javax.swing
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:

javax.accessibility.Accessible, Adjustable, ImageObserver, MenuContainer, Serializable, 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^TM has been added to the java.beans package. Please see XMLEncoder.

See Also:

Scrollable, JScrollPane.createVerticalScrollBar(), JScrollPane.createHorizontalScrollBar(), Serialized Form

Nested Class Summary

Nested classes inherited from class javax.swing.JScrollBar

JScrollBar.AccessibleJScrollBar

Nested classes inherited from class javax.swing.JComponent

JComponent.AccessibleJComponent, JComponent.ActionStandin, JComponent.IntVector, JComponent.KeyboardState

Nested classes inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes inherited from class java.awt.Component

Component.AccessibleAWTComponent, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

private boolean	blockIncrementSet Set to true when the block increment has been explicitly set.
private boolean	unitIncrementSet Set to true when the unit increment has been explicitly set.

Fields inherited from class javax.swing.JScrollBar

blockIncrement, model, orientation, unitIncrement

Fields inherited from class javax.swing.JComponent

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

Fields inherited from class java.awt.Container

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.Adjustable

HORIZONTAL, NO_ORIENTATION, VERTICAL

Fields inherited from interface java.awt.image.ImageObserver

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

Constructor Summary

JScrollPane.ScrollBar(int orientation)
Creates a scrollbar with the specified orientation, where the options are: JScrollPane.VERTICAL JScrollPane.HORIZONTAL

Method Summary

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 inherited from 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, setMinimum, setModel, setOrientation, setUI, setValue, setValueIsAdjusting, setValues, setVisibleAmount, updateUI

Methods inherited from class javax.swing.JComponent

_paintImmediately, addAncestorListener, addNotify, addPropertyChangeListener, addPropertyChangeListener, addVetoableChangeListener, alwaysOnTop, checkIfChildObscuredBySibling, componentInputMapChanged, computeVisibleRect, computeVisibleRect, compWriteObjectNotify, contains, createToolTip, disable, enable, enableSerialization, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBorder, getBounds, getClientProperty, getComponentGraphics, getConditionForKeyStroke, getCreatedDoubleBuffer, getDebugGraphicsOptions, getDefaultLocale, getGraphics, getHeight, getInputMap, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getManagingFocusBackwardTraversalKeys, getManagingFocusForwardTraversalKeys, getNextFocusableComponent, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getWriteObjCounter, getX, getY, grabFocus, isDoubleBuffered, isLightweightComponent, isManagingFocus, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isOptimizedDrawingEnabled, isPaintingOrigin, isPaintingTile, isPreferredSizeSet, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyBindings, processKeyBindingsForAllComponents, processKeyEvent, processMouseMotionEvent, putClientProperty, rectangleIsObscured, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setCreatedDoubleBuffer, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setFont, setForeground, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPaintingChild, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, setWriteObjCounter, shouldDebugGraphics, superProcessMouseMotionEvent, unregisterKeyboardAction, update

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setFocusCycleRoot, setFocusTraversalKeys, setFocusTraversalPolicy, 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, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMouseWheelListeners, getName, getParent, getPeer, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, 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, processMouseEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusUpCycle

Methods inherited from class java.lang.Object

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

Field Detail

unitIncrementSet

private boolean unitIncrementSet

Set to true when the unit increment has been explicitly set. If this is false the viewport's view is obtained and if it is an instance of Scrollable the unit increment from it is used.

blockIncrementSet

private boolean blockIncrementSet

Set to true when the block increment has been explicitly set. If this is false the viewport's view is obtained and if it is an instance of Scrollable the block increment from it is used.

Constructor Detail

JScrollPane.ScrollBar

public JScrollPane.ScrollBar(int orientation)

Creates a scrollbar with the specified orientation, where the options are:

• JScrollPane.VERTICAL
• JScrollPane.HORIZONTAL

Parameters:

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

Method Detail

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)