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 {@link java.beans.XMLEncoder}. 

Also see:

setModel

Also see:

setOrientation

Also see:

setUnitIncrement

Also see:

setBlockIncrement

 public JScrollBar() 
{
        this(VERTICAL);
}

Creates a vertical scrollbar with the following initial values:

minimum = 0
maximum = 100
value = 0
extent = 10

 public JScrollBar(int orientation) 
{
        this(orientation, 0, 10, 0, 100);
}

Creates a scrollbar with the specified orientation and the following initial values:

minimum = 0
maximum = 100
value = 0
extent = 10

 public JScrollBar(int orientation,
    int value,
    int extent,
    int min,
    int max) 
{
        checkOrientation(orientation);
        this.unitIncrement = 1;
        this.blockIncrement = (extent == 0) ? 1 : extent;
        this.orientation = orientation;
        this.model = new DefaultBoundedRangeModel(value, extent, min, max);
        this.model.addChangeListener(fwdAdjustmentEvents);
        setRequestFocusEnabled(false);
        updateUI();
}

Creates a scrollbar with the specified orientation, value, extent, minimum, and maximum. The "extent" is the size of the viewable area. It is also known as the "visible amount".

Note: Use setBlockIncrement to set the block increment to a size slightly smaller than the view's extent. That way, when the user jumps the knob to an adjacent position, one or two lines of the original contents remain in view.

Throws:

IllegalArgumentException - if orientation is not one of VERTICAL, HORIZONTAL

Also see:

setOrientation
setValue
setVisibleAmount
setMinimum
setMaximum
exception: IllegalArgumentException - if orientation is not one of VERTICAL, HORIZONTAL

 public  void addAdjustmentListener(AdjustmentListener l) 
{
        listenerList.add(AdjustmentListener.class, l);
}

Adds an AdjustmentListener. Adjustment listeners are notified each time the scrollbar's model changes. Adjustment events are provided for backwards compatibility with java.awt.Scrollbar.

Note that the AdjustmentEvents type property will always have a placeholder value of AdjustmentEvent.TRACK because all changes to a BoundedRangeModels value are considered equivalent. To change the value of a BoundedRangeModel one just sets its value property, i.e. model.setValue(123). No information about the origin of the change, e.g. it's a block decrement, is provided. We don't try fabricate the origin of the change here.

 protected  void fireAdjustmentValueChanged(int id,
    int type,
    int value) 
{
        fireAdjustmentValueChanged(id, type, value, getValueIsAdjusting());
}

Notify listeners that the scrollbar's model has changed.

 public AccessibleContext getAccessibleContext() 
{
        if (accessibleContext == null) {
            accessibleContext = new AccessibleJScrollBar();
        }
        return accessibleContext;
}

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

 public AdjustmentListener[] getAdjustmentListeners() 
{
        return (AdjustmentListener[])listenerList.getListeners(
                AdjustmentListener.class);
}

Returns an array of all the AdjustmentListeners added to this JScrollBar with addAdjustmentListener().

 public int getBlockIncrement() 
{
        return blockIncrement;
}

For backwards compatibility with java.awt.Scrollbar.

 public int getBlockIncrement(int direction) 
{
        return blockIncrement;
}

Returns the amount to change the scrollbar's value by, given a block (usually "page") up/down request. A ScrollBarUI implementation typically calls this method when the user clicks above or below the scrollbar "knob" to change the value up or down by large amount. Subclasses my override this method to compute a value, e.g. the change required to scroll up or down one paragraph in a text document.

The JScrollPane component creates scrollbars (by default) that override this method and delegate to the viewports Scrollable view, if it has one. The Scrollable interface provides a more specialized version of this method.

 public int getMaximum() 
{
        return getModel().getMaximum();
}

The maximum value of the scrollbar is maximum - extent.

 public Dimension getMaximumSize() 
{
        Dimension pref = getPreferredSize();
        if (getOrientation() == VERTICAL) {
            return new Dimension(pref.width, Short.MAX_VALUE);
        } else {
            return new Dimension(Short.MAX_VALUE, pref.height);
        }
}

The scrollbar is flexible along it's scrolling axis and rigid along the other axis.

 public int getMinimum() 
{
        return getModel().getMinimum();
}

Returns the minimum value supported by the scrollbar (usually zero).

 public Dimension getMinimumSize() 
{
        Dimension pref = getPreferredSize();
        if (orientation == VERTICAL) {
            return new Dimension(pref.width, 5);
        } else {
            return new Dimension(5, pref.height);
        }
}

The scrollbar is flexible along it's scrolling axis and rigid along the other axis.

 public BoundedRangeModel getModel() 
{
        return model;
}

Returns data model that handles the scrollbar's four fundamental properties: minimum, maximum, value, extent.

 public int getOrientation() 
{
        return orientation;
}

Returns the component's orientation (horizontal or vertical).

 public ScrollBarUI getUI() 
{
        return (ScrollBarUI)ui;
}

Returns the delegate that implements the look and feel for this component.

 public String getUIClassID() 
{
        return uiClassID;
}

Returns the name of the LookAndFeel class for this component.

 public int getUnitIncrement() 
{
        return unitIncrement;
}

For backwards compatibility with java.awt.Scrollbar.

 public int getUnitIncrement(int direction) 
{
        return unitIncrement;
}

Returns the amount to change the scrollbar's value by, given a unit up/down request. A ScrollBarUI implementation typically calls this method when the user clicks on a scrollbar up/down arrow and uses the result to update the scrollbar's value. Subclasses my override this method to compute a value, e.g. the change required to scroll up or down one (variable height) line text or one row in a table.

The JScrollPane component creates scrollbars (by default) that override this method and delegate to the viewports Scrollable view, if it has one. The Scrollable interface provides a more specialized version of this method.

 public int getValue() 
{
        return getModel().getValue();
}

Returns the scrollbar's value.

 public boolean getValueIsAdjusting() 
{
        return getModel().getValueIsAdjusting();
}

True if the scrollbar knob is being dragged.

 public int getVisibleAmount() 
{
        return getModel().getExtent();
}

Returns the scrollbar's extent, aka its "visibleAmount". In many scrollbar look and feel implementations the size of the scrollbar "knob" or "thumb" is proportional to the extent.

 protected String paramString() 
{
        String orientationString = (orientation == HORIZONTAL ?
                                    "HORIZONTAL" : "VERTICAL");
        return super.paramString() +
        ",blockIncrement=" + blockIncrement +
        ",orientation=" + orientationString +
        ",unitIncrement=" + unitIncrement;
}

Returns a string representation of this JScrollBar. 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.

 public  void removeAdjustmentListener(AdjustmentListener l) 
{
        listenerList.remove(AdjustmentListener.class, l);
}

Removes an AdjustmentEvent listener.

 public  void setBlockIncrement(int blockIncrement) 
{
        int oldValue = this.blockIncrement;
        this.blockIncrement = blockIncrement;
        firePropertyChange("blockIncrement", oldValue, blockIncrement);
}

Sets the blockIncrement property.

Note, that if the argument is equal to the value of Integer.MIN_VALUE, the most look and feels will not provide the scrolling to the right/down.

 public  void setEnabled(boolean x) 
{
        super.setEnabled(x);
        Component[] children = getComponents();
        for(int i = 0; i <  children.length; i++) {
            children[i].setEnabled(x);
        }
}

Enables the component so that the knob position can be changed. When the disabled, the knob position cannot be changed.

 public  void setMaximum(int maximum) 
{
        getModel().setMaximum(maximum);
}

Sets the model's maximum property. Note that the scrollbar's value can only be set to maximum - extent.

 public  void setMinimum(int minimum) 
{
        getModel().setMinimum(minimum);
}

Sets the model's minimum property.

 public  void setModel(BoundedRangeModel newModel) 
{
        Integer oldValue = null;
        BoundedRangeModel oldModel = model;
        if (model != null) {
            model.removeChangeListener(fwdAdjustmentEvents);
            oldValue = Integer.valueOf(model.getValue());
        }
        model = newModel;
        if (model != null) {
            model.addChangeListener(fwdAdjustmentEvents);
        }
        firePropertyChange("model", oldModel, model);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_VALUE_PROPERTY,
                    oldValue, new Integer(model.getValue()));
        }
}

Sets the model that handles the scrollbar's four fundamental properties: minimum, maximum, value, extent.

 public  void setOrientation(int orientation) 
{
        checkOrientation(orientation);
        int oldValue = this.orientation;
        this.orientation = orientation;
        firePropertyChange("orientation", oldValue, orientation);
        if ((oldValue != orientation) && (accessibleContext != null)) {
            accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
                    ((oldValue == VERTICAL)
                     ? AccessibleState.VERTICAL : AccessibleState.HORIZONTAL),
                    ((orientation == VERTICAL)
                     ? AccessibleState.VERTICAL : AccessibleState.HORIZONTAL));
        }
        if (orientation != oldValue) {
            revalidate();
        }
}

Set the scrollbar's orientation to either VERTICAL or HORIZONTAL.

 public  void setUI(ScrollBarUI ui) 
{
        super.setUI(ui);
}

Sets the L&F object that renders this component.

 public  void setUnitIncrement(int unitIncrement) 
{
        int oldValue = this.unitIncrement;
        this.unitIncrement = unitIncrement;
        firePropertyChange("unitIncrement", oldValue, unitIncrement);
}

Sets the unitIncrement property.

Note, that if the argument is equal to the value of Integer.MIN_VALUE, the most look and feels will not provide the scrolling to the right/down.

 public  void setValue(int value) 
{
        BoundedRangeModel m = getModel();
        int oldValue = m.getValue();
        m.setValue(value);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_VALUE_PROPERTY,
                    Integer.valueOf(oldValue),
                    Integer.valueOf(m.getValue()));
        }
}

Sets the scrollbar's value. This method just forwards the value to the model.

 public  void setValueIsAdjusting(boolean b) 
{
        BoundedRangeModel m = getModel();
        boolean oldValue = m.getValueIsAdjusting();
        m.setValueIsAdjusting(b);
        if ((oldValue != b) && (accessibleContext != null)) {
            accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
                    ((oldValue) ? AccessibleState.BUSY : null),
                    ((b) ? AccessibleState.BUSY : null));
        }
}

Sets the model's valueIsAdjusting property. Scrollbar look and feel implementations should set this property to true when a knob drag begins, and to false when the drag ends. The scrollbar model will not generate ChangeEvents while valueIsAdjusting is true.

 public  void setValues(int newValue,
    int newExtent,
    int newMin,
    int newMax) 
{
        BoundedRangeModel m = getModel();
        int oldValue = m.getValue();
        m.setRangeProperties(newValue, newExtent, newMin, newMax, m.getValueIsAdjusting());
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_VALUE_PROPERTY,
                    Integer.valueOf(oldValue),
                    Integer.valueOf(m.getValue()));
        }
}

Sets the four BoundedRangeModel properties after forcing the arguments to obey the usual constraints:

minimum <= value <= value+extent <= maximum

 public  void setVisibleAmount(int extent) 
{
        getModel().setExtent(extent);
}

Set the model's extent property.

 public  void updateUI() 
{
        setUI((ScrollBarUI)UIManager.getUI(this));
}

Overrides JComponent.updateUI.