javax.swing
Class JScrollPane.ScrollBar

java.lang.Object
  extended byjava.awt.Component
      extended byjava.awt.Container
          extended byjavax.swing.JComponent
              extended byjavax.swing.JScrollBar
                  extended byjavax.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 JavaBeansTM 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:

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)