Class JScrollPane.ScrollBar

java.lang.Object

java.awt.Component

java.awt.Container

javax.swing.JComponent

javax.swing.JScrollBar

javax.swing.JScrollPane.ScrollBar

All Implemented Interfaces:

Adjustable, ImageObserver, MenuContainer, Serializable, Accessible, UIResource

Enclosing class:

JScrollPane

protected class JScrollPane.ScrollBar
extends JScrollBar
implements UIResource

By default JScrollPane creates scrollbars that are instances of this class. Scrollbar overrides the getUnitIncrement and getBlockIncrement methods so that, if the viewport's view is a Scrollable, the view is asked to compute these values. Unless the unit/block increment have been explicitly set.

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

Since:

1.2

See Also:

• Scrollable
• JScrollPane.createVerticalScrollBar()
• JScrollPane.createHorizontalScrollBar()

Nested Class Summary

Nested classes/interfaces declared in class javax.swing.JScrollBar

JScrollBar.AccessibleJScrollBar

Nested classes/interfaces declared in class javax.swing.JComponent

JComponent.AccessibleJComponent

Nested classes/interfaces declared in class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces declared in class java.awt.Component

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

Field Summary

Fields declared in class javax.swing.JScrollBar

blockIncrement, model, orientation, unitIncrement

Fields declared in class javax.swing.JComponent

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

Fields declared in class java.awt.Component

accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields declared in interface java.awt.Adjustable

HORIZONTAL, NO_ORIENTATION, VERTICAL

Fields declared in interface java.awt.image.ImageObserver

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

Constructor Summary

Constructors

Constructor	Description
ScrollBar(int orientation)	Creates a scrollbar with the specified orientation.

Method Summary

Modifier and Type	Method	Description
int	getBlockIncrement(int direction)	Computes the block increment for scrolling if the viewport's view is a Scrollable object.
int	getUnitIncrement(int direction)	Computes the unit increment for scrolling if the viewport's view is a Scrollable object.
void	setBlockIncrement(int blockIncrement)	Messages super to set the value, and resets the blockIncrementSet instance variable to true.
void	setUnitIncrement(int unitIncrement)	Messages super to set the value, and resets the unitIncrementSet instance variable to true.

Methods declared in class javax.swing.JScrollBar

addAdjustmentListener, fireAdjustmentValueChanged, getAccessibleContext, getAdjustmentListeners, getBlockIncrement, getMaximum, getMaximumSize, getMinimum, getMinimumSize, getModel, getOrientation, getUI, getUIClassID, getUnitIncrement, getValue, getValueIsAdjusting, getVisibleAmount, paramString, removeAdjustmentListener, setEnabled, setMaximum, setMaximumSize, setMinimum, setMinimumSize, setModel, setOrientation, setUI, setValue, setValueIsAdjusting, setValues, setVisibleAmount, updateUI

Methods declared in class javax.swing.JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, 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, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, 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, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update

Methods declared in 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, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree

Methods declared in 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, 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, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setMixingCutoutShape, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods declared in class java.lang.Object

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

Constructor Details

ScrollBar

public ScrollBar(int orientation)

Creates a scrollbar with the specified orientation. The options are:

• ScrollPaneConstants.VERTICAL
• ScrollPaneConstants.HORIZONTAL

Parameters:

orientation - an integer specifying one of the legal orientation values shown above

Since:

1.4

Method Details

setUnitIncrement

public void setUnitIncrement(int unitIncrement)

Messages super to set the value, and resets the unitIncrementSet instance variable to true.

Specified by:

setUnitIncrement in interface Adjustable

Overrides:

setUnitIncrement in class JScrollBar

Parameters:

unitIncrement - the new unit increment value, in pixels

See Also:

• JScrollBar.getUnitIncrement(int)

getUnitIncrement

public int getUnitIncrement(int direction)

Computes the unit increment for scrolling if the viewport's view is a Scrollable object. Otherwise return super.getUnitIncrement.

Overrides:

getUnitIncrement in class JScrollBar

Parameters:

direction - less than zero to scroll up/left, greater than zero for down/right

Returns:

an integer, in pixels, containing the unit increment

See Also:

• Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)

setBlockIncrement

public void setBlockIncrement(int blockIncrement)

Messages super to set the value, and resets the blockIncrementSet instance variable to true.

Specified by:

setBlockIncrement in interface Adjustable

Overrides:

setBlockIncrement in class JScrollBar

Parameters:

blockIncrement - the new block increment value, in pixels

See Also:

• JScrollBar.getBlockIncrement()

getBlockIncrement

public int getBlockIncrement(int direction)

Computes the block increment for scrolling if the viewport's view is a Scrollable object. Otherwise the blockIncrement equals the viewport's width or height. If there's no viewport return super.getBlockIncrement.

Overrides:

getBlockIncrement in class JScrollBar

Parameters:

direction - less than zero to scroll up/left, greater than zero for down/right

Returns:

an integer, in pixels, containing the block increment

See Also:

• Scrollable.getScrollableBlockIncrement(java.awt.Rectangle, int, int)