javax.swing

Class JSlider

java.lang.Object

java.awt.Component

java.awt.Container

javax.swing.JComponent

javax.swing.JSlider

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible, SwingConstants

public class JSlider
extends JComponent
implements SwingConstants, Accessible

A component that lets the user graphically select a value by sliding a knob within a bounded interval. The knob is always positioned at the points that match integer values within the specified interval.

The slider can show both major tick marks, and minor tick marks between the major ones. The number of values between the tick marks is controlled with setMajorTickSpacing and setMinorTickSpacing. Painting of tick marks is controlled by setPaintTicks.

Sliders can also print text labels at regular intervals (or at arbitrary locations) along the slider track. Painting of labels is controlled by setLabelTable and setPaintLabels.

For further information and examples see How to Use Sliders, a section in The Java Tutorial.

Warning: Swing is not thread safe. For more information see Swing's Threading Policy.

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.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	JSlider.AccessibleJSlider This class implements accessibility support for the JSlider class.

Nested classes/interfaces inherited from class javax.swing.JComponent

JComponent.AccessibleJComponent

Nested classes/interfaces inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

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

Field Summary

Fields

Modifier and Type	Field and Description
protected ChangeEvent	changeEvent Only one ChangeEvent is needed per slider instance since the event's only (read-only) state is the source property.
protected ChangeListener	changeListener The changeListener (no suffix) is the listener we add to the slider's model.
protected int	majorTickSpacing The number of values between the major tick marks -- the larger marks that break up the minor tick marks.
protected int	minorTickSpacing The number of values between the minor tick marks -- the smaller marks that occur between the major tick marks.
protected int	orientation Whether the slider is horizontal or vertical The default is horizontal.
protected BoundedRangeModel	sliderModel The data model that handles the numeric maximum value, minimum value, and current-position value for the slider.
protected boolean	snapToTicks If true, the knob (and the data value it represents) resolve to the closest tick mark next to where the user positioned the knob.

Fields inherited from class javax.swing.JComponent

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

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface javax.swing.SwingConstants

BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST

Fields inherited from interface java.awt.image.ImageObserver

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

Constructor Summary

Constructors

Constructor and Description
JSlider() Creates a horizontal slider with the range 0 to 100 and an initial value of 50.
JSlider(BoundedRangeModel brm) Creates a horizontal slider using the specified BoundedRangeModel.
JSlider(int orientation) Creates a slider using the specified orientation with the range 0 to 100 and an initial value of 50.
JSlider(int min, int max) Creates a horizontal slider using the specified min and max with an initial value equal to the average of the min plus max.
JSlider(int min, int max, int value) Creates a horizontal slider using the specified min, max and value.
JSlider(int orientation, int min, int max, int value) Creates a slider with the specified orientation and the specified minimum, maximum, and initial values.

Method Summary

Methods

Modifier and Type	Method and Description
void	addChangeListener(ChangeListener l) Adds a ChangeListener to the slider.
protected ChangeListener	createChangeListener() Subclasses that want to handle ChangeEvents from the model differently can override this to return an instance of a custom ChangeListener implementation.
Hashtable	createStandardLabels(int increment) Creates a Hashtable of numerical text labels, starting at the slider minimum, and using the increment specified.
Hashtable	createStandardLabels(int increment, int start) Creates a Hashtable of numerical text labels, starting at the starting point specified, and using the increment specified.
protected void	fireStateChanged() Send a ChangeEvent, whose source is this JSlider, to all ChangeListeners that have registered interest in ChangeEvents.
AccessibleContext	getAccessibleContext() Gets the AccessibleContext associated with this JSlider.
ChangeListener[]	getChangeListeners() Returns an array of all the ChangeListeners added to this JSlider with addChangeListener().
int	getExtent() Returns the "extent" from the BoundedRangeModel.
boolean	getInverted() Returns true if the value-range shown for the slider is reversed,
Dictionary	getLabelTable() Returns the dictionary of what labels to draw at which values.
int	getMajorTickSpacing() This method returns the major tick spacing.
int	getMaximum() Returns the maximum value supported by the slider from the BoundedRangeModel.
int	getMinimum() Returns the minimum value supported by the slider from the BoundedRangeModel.
int	getMinorTickSpacing() This method returns the minor tick spacing.
BoundedRangeModel	getModel() Returns the BoundedRangeModel that handles the slider's three fundamental properties: minimum, maximum, value.
int	getOrientation() Return this slider's vertical or horizontal orientation.
boolean	getPaintLabels() Tells if labels are to be painted.
boolean	getPaintTicks() Tells if tick marks are to be painted.
boolean	getPaintTrack() Tells if the track (area the slider slides in) is to be painted.
boolean	getSnapToTicks() Returns true if the knob (and the data value it represents) resolve to the closest tick mark next to where the user positioned the knob.
SliderUI	getUI() Gets the UI object which implements the L&F for this component.
String	getUIClassID() Returns the name of the L&F class that renders this component.
int	getValue() Returns the slider's current value from the BoundedRangeModel.
boolean	getValueIsAdjusting() Returns the valueIsAdjusting property from the model.
boolean	imageUpdate(Image img, int infoflags, int x, int y, int w, int h) Repaints the component when the image has changed.
protected String	paramString() Returns a string representation of this JSlider.
void	removeChangeListener(ChangeListener l) Removes a ChangeListener from the slider.
void	setExtent(int extent) Sets the size of the range "covered" by the knob.
void	setFont(Font font) Sets the font for this component.
void	setInverted(boolean b) Specify true to reverse the value-range shown for the slider and false to put the value range in the normal order.
void	setLabelTable(Dictionary labels) Used to specify what label will be drawn at any given value.
void	setMajorTickSpacing(int n) This method sets the major tick spacing.
void	setMaximum(int maximum) Sets the slider's maximum value to maximum.
void	setMinimum(int minimum) Sets the slider's minimum value to minimum.
void	setMinorTickSpacing(int n) This method sets the minor tick spacing.
void	setModel(BoundedRangeModel newModel) Sets the BoundedRangeModel that handles the slider's three fundamental properties: minimum, maximum, value.
void	setOrientation(int orientation) Set the slider's orientation to either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.
void	setPaintLabels(boolean b) Determines whether labels are painted on the slider.
void	setPaintTicks(boolean b) Determines whether tick marks are painted on the slider.
void	setPaintTrack(boolean b) Determines whether the track is painted on the slider.
void	setSnapToTicks(boolean b) Specifying true makes the knob (and the data value it represents) resolve to the closest tick mark next to where the user positioned the knob.
void	setUI(SliderUI ui) Sets the UI object which implements the L&F for this component.
void	setValue(int n) Sets the slider's current value to n.
void	setValueIsAdjusting(boolean b) Sets the model's valueIsAdjusting property.
protected void	updateLabelUIs() Updates the UIs for the labels in the label table by calling updateUI on each label.
void	updateUI() Resets the UI property to a value from the current look and feel.

Methods inherited from class javax.swing.JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, 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, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, 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, setEnabled, setFocusTraversalKeys, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update

Methods inherited from 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 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, 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, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, hide, 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, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods inherited from class java.lang.Object

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

Field Detail

sliderModel

protected BoundedRangeModel sliderModel

The data model that handles the numeric maximum value, minimum value, and current-position value for the slider.

majorTickSpacing

protected int majorTickSpacing

The number of values between the major tick marks -- the larger marks that break up the minor tick marks.

minorTickSpacing

protected int minorTickSpacing

The number of values between the minor tick marks -- the smaller marks that occur between the major tick marks.

See Also:

setMinorTickSpacing(int)

snapToTicks

protected boolean snapToTicks

If true, the knob (and the data value it represents) resolve to the closest tick mark next to where the user positioned the knob. The default is false.

See Also:

setSnapToTicks(boolean)

orientation

protected int orientation

Whether the slider is horizontal or vertical The default is horizontal.

See Also:

setOrientation(int)

changeListener

protected ChangeListener changeListener

The changeListener (no suffix) is the listener we add to the slider's model. This listener is initialized to the ChangeListener returned from createChangeListener, which by default just forwards events to ChangeListeners (if any) added directly to the slider.

See Also:

addChangeListener(javax.swing.event.ChangeListener), createChangeListener()

changeEvent

protected transient ChangeEvent changeEvent

Only one ChangeEvent is needed per slider instance since the event's only (read-only) state is the source property. The source of events generated here is always "this". The event is lazily created the first time that an event notification is fired.

See Also:

fireStateChanged()

Constructor Detail

JSlider

public JSlider()

Creates a horizontal slider with the range 0 to 100 and an initial value of 50.

JSlider

public JSlider(int orientation)

Creates a slider using the specified orientation with the range 0 to 100 and an initial value of 50. The orientation can be either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.

Parameters:

orientation - the orientation of the slider

Throws:

IllegalArgumentException - if orientation is not one of VERTICAL, HORIZONTAL

See Also:

setOrientation(int)

JSlider

public JSlider(int min,
       int max)

Creates a horizontal slider using the specified min and max with an initial value equal to the average of the min plus max.

The BoundedRangeModel that holds the slider's data handles any issues that may arise from improperly setting the minimum and maximum values on the slider. See the BoundedRangeModel documentation for details.

Parameters:

min - the minimum value of the slider

max - the maximum value of the slider

See Also:

BoundedRangeModel, setMinimum(int), setMaximum(int)

JSlider

public JSlider(int min,
       int max,
       int value)

Creates a horizontal slider using the specified min, max and value.

The BoundedRangeModel that holds the slider's data handles any issues that may arise from improperly setting the minimum, initial, and maximum values on the slider. See the BoundedRangeModel documentation for details.

Parameters:

min - the minimum value of the slider

max - the maximum value of the slider

value - the initial value of the slider

See Also:

BoundedRangeModel, setMinimum(int), setMaximum(int), setValue(int)

JSlider

public JSlider(int orientation,
       int min,
       int max,
       int value)

Creates a slider with the specified orientation and the specified minimum, maximum, and initial values. The orientation can be either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.

The BoundedRangeModel that holds the slider's data handles any issues that may arise from improperly setting the minimum, initial, and maximum values on the slider. See the BoundedRangeModel documentation for details.

Parameters:

orientation - the orientation of the slider

min - the minimum value of the slider

max - the maximum value of the slider

value - the initial value of the slider

Throws:

IllegalArgumentException - if orientation is not one of VERTICAL, HORIZONTAL

See Also:

BoundedRangeModel, setOrientation(int), setMinimum(int), setMaximum(int), setValue(int)

JSlider

public JSlider(BoundedRangeModel brm)

Creates a horizontal slider using the specified BoundedRangeModel.

Method Detail

getUI

public SliderUI getUI()

Gets the UI object which implements the L&F for this component.

Returns:

the SliderUI object that implements the Slider L&F

setUI

public void setUI(SliderUI ui)

Sets the UI object which implements the L&F for this component.

Parameters:

ui - the SliderUI L&F object

See Also:

UIDefaults.getUI(javax.swing.JComponent)

updateUI

public void updateUI()

Resets the UI property to a value from the current look and feel.

Overrides:

updateUI in class JComponent

See Also:

JComponent.updateUI()

getUIClassID

public String getUIClassID()

Returns the name of the L&F class that renders this component.

Overrides:

getUIClassID in class JComponent

Returns:

"SliderUI"

See Also:

JComponent.getUIClassID(), UIDefaults.getUI(javax.swing.JComponent)

createChangeListener

protected ChangeListener createChangeListener()

Subclasses that want to handle ChangeEvents from the model differently can override this to return an instance of a custom ChangeListener implementation. The default ChangeListener simply calls the fireStateChanged method to forward ChangeEvents to the ChangeListeners that have been added directly to the slider.

See Also:

changeListener, fireStateChanged(), ChangeListener, BoundedRangeModel

addChangeListener

public void addChangeListener(ChangeListener l)

Adds a ChangeListener to the slider.

Parameters:

l - the ChangeListener to add

See Also:

fireStateChanged(), removeChangeListener(javax.swing.event.ChangeListener)

removeChangeListener

public void removeChangeListener(ChangeListener l)

Removes a ChangeListener from the slider.

Parameters:

l - the ChangeListener to remove

See Also:

fireStateChanged(), addChangeListener(javax.swing.event.ChangeListener)

getChangeListeners

public ChangeListener[] getChangeListeners()

Returns an array of all the ChangeListeners added to this JSlider with addChangeListener().

Returns:

all of the ChangeListeners added or an empty array if no listeners have been added

Since:

1.4

fireStateChanged

protected void fireStateChanged()

Send a ChangeEvent, whose source is this JSlider, to all ChangeListeners that have registered interest in ChangeEvents. This method is called each time a ChangeEvent is received from the model.

The event instance is created if necessary, and stored in changeEvent.

See Also:

addChangeListener(javax.swing.event.ChangeListener), EventListenerList

getModel

public BoundedRangeModel getModel()

Returns the BoundedRangeModel that handles the slider's three fundamental properties: minimum, maximum, value.

Returns:

the data model for this component

See Also:

setModel(javax.swing.BoundedRangeModel), BoundedRangeModel

setModel

public void setModel(BoundedRangeModel newModel)

Sets the BoundedRangeModel that handles the slider's three fundamental properties: minimum, maximum, value.

Attempts to pass a null model to this method result in undefined behavior, and, most likely, exceptions.

Parameters:

newModel - the new, non-null BoundedRangeModel to use

See Also:

getModel(), BoundedRangeModel

getValue

public int getValue()

Returns the slider's current value from the BoundedRangeModel.

Returns:

the current value of the slider

See Also:

setValue(int), BoundedRangeModel.getValue()

setValue

public void setValue(int n)

Sets the slider's current value to n. This method forwards the new value to the model.

The data model (an instance of BoundedRangeModel) handles any mathematical issues arising from assigning faulty values. See the BoundedRangeModel documentation for details.

If the new value is different from the previous value, all change listeners are notified.

Parameters:

n - the new value

See Also:

getValue(), addChangeListener(javax.swing.event.ChangeListener), BoundedRangeModel.setValue(int)

getMinimum

public int getMinimum()

Returns the minimum value supported by the slider from the BoundedRangeModel.

Returns:

the value of the model's minimum property

See Also:

setMinimum(int), BoundedRangeModel.getMinimum()

setMinimum

public void setMinimum(int minimum)

Sets the slider's minimum value to minimum. This method forwards the new minimum value to the model.

The data model (an instance of BoundedRangeModel) handles any mathematical issues arising from assigning faulty values. See the BoundedRangeModel documentation for details.

If the new minimum value is different from the previous minimum value, all change listeners are notified.

Parameters:

minimum - the new minimum

See Also:

getMinimum(), addChangeListener(javax.swing.event.ChangeListener), BoundedRangeModel.setMinimum(int)

getMaximum

public int getMaximum()

Returns the maximum value supported by the slider from the BoundedRangeModel.

Returns:

the value of the model's maximum property

See Also:

setMaximum(int), BoundedRangeModel.getMaximum()

setMaximum

public void setMaximum(int maximum)

Sets the slider's maximum value to maximum. This method forwards the new maximum value to the model.

The data model (an instance of BoundedRangeModel) handles any mathematical issues arising from assigning faulty values. See the BoundedRangeModel documentation for details.

If the new maximum value is different from the previous maximum value, all change listeners are notified.

Parameters:

maximum - the new maximum

See Also:

getMaximum(), addChangeListener(javax.swing.event.ChangeListener), BoundedRangeModel.setMaximum(int)

getValueIsAdjusting

public boolean getValueIsAdjusting()

Returns the valueIsAdjusting property from the model. For details on how this is used, see the setValueIsAdjusting documentation.

Returns:

the value of the model's valueIsAdjusting property

See Also:

setValueIsAdjusting(boolean)

setValueIsAdjusting

public void setValueIsAdjusting(boolean b)

Sets the model's valueIsAdjusting property. Slider look and feel implementations should set this property to true when a knob drag begins, and to false when the drag ends.

Parameters:

b - the new value for the valueIsAdjusting property

See Also:

getValueIsAdjusting(), BoundedRangeModel.setValueIsAdjusting(boolean)

getExtent

public int getExtent()

Returns the "extent" from the BoundedRangeModel. This respresents the range of values "covered" by the knob.

Returns:

an int representing the extent

See Also:

setExtent(int), BoundedRangeModel.getExtent()

setExtent

public void setExtent(int extent)

Sets the size of the range "covered" by the knob. Most look and feel implementations will change the value by this amount if the user clicks on either side of the knob. This method just forwards the new extent value to the model.

The data model (an instance of BoundedRangeModel) handles any mathematical issues arising from assigning faulty values. See the BoundedRangeModel documentation for details.

If the new extent value is different from the previous extent value, all change listeners are notified.

Parameters:

extent - the new extent

See Also:

getExtent(), BoundedRangeModel.setExtent(int)

getOrientation

public int getOrientation()

Return this slider's vertical or horizontal orientation.

Returns:

SwingConstants.VERTICAL or SwingConstants.HORIZONTAL

See Also:

setOrientation(int)

setOrientation

public void setOrientation(int orientation)

Set the slider's orientation to either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.

Parameters:

orientation - HORIZONTAL or VERTICAL

Throws:

IllegalArgumentException - if orientation is not one of VERTICAL, HORIZONTAL

See Also:

getOrientation()

setFont

public void setFont(Font font)

Sets the font for this component.

Overrides:

setFont in class JComponent

Parameters:

font - the desired Font for this component

Since:

1.6

See Also:

Component.getFont()

imageUpdate

public boolean imageUpdate(Image img,
                  int infoflags,
                  int x,
                  int y,
                  int w,
                  int h)

Repaints the component when the image has changed. This imageUpdate method of an ImageObserver is called when more information about an image which had been previously requested using an asynchronous routine such as the drawImage method of Graphics becomes available. See the definition of imageUpdate for more information on this method and its arguments.

The imageUpdate method of Component incrementally draws an image on the component as more of the bits of the image are available.

If the system property awt.image.incrementaldraw is missing or has the value true, the image is incrementally drawn. If the system property has any other value, then the image is not drawn until it has been completely loaded.

Also, if incremental drawing is in effect, the value of the system property awt.image.redrawrate is interpreted as an integer to give the maximum redraw rate, in milliseconds. If the system property is missing or cannot be interpreted as an integer, the redraw rate is once every 100ms.

The interpretation of the x, y, width, and height arguments depends on the value of the infoflags argument.

Specified by:

imageUpdate in interface ImageObserver

Overrides:

imageUpdate in class Component

Parameters:

img - the image being observed

infoflags - see imageUpdate for more information

x - the x coordinate

y - the y coordinate

w - the width

h - the height

Returns:

false if the infoflags indicate that the image is completely loaded; true otherwise.

Since:

1.7

See Also:

ImageObserver, Graphics.drawImage(Image, int, int, Color, java.awt.image.ImageObserver), Graphics.drawImage(Image, int, int, java.awt.image.ImageObserver), Graphics.drawImage(Image, int, int, int, int, Color, java.awt.image.ImageObserver), Graphics.drawImage(Image, int, int, int, int, java.awt.image.ImageObserver), ImageObserver.imageUpdate(java.awt.Image, int, int, int, int, int)

getLabelTable

public Dictionary getLabelTable()

Returns the dictionary of what labels to draw at which values.

Returns:

the Dictionary containing labels and where to draw them

setLabelTable

public void setLabelTable(Dictionary labels)

Used to specify what label will be drawn at any given value. The key-value pairs are of this format: { Integer value, java.swing.JComponent label }.

An easy way to generate a standard table of value labels is by using the createStandardLabels method.

Once the labels have been set, this method calls updateLabelUIs(). Note that the labels are only painted if the paintLabels property is true.

Parameters:

labels - new Dictionary of labels, or null to remove all labels

See Also:

createStandardLabels(int), getLabelTable(), setPaintLabels(boolean)

updateLabelUIs

protected void updateLabelUIs()

Updates the UIs for the labels in the label table by calling updateUI on each label. The UIs are updated from the current look and feel. The labels are also set to their preferred size.

See Also:

setLabelTable(java.util.Dictionary), JComponent.updateUI()

createStandardLabels

public Hashtable createStandardLabels(int increment)

Creates a Hashtable of numerical text labels, starting at the slider minimum, and using the increment specified. For example, if you call createStandardLabels( 10 ) and the slider minimum is zero, then labels will be created for the values 0, 10, 20, 30, and so on.

For the labels to be drawn on the slider, the returned Hashtable must be passed into setLabelTable, and setPaintLabels must be set to true.

For further details on the makeup of the returned Hashtable, see the setLabelTable documentation.

Parameters:

increment - distance between labels in the generated hashtable

Returns:

a new Hashtable of labels

Throws:

IllegalArgumentException - if increment is less than or equal to zero

See Also:

setLabelTable(java.util.Dictionary), setPaintLabels(boolean)

createStandardLabels

public Hashtable createStandardLabels(int increment,
                             int start)

Creates a Hashtable of numerical text labels, starting at the starting point specified, and using the increment specified. For example, if you call createStandardLabels( 10, 2 ), then labels will be created for the values 2, 12, 22, 32, and so on.

For the labels to be drawn on the slider, the returned Hashtable must be passed into setLabelTable, and setPaintLabels must be set to true.

For further details on the makeup of the returned Hashtable, see the setLabelTable documentation.

Parameters:

increment - distance between labels in the generated hashtable

start - value at which the labels will begin

Returns:

a new Hashtable of labels

Throws:

IllegalArgumentException - if start is out of range, or if increment is less than or equal to zero

See Also:

setLabelTable(java.util.Dictionary), setPaintLabels(boolean)

getInverted

public boolean getInverted()

Returns true if the value-range shown for the slider is reversed,

Returns:

true if the slider values are reversed from their normal order

See Also:

setInverted(boolean)

setInverted

public void setInverted(boolean b)

Specify true to reverse the value-range shown for the slider and false to put the value range in the normal order. The order depends on the slider's ComponentOrientation property. Normal (non-inverted) horizontal sliders with a ComponentOrientation value of LEFT_TO_RIGHT have their maximum on the right. Normal horizontal sliders with a ComponentOrientation value of RIGHT_TO_LEFT have their maximum on the left. Normal vertical sliders have their maximum on the top. These labels are reversed when the slider is inverted.

By default, the value of this property is false.

Parameters:

b - true to reverse the slider values from their normal order

getMajorTickSpacing

public int getMajorTickSpacing()

This method returns the major tick spacing. The number that is returned represents the distance, measured in values, between each major tick mark. If you have a slider with a range from 0 to 50 and the major tick spacing is set to 10, you will get major ticks next to the following values: 0, 10, 20, 30, 40, 50.

Returns:

the number of values between major ticks

See Also:

setMajorTickSpacing(int)

setMajorTickSpacing

public void setMajorTickSpacing(int n)

This method sets the major tick spacing. The number that is passed in represents the distance, measured in values, between each major tick mark. If you have a slider with a range from 0 to 50 and the major tick spacing is set to 10, you will get major ticks next to the following values: 0, 10, 20, 30, 40, 50.

In order for major ticks to be painted, setPaintTicks must be set to true.

This method will also set up a label table for you. If there is not already a label table, and the major tick spacing is > 0, and getPaintLabels returns true, a standard label table will be generated (by calling createStandardLabels) with labels at the major tick marks. For the example above, you would get text labels: "0", "10", "20", "30", "40", "50". The label table is then set on the slider by calling setLabelTable.

Parameters:

n - new value for the majorTickSpacing property

See Also:

getMajorTickSpacing(), setPaintTicks(boolean), setLabelTable(java.util.Dictionary), createStandardLabels(int)

getMinorTickSpacing

public int getMinorTickSpacing()

This method returns the minor tick spacing. The number that is returned represents the distance, measured in values, between each minor tick mark. If you have a slider with a range from 0 to 50 and the minor tick spacing is set to 10, you will get minor ticks next to the following values: 0, 10, 20, 30, 40, 50.

Returns:

the number of values between minor ticks

See Also:

getMinorTickSpacing()

setMinorTickSpacing

public void setMinorTickSpacing(int n)

This method sets the minor tick spacing. The number that is passed in represents the distance, measured in values, between each minor tick mark. If you have a slider with a range from 0 to 50 and the minor tick spacing is set to 10, you will get minor ticks next to the following values: 0, 10, 20, 30, 40, 50.

In order for minor ticks to be painted, setPaintTicks must be set to true.

Parameters:

n - new value for the minorTickSpacing property

See Also:

getMinorTickSpacing(), setPaintTicks(boolean)

getSnapToTicks

public boolean getSnapToTicks()

Returns true if the knob (and the data value it represents) resolve to the closest tick mark next to where the user positioned the knob.

Returns:

true if the value snaps to the nearest tick mark, else false

See Also:

setSnapToTicks(boolean)

setSnapToTicks

public void setSnapToTicks(boolean b)

Specifying true makes the knob (and the data value it represents) resolve to the closest tick mark next to where the user positioned the knob. By default, this property is false.

Parameters:

b - true to snap the knob to the nearest tick mark

See Also:

getSnapToTicks()

getPaintTicks

public boolean getPaintTicks()

Tells if tick marks are to be painted.

Returns:

true if tick marks are painted, else false

See Also:

setPaintTicks(boolean)

setPaintTicks

public void setPaintTicks(boolean b)

Determines whether tick marks are painted on the slider. By default, this property is false.

Parameters:

b - whether or not tick marks should be painted

See Also:

getPaintTicks()

getPaintTrack

public boolean getPaintTrack()

Tells if the track (area the slider slides in) is to be painted.

Returns:

true if track is painted, else false

See Also:

setPaintTrack(boolean)

setPaintTrack

public void setPaintTrack(boolean b)

Determines whether the track is painted on the slider. By default, this property is true.

Parameters:

b - whether or not to paint the slider track

See Also:

getPaintTrack()

getPaintLabels

public boolean getPaintLabels()

Tells if labels are to be painted.

Returns:

true if labels are painted, else false

See Also:

setPaintLabels(boolean)

setPaintLabels

public void setPaintLabels(boolean b)

Determines whether labels are painted on the slider.

This method will also set up a label table for you. If there is not already a label table, and the major tick spacing is > 0, a standard label table will be generated (by calling createStandardLabels) with labels at the major tick marks. The label table is then set on the slider by calling setLabelTable.

By default, this property is false.

Parameters:

b - whether or not to paint labels

See Also:

getPaintLabels(), getLabelTable(), createStandardLabels(int)

paramString

protected String paramString()

Returns a string representation of this JSlider. 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.

Overrides:

paramString in class JComponent

Returns:

a string representation of this JSlider.

getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this JSlider. For sliders, the AccessibleContext takes the form of an AccessibleJSlider. A new AccessibleJSlider instance is created if necessary.

Specified by:

getAccessibleContext in interface Accessible

Overrides:

getAccessibleContext in class JComponent

Returns:

an AccessibleJSlider that serves as the AccessibleContext of this JSlider