BasicScrollPaneUI (Java Platform SE 8 ) (original) (raw)

java.lang.Object
- javax.swing.plaf.ComponentUI
- - javax.swing.plaf.ScrollPaneUI
    - - javax.swing.plaf.basic.BasicScrollPaneUI
All Implemented Interfaces:
ScrollPaneConstants
Direct Known Subclasses:
MetalScrollPaneUI, SynthScrollPaneUI

public class BasicScrollPaneUI
extends ScrollPaneUI
implements ScrollPaneConstants
A default L&F implementation of ScrollPaneUI.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	BasicScrollPaneUI.HSBChangeListener	Horizontal scrollbar listener.
protected class	BasicScrollPaneUI.MouseWheelHandler	MouseWheelHandler is an inner class which implements the MouseWheelListener interface.
class	BasicScrollPaneUI.PropertyChangeHandler
class	BasicScrollPaneUI.ViewportChangeHandler	Listener for viewport events.
class	BasicScrollPaneUI.VSBChangeListener	Vertical scrollbar listener.

Field Summary

Fields

Modifier and Type	Field	Description
protected ChangeListener	hsbChangeListener
protected JScrollPane	scrollpane
protected PropertyChangeListener	spPropertyChangeListener
protected ChangeListener	viewportChangeListener
protected ChangeListener	vsbChangeListener

   * ### Fields inherited from interface javax.swing.[ScrollPaneConstants](../../../../javax/swing/ScrollPaneConstants.html "interface in javax.swing")  
   `[COLUMN_HEADER](../../../../javax/swing/ScrollPaneConstants.html#COLUMN%5FHEADER), [HORIZONTAL_SCROLLBAR](../../../../javax/swing/ScrollPaneConstants.html#HORIZONTAL%5FSCROLLBAR), [HORIZONTAL_SCROLLBAR_ALWAYS](../../../../javax/swing/ScrollPaneConstants.html#HORIZONTAL%5FSCROLLBAR%5FALWAYS), [HORIZONTAL_SCROLLBAR_AS_NEEDED](../../../../javax/swing/ScrollPaneConstants.html#HORIZONTAL%5FSCROLLBAR%5FAS%5FNEEDED), [HORIZONTAL_SCROLLBAR_NEVER](../../../../javax/swing/ScrollPaneConstants.html#HORIZONTAL%5FSCROLLBAR%5FNEVER), [HORIZONTAL_SCROLLBAR_POLICY](../../../../javax/swing/ScrollPaneConstants.html#HORIZONTAL%5FSCROLLBAR%5FPOLICY), [LOWER_LEADING_CORNER](../../../../javax/swing/ScrollPaneConstants.html#LOWER%5FLEADING%5FCORNER), [LOWER_LEFT_CORNER](../../../../javax/swing/ScrollPaneConstants.html#LOWER%5FLEFT%5FCORNER), [LOWER_RIGHT_CORNER](../../../../javax/swing/ScrollPaneConstants.html#LOWER%5FRIGHT%5FCORNER), [LOWER_TRAILING_CORNER](../../../../javax/swing/ScrollPaneConstants.html#LOWER%5FTRAILING%5FCORNER), [ROW_HEADER](../../../../javax/swing/ScrollPaneConstants.html#ROW%5FHEADER), [UPPER_LEADING_CORNER](../../../../javax/swing/ScrollPaneConstants.html#UPPER%5FLEADING%5FCORNER), [UPPER_LEFT_CORNER](../../../../javax/swing/ScrollPaneConstants.html#UPPER%5FLEFT%5FCORNER), [UPPER_RIGHT_CORNER](../../../../javax/swing/ScrollPaneConstants.html#UPPER%5FRIGHT%5FCORNER), [UPPER_TRAILING_CORNER](../../../../javax/swing/ScrollPaneConstants.html#UPPER%5FTRAILING%5FCORNER), [VERTICAL_SCROLLBAR](../../../../javax/swing/ScrollPaneConstants.html#VERTICAL%5FSCROLLBAR), [VERTICAL_SCROLLBAR_ALWAYS](../../../../javax/swing/ScrollPaneConstants.html#VERTICAL%5FSCROLLBAR%5FALWAYS), [VERTICAL_SCROLLBAR_AS_NEEDED](../../../../javax/swing/ScrollPaneConstants.html#VERTICAL%5FSCROLLBAR%5FAS%5FNEEDED), [VERTICAL_SCROLLBAR_NEVER](../../../../javax/swing/ScrollPaneConstants.html#VERTICAL%5FSCROLLBAR%5FNEVER), [VERTICAL_SCROLLBAR_POLICY](../../../../javax/swing/ScrollPaneConstants.html#VERTICAL%5FSCROLLBAR%5FPOLICY), [VIEWPORT](../../../../javax/swing/ScrollPaneConstants.html#VIEWPORT)`

Constructor Summary

Constructors

Constructor	Description
BasicScrollPaneUI()

Method Summary

All Methods Static Methods Instance Methods Concrete Methods

Modifier and Type	Method	Description
protected ChangeListener	createHSBChangeListener()
protected MouseWheelListener	createMouseWheelListener()	Creates an instance of MouseWheelListener, which is added to the JScrollPane by installUI().
protected PropertyChangeListener	createPropertyChangeListener()	Creates an instance of PropertyChangeListener that's added to the JScrollPane by installUI().
static ComponentUI	createUI(JComponent x)
protected ChangeListener	createViewportChangeListener()
protected ChangeListener	createVSBChangeListener()
int	getBaseline(JComponent c, int width, int height)	Returns the baseline.
Component.BaselineResizeBehavior	getBaselineResizeBehavior(JComponent c)	Returns an enum indicating how the baseline of the component changes as the size changes.
Dimension	getMaximumSize(JComponent c)	Returns the specified component's maximum size appropriate for the look and feel.
protected void	installDefaults(JScrollPane scrollpane)
protected void	installKeyboardActions(JScrollPane c)
protected void	installListeners(JScrollPane c)
void	installUI(JComponent x)	Configures the specified component appropriately for the look and feel.
void	paint(Graphics g,JComponent c)	Paints the specified component appropriately for the look and feel.
protected void	syncScrollPaneWithViewport()
protected void	uninstallDefaults(JScrollPane c)
protected void	uninstallKeyboardActions(JScrollPane c)
protected void	uninstallListeners(JComponent c)
void	uninstallUI(JComponent c)	Reverses configuration which was done on the specified component duringinstallUI.
protected void	updateColumnHeader(PropertyChangeEvent e)
protected void	updateRowHeader(PropertyChangeEvent e)
protected void	updateScrollBarDisplayPolicy(PropertyChangeEvent e)
protected void	updateViewport(PropertyChangeEvent e)

   * ### Methods inherited from class javax.swing.plaf.[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")  
   `[contains](../../../../javax/swing/plaf/ComponentUI.html#contains-javax.swing.JComponent-int-int-), [getAccessibleChild](../../../../javax/swing/plaf/ComponentUI.html#getAccessibleChild-javax.swing.JComponent-int-), [getAccessibleChildrenCount](../../../../javax/swing/plaf/ComponentUI.html#getAccessibleChildrenCount-javax.swing.JComponent-), [getMinimumSize](../../../../javax/swing/plaf/ComponentUI.html#getMinimumSize-javax.swing.JComponent-), [getPreferredSize](../../../../javax/swing/plaf/ComponentUI.html#getPreferredSize-javax.swing.JComponent-), [update](../../../../javax/swing/plaf/ComponentUI.html#update-java.awt.Graphics-javax.swing.JComponent-)`  
   * ### Methods inherited from class java.lang.[Object](../../../../java/lang/Object.html "class in java.lang")  
   `[clone](../../../../java/lang/Object.html#clone--), [equals](../../../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../../../java/lang/Object.html#finalize--), [getClass](../../../../java/lang/Object.html#getClass--), [hashCode](../../../../java/lang/Object.html#hashCode--), [notify](../../../../java/lang/Object.html#notify--), [notifyAll](../../../../java/lang/Object.html#notifyAll--), [toString](../../../../java/lang/Object.html#toString--), [wait](../../../../java/lang/Object.html#wait--), [wait](../../../../java/lang/Object.html#wait-long-), [wait](../../../../java/lang/Object.html#wait-long-int-)`

Field Detail

 * #### scrollpane  
 protected [JScrollPane](../../../../javax/swing/JScrollPane.html "class in javax.swing") scrollpane  
 * #### vsbChangeListener  
 protected [ChangeListener](../../../../javax/swing/event/ChangeListener.html "interface in javax.swing.event") vsbChangeListener  
 * #### hsbChangeListener  
 protected [ChangeListener](../../../../javax/swing/event/ChangeListener.html "interface in javax.swing.event") hsbChangeListener  
 * #### viewportChangeListener  
 protected [ChangeListener](../../../../javax/swing/event/ChangeListener.html "interface in javax.swing.event") viewportChangeListener  
 * #### spPropertyChangeListener  
 protected [PropertyChangeListener](../../../../java/beans/PropertyChangeListener.html "interface in java.beans") spPropertyChangeListener

Constructor Detail

* #### BasicScrollPaneUI  
public BasicScrollPaneUI()

Method Detail

* #### createUI  
public static [ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf") createUI([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") x)  
* #### paint  
public void paint([Graphics](../../../../java/awt/Graphics.html "class in java.awt") g,  
                  [JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") c)  
Paints the specified component appropriately for the look and feel. This method is invoked from the `ComponentUI.update` method when the specified component is being painted. Subclasses should override this method and use the specified `Graphics` object to render the content of the component.  
Overrides:  
`[paint](../../../../javax/swing/plaf/ComponentUI.html#paint-java.awt.Graphics-javax.swing.JComponent-)` in class `[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")`  
Parameters:  
`g` \- the `Graphics` context in which to paint  
`c` \- the component being painted; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components  
See Also:  
[ComponentUI.update(java.awt.Graphics, javax.swing.JComponent)](../../../../javax/swing/plaf/ComponentUI.html#update-java.awt.Graphics-javax.swing.JComponent-)  
* #### getMaximumSize  
public [Dimension](../../../../java/awt/Dimension.html "class in java.awt") getMaximumSize([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") c)  
Returns the specified component's maximum size appropriate for the look and feel. If `null` is returned, the maximum size will be calculated by the component's layout manager instead (this is the preferred approach for any component with a specific layout manager installed). The default implementation of this method invokes `getPreferredSize` and returns that value.  
Overrides:  
`[getMaximumSize](../../../../javax/swing/plaf/ComponentUI.html#getMaximumSize-javax.swing.JComponent-)` in class `[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")`  
Parameters:  
`c` \- the component whose maximum size is being queried; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components  
Returns:  
new Dimension(Short.MAX\_VALUE, Short.MAX\_VALUE)  
See Also:  
[JComponent.getMaximumSize()](../../../../javax/swing/JComponent.html#getMaximumSize--), [LayoutManager2.maximumLayoutSize(java.awt.Container)](../../../../java/awt/LayoutManager2.html#maximumLayoutSize-java.awt.Container-)  
* #### installDefaults  
protected void installDefaults([JScrollPane](../../../../javax/swing/JScrollPane.html "class in javax.swing") scrollpane)  
* #### installListeners  
protected void installListeners([JScrollPane](../../../../javax/swing/JScrollPane.html "class in javax.swing") c)  
* #### installKeyboardActions  
protected void installKeyboardActions([JScrollPane](../../../../javax/swing/JScrollPane.html "class in javax.swing") c)  
* #### installUI  
public void installUI([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") x)  
Configures the specified component appropriately for the look and feel. This method is invoked when the `ComponentUI` instance is being installed as the UI delegate on the specified component. This method should completely configure the component for the look and feel, including the following:  
         1. Install default property values for color, fonts, borders, icons, opacity, etc. on the component. Whenever possible, property values initialized by the client program should _not_ be overridden.  
         2. Install a `LayoutManager` on the component if necessary.  
         3. Create/add any required sub-components to the component.  
         4. Create/install event listeners on the component.  
         5. Create/install a `PropertyChangeListener` on the component in order to detect and respond to component property changes appropriately.  
         6. Install keyboard UI (mnemonics, traversal, etc.) on the component.  
         7. Initialize any appropriate instance data.  
Overrides:  
`[installUI](../../../../javax/swing/plaf/ComponentUI.html#installUI-javax.swing.JComponent-)` in class `[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")`  
Parameters:  
`x` \- the component where this UI delegate is being installed  
See Also:  
[ComponentUI.uninstallUI(javax.swing.JComponent)](../../../../javax/swing/plaf/ComponentUI.html#uninstallUI-javax.swing.JComponent-), [JComponent.setUI(javax.swing.plaf.ComponentUI)](../../../../javax/swing/JComponent.html#setUI-javax.swing.plaf.ComponentUI-), [JComponent.updateUI()](../../../../javax/swing/JComponent.html#updateUI--)  
* #### uninstallDefaults  
protected void uninstallDefaults([JScrollPane](../../../../javax/swing/JScrollPane.html "class in javax.swing") c)  
* #### uninstallListeners  
protected void uninstallListeners([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") c)  
* #### uninstallKeyboardActions  
protected void uninstallKeyboardActions([JScrollPane](../../../../javax/swing/JScrollPane.html "class in javax.swing") c)  
* #### uninstallUI  
public void uninstallUI([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") c)  
Reverses configuration which was done on the specified component during`installUI`. This method is invoked when this`UIComponent` instance is being removed as the UI delegate for the specified component. This method should undo the configuration performed in `installUI`, being careful to leave the `JComponent` instance in a clean state (no extraneous listeners, look-and-feel-specific property objects, etc.). This should include the following:  
         1. Remove any UI-set borders from the component.  
         2. Remove any UI-set layout managers on the component.  
         3. Remove any UI-added sub-components from the component.  
         4. Remove any UI-added event/property listeners from the component.  
         5. Remove any UI-installed keyboard UI from the component.  
         6. Nullify any allocated instance data objects to allow for GC.  
Overrides:  
`[uninstallUI](../../../../javax/swing/plaf/ComponentUI.html#uninstallUI-javax.swing.JComponent-)` in class `[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")`  
Parameters:  
`c` \- the component from which this UI delegate is being removed; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components  
See Also:  
[ComponentUI.installUI(javax.swing.JComponent)](../../../../javax/swing/plaf/ComponentUI.html#installUI-javax.swing.JComponent-), [JComponent.updateUI()](../../../../javax/swing/JComponent.html#updateUI--)  
* #### syncScrollPaneWithViewport  
protected void syncScrollPaneWithViewport()  
* #### getBaseline  
public int getBaseline([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") c,  
                       int width,  
                       int height)  
Returns the baseline.  
Overrides:  
`[getBaseline](../../../../javax/swing/plaf/ComponentUI.html#getBaseline-javax.swing.JComponent-int-int-)` in class `[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")`  
Parameters:  
`c` \- `JComponent` baseline is being requested for  
`width` \- the width to get the baseline for  
`height` \- the height to get the baseline for  
Returns:  
baseline or a value < 0 indicating there is no reasonable baseline  
Throws:  
`[NullPointerException](../../../../java/lang/NullPointerException.html "class in java.lang")` \- if `c` is `null`  
`[IllegalArgumentException](../../../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if width or height is < 0  
Since:  
1.6  
See Also:  
[JComponent.getBaseline(int, int)](../../../../javax/swing/JComponent.html#getBaseline-int-int-)  
* #### getBaselineResizeBehavior  
public [Component.BaselineResizeBehavior](../../../../java/awt/Component.BaselineResizeBehavior.html "enum in java.awt") getBaselineResizeBehavior([JComponent](../../../../javax/swing/JComponent.html "class in javax.swing") c)  
Returns an enum indicating how the baseline of the component changes as the size changes.  
Overrides:  
`[getBaselineResizeBehavior](../../../../javax/swing/plaf/ComponentUI.html#getBaselineResizeBehavior-javax.swing.JComponent-)` in class `[ComponentUI](../../../../javax/swing/plaf/ComponentUI.html "class in javax.swing.plaf")`  
Parameters:  
`c` \- `JComponent` to return baseline resize behavior for  
Returns:  
an enum indicating how the baseline changes as the component size changes  
Throws:  
`[NullPointerException](../../../../java/lang/NullPointerException.html "class in java.lang")` \- if `c` is `null`  
Since:  
1.6  
See Also:  
[JComponent.getBaseline(int, int)](../../../../javax/swing/JComponent.html#getBaseline-int-int-)  
* #### createViewportChangeListener  
protected [ChangeListener](../../../../javax/swing/event/ChangeListener.html "interface in javax.swing.event") createViewportChangeListener()  
* #### createHSBChangeListener  
protected [ChangeListener](../../../../javax/swing/event/ChangeListener.html "interface in javax.swing.event") createHSBChangeListener()  
* #### createVSBChangeListener  
protected [ChangeListener](../../../../javax/swing/event/ChangeListener.html "interface in javax.swing.event") createVSBChangeListener()  
* #### createMouseWheelListener  
protected [MouseWheelListener](../../../../java/awt/event/MouseWheelListener.html "interface in java.awt.event") createMouseWheelListener()  
Creates an instance of MouseWheelListener, which is added to the JScrollPane by installUI(). The returned MouseWheelListener is used to handle mouse wheel-driven scrolling.  
Returns:  
MouseWheelListener which implements wheel-driven scrolling  
Since:  
1.4  
See Also:  
[installUI(javax.swing.JComponent)](../../../../javax/swing/plaf/basic/BasicScrollPaneUI.html#installUI-javax.swing.JComponent-), [BasicScrollPaneUI.MouseWheelHandler](../../../../javax/swing/plaf/basic/BasicScrollPaneUI.MouseWheelHandler.html "class in javax.swing.plaf.basic")  
* #### updateScrollBarDisplayPolicy  
protected void updateScrollBarDisplayPolicy([PropertyChangeEvent](../../../../java/beans/PropertyChangeEvent.html "class in java.beans") e)  
* #### updateViewport  
protected void updateViewport([PropertyChangeEvent](../../../../java/beans/PropertyChangeEvent.html "class in java.beans") e)  
* #### updateRowHeader  
protected void updateRowHeader([PropertyChangeEvent](../../../../java/beans/PropertyChangeEvent.html "class in java.beans") e)  
* #### updateColumnHeader  
protected void updateColumnHeader([PropertyChangeEvent](../../../../java/beans/PropertyChangeEvent.html "class in java.beans") e)  
* #### createPropertyChangeListener  
protected [PropertyChangeListener](../../../../java/beans/PropertyChangeListener.html "interface in java.beans") createPropertyChangeListener()  
Creates an instance of PropertyChangeListener that's added to the JScrollPane by installUI(). Subclasses can override this method to return a custom PropertyChangeListener, e.g.  
 class MyScrollPaneUI extends BasicScrollPaneUI {  
    protected PropertyChangeListener **createPropertyChangeListener**() {  
        return new MyPropertyChangeListener();  
    }  
    public class MyPropertyChangeListener extends PropertyChangeListener {  
        public void propertyChange(PropertyChangeEvent e) {  
            if (e.getPropertyName().equals("viewport")) {  
                // do some extra work when the viewport changes  
            }  
            super.propertyChange(e);  
        }  
    }  
 }  
       
See Also:  
[PropertyChangeListener](../../../../java/beans/PropertyChangeListener.html "interface in java.beans"), [installUI(javax.swing.JComponent)](../../../../javax/swing/plaf/basic/BasicScrollPaneUI.html#installUI-javax.swing.JComponent-)

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BasicScrollPaneUI (Java Platform SE 8 ) (original) (raw)

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail