Adjustable
, ImageObserver
, MenuContainer
, Serializable
, Accessible
public class Scrollbar extends Component implements Adjustable, Accessible
Scrollbar
class embodies a scroll bar, a
familiar user-interface object. A scroll bar provides a
convenient means for allowing a user to select from a
range of values. The following three vertical
scroll bars could be used as slider controls to pick
the red, green, and blue components of a color:
Each scroll bar in this example could be created with code similar to the following:
redSlider=new Scrollbar(Scrollbar.VERTICAL, 0, 1, 0, 255); add(redSlider);
Alternatively, a scroll bar can represent a range of values. For example, if a scroll bar is used for scrolling through text, the width of the "bubble" (also called the "thumb" or "scroll box") can be used to represent the amount of text that is visible. Here is an example of a scroll bar that represents a range:
The value range represented by the bubble in this example is the visible amount. The horizontal scroll bar in this example could be created with code like the following:
ranger = new Scrollbar(Scrollbar.HORIZONTAL, 0, 60, 0, 300); add(ranger);
Note that the actual maximum value of the scroll bar is the
maximum
minus the visible amount
.
In the previous example, because the maximum
is
300 and the visible amount
is 60, the actual maximum
value is 240. The range of the scrollbar track is 0 - 300.
The left side of the bubble indicates the value of the
scroll bar.
Normally, the user changes the value of the scroll bar by making a gesture with the mouse. For example, the user can drag the scroll bar's bubble up and down, or click in the scroll bar's unit increment or block increment areas. Keyboard gestures can also be mapped to the scroll bar. By convention, the Page Up and Page Down keys are equivalent to clicking in the scroll bar's block increment and block decrement areas.
When the user changes the value of the scroll bar, the scroll bar
receives an instance of AdjustmentEvent
.
The scroll bar processes this event, passing it along to
any registered listeners.
Any object that wishes to be notified of changes to the
scroll bar's value should implement
AdjustmentListener
, an interface defined in
the package java.awt.event
.
Listeners can be added and removed dynamically by calling
the methods addAdjustmentListener
and
removeAdjustmentListener
.
The AdjustmentEvent
class defines five types
of adjustment event, listed here:
AdjustmentEvent.TRACK
is sent out when the
user drags the scroll bar's bubble.
AdjustmentEvent.UNIT_INCREMENT
is sent out
when the user clicks in the left arrow of a horizontal scroll
bar, or the top arrow of a vertical scroll bar, or makes the
equivalent gesture from the keyboard.
AdjustmentEvent.UNIT_DECREMENT
is sent out
when the user clicks in the right arrow of a horizontal scroll
bar, or the bottom arrow of a vertical scroll bar, or makes the
equivalent gesture from the keyboard.
AdjustmentEvent.BLOCK_INCREMENT
is sent out
when the user clicks in the track, to the left of the bubble
on a horizontal scroll bar, or above the bubble on a vertical
scroll bar. By convention, the Page Up
key is equivalent, if the user is using a keyboard that
defines a Page Up key.
AdjustmentEvent.BLOCK_DECREMENT
is sent out
when the user clicks in the track, to the right of the bubble
on a horizontal scroll bar, or below the bubble on a vertical
scroll bar. By convention, the Page Down
key is equivalent, if the user is using a keyboard that
defines a Page Down key.
The JDK 1.0 event system is supported for backwards compatibility, but its use with newer versions of the platform is discouraged. The five types of adjustment events introduced with JDK 1.1 correspond to the five event types that are associated with scroll bars in previous platform versions. The following list gives the adjustment event type, and the corresponding JDK 1.0 event type it replaces.
AdjustmentEvent.TRACK
replaces
Event.SCROLL_ABSOLUTE
AdjustmentEvent.UNIT_INCREMENT
replaces
Event.SCROLL_LINE_UP
AdjustmentEvent.UNIT_DECREMENT
replaces
Event.SCROLL_LINE_DOWN
AdjustmentEvent.BLOCK_INCREMENT
replaces
Event.SCROLL_PAGE_UP
AdjustmentEvent.BLOCK_DECREMENT
replaces
Event.SCROLL_PAGE_DOWN
Note: We recommend using a Scrollbar
for value selection only. If you want to implement
a scrollable component inside a container, we recommend you use
a ScrollPane
. If you use a
Scrollbar
for this purpose, you are likely to
encounter issues with painting, key handling, sizing and
positioning.
AdjustmentEvent
,
AdjustmentListener
,
Serialized FormModifier and Type | Class | Description |
---|---|---|
protected class |
Scrollbar.AccessibleAWTScrollBar |
This class implements accessibility support for the
Scrollbar class. |
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
Modifier and Type | Field | Description |
---|---|---|
static int |
HORIZONTAL |
A constant that indicates a horizontal scroll bar.
|
static int |
VERTICAL |
A constant that indicates a vertical scroll bar.
|
NO_ORIENTATION
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH
Constructor | Description |
---|---|
Scrollbar() |
Constructs a new vertical scroll bar.
|
Scrollbar(int orientation) |
Constructs a new scroll bar with the specified orientation.
|
Scrollbar(int orientation,
int value,
int visible,
int minimum,
int maximum) |
Constructs a new scroll bar with the specified orientation,
initial value, visible amount, and minimum and maximum values.
|
Modifier and Type | Method | Description |
---|---|---|
void |
addAdjustmentListener(AdjustmentListener l) |
Adds the specified adjustment listener to receive instances of
AdjustmentEvent from this scroll bar. |
void |
addNotify() |
Creates the
Scrollbar 's peer. |
AccessibleContext |
getAccessibleContext() |
Gets the
AccessibleContext associated with this
Scrollbar . |
AdjustmentListener[] |
getAdjustmentListeners() |
Returns an array of all the adjustment listeners
registered on this scrollbar.
|
int |
getBlockIncrement() |
Gets the block increment of this scroll bar.
|
int |
getLineIncrement() |
Deprecated.
As of JDK version 1.1,
replaced by
getUnitIncrement() . |
<T extends EventListener> |
getListeners(Class<T> listenerType) |
Returns an array of all the objects currently registered
as
FooListener s
upon this Scrollbar . |
int |
getMaximum() |
Gets the maximum value of this scroll bar.
|
int |
getMinimum() |
Gets the minimum value of this scroll bar.
|
int |
getOrientation() |
Returns the orientation of this scroll bar.
|
int |
getPageIncrement() |
Deprecated.
As of JDK version 1.1,
replaced by
getBlockIncrement() . |
int |
getUnitIncrement() |
Gets the unit increment for this scrollbar.
|
int |
getValue() |
Gets the current value of this scroll bar.
|
boolean |
getValueIsAdjusting() |
Returns true if the value is in the process of changing as a
result of actions being taken by the user.
|
int |
getVisible() |
Deprecated.
As of JDK version 1.1,
replaced by
getVisibleAmount() . |
int |
getVisibleAmount() |
Gets the visible amount of this scroll bar.
|
protected String |
paramString() |
Returns a string representing the state of this
Scrollbar . |
protected void |
processAdjustmentEvent(AdjustmentEvent e) |
Processes adjustment events occurring on this
scrollbar by dispatching them to any registered
AdjustmentListener objects. |
protected void |
processEvent(AWTEvent e) |
Processes events on this scroll bar.
|
void |
removeAdjustmentListener(AdjustmentListener l) |
Removes the specified adjustment listener so that it no longer
receives instances of
AdjustmentEvent from this scroll bar. |
void |
setBlockIncrement(int v) |
Sets the block increment for this scroll bar.
|
void |
setLineIncrement(int v) |
Deprecated.
As of JDK version 1.1,
replaced by
setUnitIncrement(int) . |
void |
setMaximum(int newMaximum) |
Sets the maximum value of this scroll bar.
|
void |
setMinimum(int newMinimum) |
Sets the minimum value of this scroll bar.
|
void |
setOrientation(int orientation) |
Sets the orientation for this scroll bar.
|
void |
setPageIncrement(int v) |
Deprecated.
As of JDK version 1.1,
replaced by
setBlockIncrement() . |
void |
setUnitIncrement(int v) |
Sets the unit increment for this scroll bar.
|
void |
setValue(int newValue) |
Sets the value of this scroll bar to the specified value.
|
void |
setValueIsAdjusting(boolean b) |
Sets the
valueIsAdjusting property. |
void |
setValues(int value,
int visible,
int minimum,
int maximum) |
Sets the values of four properties for this scroll bar:
value , visibleAmount ,
minimum , and maximum . |
void |
setVisibleAmount(int newAmount) |
Sets the visible amount of this scroll bar.
|
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeys, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusCycleRoot, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, layout, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paint, paintAll, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setMixingCutoutShape, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, update, validate
public static final int HORIZONTAL
public static final int VERTICAL
public Scrollbar() throws HeadlessException
Property | Description | Default Value |
---|---|---|
orientation | indicates whether the scroll bar is vertical
or horizontal |
Scrollbar.VERTICAL |
value | value which controls the location
of the scroll bar's bubble |
0 |
visible amount | visible amount of the scroll bar's range,
typically represented by the size of the scroll bar's bubble |
10 |
minimum | minimum value of the scroll bar | 0 |
maximum | maximum value of the scroll bar | 100 |
unit increment | amount the value changes when the
Line Up or Line Down key is pressed, or when the end arrows of the scrollbar are clicked |
1 |
block increment | amount the value changes when the
Page Up or Page Down key is pressed, or when the scrollbar track is clicked on either side of the bubble |
10 |
HeadlessException
- if GraphicsEnvironment.isHeadless()
returns true.GraphicsEnvironment.isHeadless()
public Scrollbar(int orientation) throws HeadlessException
The orientation
argument must take one of the two
values Scrollbar.HORIZONTAL
,
or Scrollbar.VERTICAL
,
indicating a horizontal or vertical scroll bar, respectively.
orientation
- indicates the orientation of the scroll barIllegalArgumentException
- when an illegal value for
the orientation
argument is suppliedHeadlessException
- if GraphicsEnvironment.isHeadless()
returns true.GraphicsEnvironment.isHeadless()
public Scrollbar(int orientation, int value, int visible, int minimum, int maximum) throws HeadlessException
The orientation
argument must take one of the two
values Scrollbar.HORIZONTAL
,
or Scrollbar.VERTICAL
,
indicating a horizontal or vertical scroll bar, respectively.
The parameters supplied to this constructor are subject to the
constraints described in setValues(int, int, int, int)
.
orientation
- indicates the orientation of the scroll bar.value
- the initial value of the scroll barvisible
- the visible amount of the scroll bar, typically
represented by the size of the bubbleminimum
- the minimum value of the scroll barmaximum
- the maximum value of the scroll barIllegalArgumentException
- when an illegal value for
the orientation
argument is suppliedHeadlessException
- if GraphicsEnvironment.isHeadless()
returns true.setValues(int, int, int, int)
,
GraphicsEnvironment.isHeadless()
public void addNotify()
Scrollbar
's peer. The peer allows you to modify
the appearance of the Scrollbar
without changing any of its
functionality.addNotify
in class Component
Component.isDisplayable()
,
Component.removeNotify()
,
Component.invalidate()
public int getOrientation()
getOrientation
in interface Adjustable
Scrollbar.HORIZONTAL
or
Scrollbar.VERTICAL
setOrientation(int)
public void setOrientation(int orientation)
orientation
- the orientation of this scroll bar, either
Scrollbar.HORIZONTAL
or
Scrollbar.VERTICAL
IllegalArgumentException
- if the value supplied
for orientation
is not a
legal valuegetOrientation()
public int getValue()
getValue
in interface Adjustable
getMinimum()
,
getMaximum()
public void setValue(int newValue)
If the value supplied is less than the current minimum
or greater than the current maximum - visibleAmount
,
then either minimum
or maximum - visibleAmount
is substituted, as appropriate.
Normally, a program should change a scroll bar's
value only by calling setValues
.
The setValues
method simultaneously
and synchronously sets the minimum, maximum, visible amount,
and value properties of a scroll bar, so that they are
mutually consistent.
Calling this method does not fire an
AdjustmentEvent
.
setValue
in interface Adjustable
newValue
- the new value of the scroll barsetValues(int, int, int, int)
,
getValue()
,
getMinimum()
,
getMaximum()
public int getMinimum()
getMinimum
in interface Adjustable
getValue()
,
getMaximum()
public void setMinimum(int newMinimum)
When setMinimum
is called, the minimum value
is changed, and other values (including the maximum, the
visible amount, and the current scroll bar value)
are changed to be consistent with the new minimum.
Normally, a program should change a scroll bar's minimum
value only by calling setValues
.
The setValues
method simultaneously
and synchronously sets the minimum, maximum, visible amount,
and value properties of a scroll bar, so that they are
mutually consistent.
Note that setting the minimum value to Integer.MAX_VALUE
will result in the new minimum value being set to
Integer.MAX_VALUE - 1
.
setMinimum
in interface Adjustable
newMinimum
- the new minimum value for this scroll barsetValues(int, int, int, int)
,
setMaximum(int)
public int getMaximum()
getMaximum
in interface Adjustable
getValue()
,
getMinimum()
public void setMaximum(int newMaximum)
When setMaximum
is called, the maximum value
is changed, and other values (including the minimum, the
visible amount, and the current scroll bar value)
are changed to be consistent with the new maximum.
Normally, a program should change a scroll bar's maximum
value only by calling setValues
.
The setValues
method simultaneously
and synchronously sets the minimum, maximum, visible amount,
and value properties of a scroll bar, so that they are
mutually consistent.
Note that setting the maximum value to Integer.MIN_VALUE
will result in the new maximum value being set to
Integer.MIN_VALUE + 1
.
setMaximum
in interface Adjustable
newMaximum
- the new maximum value
for this scroll barsetValues(int, int, int, int)
,
setMinimum(int)
public int getVisibleAmount()
When a scroll bar is used to select a range of values, the visible amount is used to represent the range of values that are currently visible. The size of the scroll bar's bubble (also called a thumb or scroll box), usually gives a visual representation of the relationship of the visible amount to the range of the scroll bar. Note that depending on platform, the value of the visible amount property may not be visually indicated by the size of the bubble.
The scroll bar's bubble may not be displayed when it is not
moveable (e.g. when it takes up the entire length of the
scroll bar's track, or when the scroll bar is disabled).
Whether the bubble is displayed or not will not affect
the value returned by getVisibleAmount
.
getVisibleAmount
in interface Adjustable
setVisibleAmount(int)
@Deprecated public int getVisible()
getVisibleAmount()
.public void setVisibleAmount(int newAmount)
When a scroll bar is used to select a range of values, the visible amount is used to represent the range of values that are currently visible. The size of the scroll bar's bubble (also called a thumb or scroll box), usually gives a visual representation of the relationship of the visible amount to the range of the scroll bar. Note that depending on platform, the value of the visible amount property may not be visually indicated by the size of the bubble.
The scroll bar's bubble may not be displayed when it is not
moveable (e.g. when it takes up the entire length of the
scroll bar's track, or when the scroll bar is disabled).
Whether the bubble is displayed or not will not affect
the value returned by getVisibleAmount
.
If the visible amount supplied is less than one
or greater than the current maximum - minimum
,
then either one
or maximum - minimum
is substituted, as appropriate.
Normally, a program should change a scroll bar's
value only by calling setValues
.
The setValues
method simultaneously
and synchronously sets the minimum, maximum, visible amount,
and value properties of a scroll bar, so that they are
mutually consistent.
setVisibleAmount
in interface Adjustable
newAmount
- the new visible amountgetVisibleAmount()
,
setValues(int, int, int, int)
public void setUnitIncrement(int v)
The unit increment is the value that is added or subtracted when the user activates the unit increment area of the scroll bar, generally through a mouse or keyboard gesture that the scroll bar receives as an adjustment event. The unit increment must be greater than zero. Attempts to set the unit increment to a value lower than 1 will result in a value of 1 being set.
In some operating systems, this property can be ignored by the underlying controls.
setUnitIncrement
in interface Adjustable
v
- the amount by which to increment or decrement
the scroll bar's valuegetUnitIncrement()
@Deprecated public void setLineIncrement(int v)
setUnitIncrement(int)
.v
- the increment valuepublic int getUnitIncrement()
The unit increment is the value that is added or subtracted when the user activates the unit increment area of the scroll bar, generally through a mouse or keyboard gesture that the scroll bar receives as an adjustment event. The unit increment must be greater than zero.
In some operating systems, this property can be ignored by the underlying controls.
getUnitIncrement
in interface Adjustable
setUnitIncrement(int)
@Deprecated public int getLineIncrement()
getUnitIncrement()
.public void setBlockIncrement(int v)
The block increment is the value that is added or subtracted when the user activates the block increment area of the scroll bar, generally through a mouse or keyboard gesture that the scroll bar receives as an adjustment event. The block increment must be greater than zero. Attempts to set the block increment to a value lower than 1 will result in a value of 1 being set.
setBlockIncrement
in interface Adjustable
v
- the amount by which to increment or decrement
the scroll bar's valuegetBlockIncrement()
@Deprecated public void setPageIncrement(int v)
setBlockIncrement()
.v
- the block incrementpublic int getBlockIncrement()
The block increment is the value that is added or subtracted when the user activates the block increment area of the scroll bar, generally through a mouse or keyboard gesture that the scroll bar receives as an adjustment event. The block increment must be greater than zero.
getBlockIncrement
in interface Adjustable
setBlockIncrement(int)
@Deprecated public int getPageIncrement()
getBlockIncrement()
.public void setValues(int value, int visible, int minimum, int maximum)
value
, visibleAmount
,
minimum
, and maximum
.
If the values supplied for these properties are inconsistent
or incorrect, they will be changed to ensure consistency.
This method simultaneously and synchronously sets the values
of four scroll bar properties, assuring that the values of
these properties are mutually consistent. It enforces the
following constraints:
maximum
must be greater than minimum
,
maximum - minimum
must not be greater
than Integer.MAX_VALUE
,
visibleAmount
must be greater than zero.
visibleAmount
must not be greater than
maximum - minimum
,
value
must not be less than minimum
,
and value
must not be greater than
maximum - visibleAmount
Calling this method does not fire an
AdjustmentEvent
.
value
- is the position in the current windowvisible
- is the visible amount of the scroll barminimum
- is the minimum value of the scroll barmaximum
- is the maximum value of the scroll barsetMinimum(int)
,
setMaximum(int)
,
setVisibleAmount(int)
,
setValue(int)
public boolean getValueIsAdjusting()
valueIsAdjusting
propertysetValueIsAdjusting(boolean)
public void setValueIsAdjusting(boolean b)
valueIsAdjusting
property.b
- new adjustment-in-progress statusgetValueIsAdjusting()
public void addAdjustmentListener(AdjustmentListener l)
AdjustmentEvent
from this scroll bar.
If l is null
, no exception is thrown and no
action is performed.
Refer to AWT Threading Issues for details on AWT's threading model.
addAdjustmentListener
in interface Adjustable
l
- the adjustment listenerremoveAdjustmentListener(java.awt.event.AdjustmentListener)
,
getAdjustmentListeners()
,
AdjustmentEvent
,
AdjustmentListener
public void removeAdjustmentListener(AdjustmentListener l)
AdjustmentEvent
from this scroll bar.
If l is null
, no exception is thrown and no action
is performed.
Refer to AWT Threading Issues for details on AWT's threading model.
removeAdjustmentListener
in interface Adjustable
l
- the adjustment listeneraddAdjustmentListener(java.awt.event.AdjustmentListener)
,
getAdjustmentListeners()
,
AdjustmentEvent
,
AdjustmentListener
public AdjustmentListener[] getAdjustmentListeners()
AdjustmentListener
s
or an empty array if no adjustment
listeners are currently registeredaddAdjustmentListener(java.awt.event.AdjustmentListener)
,
removeAdjustmentListener(java.awt.event.AdjustmentListener)
,
AdjustmentEvent
,
AdjustmentListener
public <T extends EventListener> T[] getListeners(Class<T> listenerType)
FooListener
s
upon this Scrollbar
.
FooListener
s are registered using the
addFooListener
method.
You can specify the listenerType
argument
with a class literal, such as
FooListener.class
.
For example, you can query a
Scrollbar c
for its mouse listeners with the following code:
MouseListener[] mls = (MouseListener[])(c.getListeners(MouseListener.class));If no such listeners exist, this method returns an empty array.
getListeners
in class Component
T
- the type of the listenerslistenerType
- the type of listeners requested; this parameter
should specify an interface that descends from
java.util.EventListener
FooListener
s on this component,
or an empty array if no such listeners have been addedClassCastException
- if listenerType
doesn't specify a class or interface that implements
java.util.EventListener
Component.getComponentListeners()
,
Component.getFocusListeners()
,
Component.getHierarchyListeners()
,
Component.getHierarchyBoundsListeners()
,
Component.getKeyListeners()
,
Component.getMouseListeners()
,
Component.getMouseMotionListeners()
,
Component.getMouseWheelListeners()
,
Component.getInputMethodListeners()
,
Component.getPropertyChangeListeners()
protected void processEvent(AWTEvent e)
AdjustmentEvent
, it invokes the
processAdjustmentEvent
method.
Otherwise, it invokes its superclass's
processEvent
method.
Note that if the event parameter is null
the behavior is unspecified and may result in an
exception.
processEvent
in class Component
e
- the eventAdjustmentEvent
,
processAdjustmentEvent(java.awt.event.AdjustmentEvent)
protected void processAdjustmentEvent(AdjustmentEvent e)
AdjustmentListener
objects.
This method is not called unless adjustment events are enabled for this component. Adjustment events are enabled when one of the following occurs:
AdjustmentListener
object is registered
via addAdjustmentListener
.
enableEvents
.
Note that if the event parameter is null
the behavior is unspecified and may result in an
exception.
e
- the adjustment eventAdjustmentEvent
,
AdjustmentListener
,
addAdjustmentListener(java.awt.event.AdjustmentListener)
,
Component.enableEvents(long)
protected String paramString()
Scrollbar
.
This method is intended to be used only for debugging purposes, and the
content and format of the returned string may vary between
implementations. The returned string may be empty but may not be
null
.paramString
in class Component
public AccessibleContext getAccessibleContext()
AccessibleContext
associated with this
Scrollbar
. For scrollbars, the
AccessibleContext
takes the form of an
AccessibleAWTScrollBar
. A new
AccessibleAWTScrollBar
instance is created if necessary.getAccessibleContext
in interface Accessible
getAccessibleContext
in class Component
AccessibleAWTScrollBar
that serves as the
AccessibleContext
of this ScrollBar
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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DRAFT 9-internal+0-adhoc.mlchung.jdk9-jdeps