model changes.
public class	BasicScrollBarUI.PropertyChangeHandler Property change handler
protected class	BasicScrollBarUI.ScrollListener Listener for scrolling events initiated in the `ScrollPane`.
protected class	BasicScrollBarUI.TrackListener Track mouse drags.

Field Summary

Modifier and Type	Field and Description
protected BasicScrollBarUI.ArrowButtonListener	buttonListener Button listener
protected JButton	decrButton Decrement button
protected static final int	DECREASE_HIGHLIGHT Decrease highlight
protected int	decrGap Distance between the decrement button and the track.
private BasicScrollBarUI.Handler	handler
protected JButton	incrButton Increment button
protected static final int	INCREASE_HIGHLIGHT Increase highlight
protected int	incrGap Distance between the increment button and the track.
protected boolean	isDragging Dragging
private static final int	MAX_SCROLL
protected Dimension	maximumThumbSize Maximum thumb size
private static final int	MIN_SCROLL
protected Dimension	minimumThumbSize Minimum thumb size
protected BasicScrollBarUI.ModelListener	modelListener Model listener
private static final int	NEGATIVE_SCROLL
protected static final int	NO_HIGHLIGHT No highlight
private static final int	POSITIVE_SCROLL
protected PropertyChangeListener	propertyChangeListener Property change listener
protected JScrollBar	scrollbar Scrollbar
private int	scrollBarValue The scrollbar value is cached to save real value if the view is adjusted.
protected int	scrollBarWidth Hint as to what width (when vertical) or height (when horizontal) should be.
protected BasicScrollBarUI.ScrollListener	scrollListener Scroll listener
private static final int	scrollSpeedThrottle
protected Timer	scrollTimer Scroll timer
private boolean	supportsAbsolutePositioning True indicates a middle click will absolutely position the scrollbar.
private boolean	thumbActive
protected Color	thumbColor Thumb color
protected Color	thumbDarkShadowColor Thumb dark shadow color
protected Color	thumbHighlightColor Thumb highlight color
protected Color	thumbLightShadowColor Thumb light shadow color
protected Rectangle	thumbRect Thumb rectangle
protected Color	trackColor Track color
protected int	trackHighlight Track highlight
protected Color	trackHighlightColor Track highlight color
protected BasicScrollBarUI.TrackListener	trackListener Track listener
protected Rectangle	trackRect Track rectangle
private boolean	useCachedValue Determine whether scrollbar layout should use cached value or adjusted value returned by scrollbar's `getValue`.

Access	Constructor and Description
public	BasicScrollBarUI() Constructs a `BasicScrollBarUI`.

Method Summary

Modifier and Type	Method and Description
public void	addLayoutComponent(String name, Component child) Implements java.awt.LayoutManager.addLayoutComponent. If the layout manager uses a per-component string, adds the component `comp` to the layout, associating it with the string specified by `name`.
protected void	configureScrollBarColors() Configures the scroll bar colors.
protected BasicScrollBarUI.ArrowButtonListener	Returns: an arrow button listener createArrowButtonListener() Creates an arrow button listener.
protected JButton	Returns: a decrease button createDecreaseButton(int the orientation orientation) Creates a decrease button.
protected JButton	Returns: an increase button createIncreaseButton(int the orientation orientation) Creates an increase button.
protected BasicScrollBarUI.ModelListener	Returns: a model listener createModelListener() Creates a model listener.
protected PropertyChangeListener	Returns: a property change listener createPropertyChangeListener() Creates a property change listener.
protected BasicScrollBarUI.ScrollListener	Returns: a scroll listener createScrollListener() Creates a scroll listener.
protected BasicScrollBarUI.TrackListener	Returns: a track listener createTrackListener() Creates a track listener.
public static ComponentUI	Returns: the UI createUI(JComponent the component c) Hides javax.swing.plaf.ComponentUI.createUI. Creates the UI.
private BasicScrollBarUI.Handler	getHandler()
private InputMap	getInputMap(int condition)
public Dimension	Returns: new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE); getMaximumSize(JComponent The JScrollBar that's delegating this method to us. c) Overrides javax.swing.plaf.ComponentUI.getMaximumSize. Returns the specified component's maximum size appropriate for the look and feel.
protected Dimension	Returns: The largest acceptable size for the thumb. getMaximumThumbSize() Returns the largest acceptable size for the thumb.
protected Dimension	Returns: The smallest acceptable size for the thumb. getMinimumThumbSize() Returns the smallest acceptable size for the thumb.
public Dimension	Returns: the preferred size of a Basic JScrollBar getPreferredSize(JComponent the `JScrollBar` that's delegating this method to us c) Overrides javax.swing.plaf.ComponentUI.getPreferredSize. A vertical scrollbar's preferred width is the maximum of preferred widths of the (non `null`) increment/decrement buttons, and the minimum width of the thumb.
public boolean	Returns: true if a mouse gesture can absolutely position the thumb getSupportsAbsolutePositioning() Indicates whether the user can absolutely position the thumb with a mouse gesture (usually the middle mouse button).
protected Rectangle	Returns: The current size/location of the thumb. getThumbBounds() Return the current size/location of the thumb.
protected Rectangle	Returns: the current bounds of the scrollbar track getTrackBounds() Returns the current bounds of the track, i.e. the space in between the increment and decrement buttons, less the insets.
private int	getValue(JScrollBar sb)
protected void	installComponents() Installs the components.
protected void	installDefaults() Installs the defaults.
protected void	installKeyboardActions() Installs the keyboard actions.
protected void	installListeners() Installs the listeners.
public void	installUI(JComponent the component c) Overrides javax.swing.plaf.ComponentUI.installUI. Installs the UI.
private boolean	isMouseAfterThumb()
private boolean	isMouseBeforeThumb()
private boolean	isMouseLeftOfThumb()
private boolean	isMouseRightOfThumb()
public boolean	Returns: true if the thumb is currently active isThumbRollover() Returns true if the mouse is currently over the thumb.
public void	layoutContainer(Container scrollbarContainer) Implements java.awt.LayoutManager.layoutContainer. Lays out the specified container.
protected void	layoutHScrollbar(JScrollBar the scroll bar sb) Lays out a horizontal scroll bar.
protected void	layoutVScrollbar(JScrollBar the scroll bar sb) Lays out a vertical scroll bar.
pack-priv static void	loadActionMap(LazyActionMap map)
public Dimension	minimumLayoutSize(Container scrollbarContainer) Implements java.awt.LayoutManager.minimumLayoutSize. Calculates the minimum size dimensions for the specified container, given the components it contains.
public void	paint(Graphics g, JComponent c) Overrides javax.swing.plaf.ComponentUI.paint. Paints the specified component appropriately for the look and feel.
protected void	paintDecreaseHighlight(Graphics the graphics g) Paints the decrease highlight.
protected void	paintIncreaseHighlight(Graphics the graphics g) Paints the increase highlight.
protected void	paintThumb(Graphics the graphics g, JComponent the component c, Rectangle the thumb bounds thumbBounds) Paints the thumb.
protected void	paintTrack(Graphics the graphics g, JComponent the component c, Rectangle the track bounds trackBounds) Paints the track.
public Dimension	preferredLayoutSize(Container scrollbarContainer) Implements java.awt.LayoutManager.preferredLayoutSize. Calculates the preferred size dimensions for the specified container, given the components it contains.
public void	removeLayoutComponent(Component child) Implements java.awt.LayoutManager.removeLayoutComponent. Removes the specified component from the layout.
pack-priv static void	scrollByBlock(JScrollBar scrollbar, int direction)
protected void	scrollByBlock(int the direction to scroll direction) Scrolls by block.
protected void	scrollByUnit(int the direction to scroll direction) Scrolls by unit.
pack-priv static void	scrollByUnits(JScrollBar scrollbar, int direction, int units, boolean limitToBlock)
private void	setDragging(boolean dragging)
protected void	setThumbBounds(int set the x location of the thumb x, int set the y location of the thumb y, int set the width of the thumb width, int set the height of the thumb height) Set the bounds of the thumb and force a repaint that includes the old thumbBounds and the new one.
protected void	setThumbRollover(boolean True indicates the thumb is currently active. active) Sets whether or not the mouse is currently over the thumb.
private void	stopScrollTimer(ActionEvent e)
protected void	uninstallComponents() Uninstalls the components.
protected void	uninstallDefaults() Uninstalls the defaults.
protected void	uninstallKeyboardActions() Uninstalls the keyboard actions.
protected void	uninstallListeners() Uninstall the listeners.
public void	uninstallUI(JComponent the component c) Overrides javax.swing.plaf.ComponentUI.uninstallUI. Uninstalls the UI.
private void	updateButtonDirections()
private void	updateThumbState(int x, int y)

public Class BasicScrollBarUI

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary