javax.swing
Class JProgressBar

java.lang.Object   
  java.awt.Component   
      java.awt.Container   
          javax.swing.JComponent   
              javax.swing.JProgressBar

All Implemented Interfaces:

ImageObserver , MenuContainer , Serializable , Accessible , SwingConstants

public class JProgressBar
extends JComponent   
implements SwingConstants   , Accessible   

A component that, by default, displays an integer value within a bounded interval. A progress bar typically communicates the progress of some work by displaying its percentage of completion and possibly a textual display of this percentage.

To indicate that a task of unknown length is executing, you can put a progress bar into indeterminate mode. While the bar is in indeterminate mode, it animates constantly to show that work is occurring. As soon as you can determine the task's length and amount of progress, you should update the progress bar's value and switch it back to determinate mode.

Here is an example of creating a progress bar, where task is an object that returns information about the progress of some work:

progressBar = new JProgressBar(0, task.getLengthOfTask());
progressBar.setValue(0);
progressBar.setStringPainted(true);

Here is an example of updating the value of the progress bar:

progressBar.setValue(task.getCurrent());

Here is an example of putting a progress bar into indeterminate mode, and then switching back to determinate mode once the length of the task is known:

progressBar = new JProgressBar();
...//when the task of (initially) unknown length begins:
progressBar.setIndeterminate(true);
...//do some work; get length of task...
progressBar.setMaximum(newLength);
progressBar.setValue(newValue);
progressBar.setIndeterminate(false);

For complete examples and further documentation see How to Monitor Progress, a section in The Java Tutorial.

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:

BasicProgressBarUI , Serialized Form

Nested Class Summary

protected class

JProgressBar.AccessibleJProgressBar This class implements accessibility support for the JProgressBar 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.BltBufferStrategy , Component.FlipBufferStrategy

Field Summary

protected ChangeEvent	changeEvent Only one ChangeEvent is needed per instance since the event's only interesting property is the immutable source, which is the progress bar.
protected ChangeListener	changeListener Listens for change events sent by the progress bar's model, redispatching them to change-event listeners registered upon this progress bar.
protected BoundedRangeModel	model The object that holds the data for the progress bar.
protected int	orientation Whether the progress bar is horizontal or vertical.
protected boolean	paintBorder Whether to display a border around the progress bar.
protected boolean	paintString Whether to textually display a string on the progress bar.
protected String	progressString An optional string that can be displayed on the progress bar.

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

JProgressBar ()
Creates a horizontal progress bar that displays a border but no progress string.

JProgressBar (BoundedRangeModel newModel)
Creates a horizontal progress bar that uses the specified model to hold the progress bar's data.

JProgressBar (int orient)
Creates a progress bar with the specified orientation, which can be either JProgressBar.VERTICAL or JProgressBar.HORIZONTAL.

JProgressBar (int min, int max)
Creates a horizontal progress bar with the specified minimum and maximum.

JProgressBar (int orient, int min, int max)
Creates a progress bar using the specified orientation, minimum, and maximum.

Method Summary

void	addChangeListener (ChangeListener l) Adds the specified ChangeListener to the progress bar.
protected ChangeListener	createChangeListener () Subclasses that want to handle change events from the model differently can override this to return an instance of a custom ChangeListener implementation.
protected void	fireStateChanged () Notifies all listeners that have registered interest in ChangeEvents.
AccessibleContext	getAccessibleContext () Gets the AccessibleContext associated with this JProgressBar.
ChangeListener []	getChangeListeners () Returns an array of all the ChangeListeners added to this progress bar with addChangeListener.
int	getMaximum () Returns the progress bar's maximum value, which is stored in the progress bar's BoundedRangeModel.
int	getMinimum () Returns the progress bar's minimum value, which is stored in the progress bar's BoundedRangeModel.
BoundedRangeModel	getModel () Returns the data model used by this progress bar.
int	getOrientation () Returns JProgressBar.VERTICAL or JProgressBar.HORIZONTAL, depending on the orientation of the progress bar.
double	getPercentComplete () Returns the percent complete for the progress bar.
String	getString () Returns the current value of the progress string.
ProgressBarUI	getUI () Returns the look-and-feel object that renders this component.
String	getUIClassID () Returns the name of the look-and-feel class that renders this component.
int	getValue () Returns the progress bar's current value, which is stored in the progress bar's BoundedRangeModel.
boolean	isBorderPainted () Returns the borderPainted property.
boolean	isIndeterminate () Returns the value of the indeterminate property.
boolean	isStringPainted () Returns the value of the stringPainted property.
protected void	paintBorder (Graphics g) Paints the progress bar's border if the borderPainted property is true.
protected String	paramString () Returns a string representation of this JProgressBar.
void	removeChangeListener (ChangeListener l) Removes a ChangeListener from the progress bar.
void	setBorderPainted (boolean b) Sets the borderPainted property, which is true if the progress bar should paint its border.
void	setIndeterminate (boolean newValue) Sets the indeterminate property of the progress bar, which determines whether the progress bar is in determinate or indeterminate mode.
void	setMaximum (int n) Sets the progress bar's maximum value (stored in the progress bar's data model) to n.
void	setMinimum (int n) Sets the progress bar's minimum value (stored in the progress bar's data model) to n.
void	setModel (BoundedRangeModel newModel) Sets the data model used by the JProgressBar.
void	setOrientation (int newOrientation) Sets the progress bar's orientation to newOrientation, which must be JProgressBar.VERTICAL or JProgressBar.HORIZONTAL.
void	setString (String s) Sets the value of the progress string.
void	setStringPainted (boolean b) Sets the value of the stringPainted property, which determines whether the progress bar should render a progress string.
void	setUI (ProgressBarUI ui) Sets the look-and-feel object that renders this component.
void	setValue (int n) Sets the progress bar's current value (stored in the progress bar's data model) to n.
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 , getBorder , getBounds , getClientProperty , getComponentGraphics , getComponentPopupMenu , getConditionForKeyStroke , getDebugGraphicsOptions , getDefaultLocale , getFontMetrics