BasicScrollBarUI
Class BasicScrollBarUI
- java.lang.Object
-
- javax.swing.plaf.ComponentUI
-
- javax.swing.plaf.ScrollBarUI
-
- javax.swing.plaf.basic.BasicScrollBarUI
- All Implemented Interfaces:
- LayoutManager, SwingConstants
- Direct Known Subclasses:
- MetalScrollBarUI, SynthScrollBarUI
public class BasicScrollBarUI extends ScrollBarUI implements LayoutManager, SwingConstants
Implementation of ScrollBarUI for the Basic Look and Feel
Nested Classes
Modifier and Type | Class and Description |
---|---|
protected class |
BasicScrollBarUI.ArrowButtonListener Listener for cursor keys. |
protected class |
BasicScrollBarUI.ModelListener A listener to listen for model changes. |
class |
BasicScrollBarUI.PropertyChangeHandler |
protected class |
BasicScrollBarUI.ScrollListener Listener for scrolling events initiated in the |
protected class |
BasicScrollBarUI.TrackListener Track mouse drags. |
Fields
minimumThumbSize
protected Dimension minimumThumbSize
maximumThumbSize
protected Dimension maximumThumbSize
thumbHighlightColor
protected Color thumbHighlightColor
thumbLightShadowColor
protected Color thumbLightShadowColor
thumbDarkShadowColor
protected Color thumbDarkShadowColor
thumbColor
protected Color thumbColor
trackColor
protected Color trackColor
trackHighlightColor
protected Color trackHighlightColor
scrollbar
protected JScrollBar scrollbar
incrButton
protected JButton incrButton
decrButton
protected JButton decrButton
isDragging
protected boolean isDragging
trackListener
protected BasicScrollBarUI.TrackListener trackListener
buttonListener
protected BasicScrollBarUI.ArrowButtonListener buttonListener
modelListener
protected BasicScrollBarUI.ModelListener modelListener
thumbRect
protected Rectangle thumbRect
trackRect
protected Rectangle trackRect
trackHighlight
protected int trackHighlight
NO_HIGHLIGHT
protected static final int NO_HIGHLIGHT
DECREASE_HIGHLIGHT
protected static final int DECREASE_HIGHLIGHT
INCREASE_HIGHLIGHT
protected static final int INCREASE_HIGHLIGHT
scrollListener
protected BasicScrollBarUI.ScrollListener scrollListener
propertyChangeListener
protected PropertyChangeListener propertyChangeListener
scrollTimer
protected Timer scrollTimer
scrollBarWidth
protected int scrollBarWidth
Hint as to what width (when vertical) or height (when horizontal) should be.
- Since:
- 1.7
incrGap
protected int incrGap
Distance between the increment button and the track. This may be a negative number. If negative, then an overlap between the button and track will occur, which is useful for shaped buttons.
- Since:
- 1.7
decrGap
protected int decrGap
Distance between the decrement button and the track. This may be a negative number. If negative, then an overlap between the button and track will occur, which is useful for shaped buttons.
- Since:
- 1.7
Constructors
BasicScrollBarUI
public BasicScrollBarUI()
Methods
createUI
public static ComponentUI createUI(JComponent c)
configureScrollBarColors
protected void configureScrollBarColors()
installUI
public void installUI(JComponent c)
Description copied from class: ComponentUI
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:
- 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.
- Install a
LayoutManager
on the component if necessary. - Create/add any required sub-components to the component.
- Create/install event listeners on the component.
- Create/install a
PropertyChangeListener
on the component in order to detect and respond to component property changes appropriately. - Install keyboard UI (mnemonics, traversal, etc.) on the component.
- Initialize any appropriate instance data.
- Overrides:
-
installUI
in classComponentUI
- Parameters:
-
c
- the component where this UI delegate is being installed - See Also:
-
ComponentUI.uninstallUI(javax.swing.JComponent)
,JComponent.setUI(javax.swing.plaf.ComponentUI)
,JComponent.updateUI()
uninstallUI
public void uninstallUI(JComponent c)
Description copied from class: ComponentUI
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:
- Remove any UI-set borders from the component.
- Remove any UI-set layout managers on the component.
- Remove any UI-added sub-components from the component.
- Remove any UI-added event/property listeners from the component.
- Remove any UI-installed keyboard UI from the component.
- Nullify any allocated instance data objects to allow for GC.
- Overrides:
-
uninstallUI
in classComponentUI
- 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)
,JComponent.updateUI()
installDefaults
protected void installDefaults()
installComponents
protected void installComponents()
uninstallComponents
protected void uninstallComponents()
installListeners
protected void installListeners()
installKeyboardActions
protected void installKeyboardActions()
uninstallKeyboardActions
protected void uninstallKeyboardActions()
uninstallListeners
protected void uninstallListeners()
uninstallDefaults
protected void uninstallDefaults()
createTrackListener
protected BasicScrollBarUI.TrackListener createTrackListener()
createArrowButtonListener
protected BasicScrollBarUI.ArrowButtonListener createArrowButtonListener()
createModelListener
protected BasicScrollBarUI.ModelListener createModelListener()
createScrollListener
protected BasicScrollBarUI.ScrollListener createScrollListener()
createPropertyChangeListener
protected PropertyChangeListener createPropertyChangeListener()
setThumbRollover
protected void setThumbRollover(boolean active)
Sets whether or not the mouse is currently over the thumb.
- Parameters:
-
active
- True indicates the thumb is currently active. - Since:
- 1.5
isThumbRollover
public boolean isThumbRollover()
Returns true if the mouse is currently over the thumb.
- Returns:
- true if the thumb is currently active
- Since:
- 1.5
paint
public void paint(Graphics g, JComponent c)
Description copied from class: ComponentUI
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
in classComponentUI
- Parameters:
-
g
- theGraphics
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)
getPreferredSize
public Dimension getPreferredSize(JComponent c)
A vertical scrollbar's preferred width is the maximum of preferred widths of the (non null
) increment/decrement buttons, and the minimum width of the thumb. The preferred height is the sum of the preferred heights of the same parts. The basis for the preferred size of a horizontal scrollbar is similar.
The preferredSize
is only computed once, subsequent calls to this method just return a cached size.
- Overrides:
-
getPreferredSize
in classComponentUI
- Parameters:
-
c
- theJScrollBar
that's delegating this method to us - Returns:
- the preferred size of a Basic JScrollBar
- See Also:
-
getMaximumSize(javax.swing.JComponent)
,ComponentUI.getMinimumSize(javax.swing.JComponent)
getMaximumSize
public Dimension getMaximumSize(JComponent c)
Description copied from class: ComponentUI
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
in classComponentUI
- Parameters:
-
c
- The JScrollBar that's delegating this method to us. - Returns:
- new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE);
- See Also:
-
ComponentUI.getMinimumSize(javax.swing.JComponent)
,getPreferredSize(javax.swing.JComponent)
createDecreaseButton
protected JButton createDecreaseButton(int orientation)
createIncreaseButton
protected JButton createIncreaseButton(int orientation)
paintDecreaseHighlight
protected void paintDecreaseHighlight(Graphics g)
paintIncreaseHighlight
protected void paintIncreaseHighlight(Graphics g)
paintTrack
protected void paintTrack(Graphics g, JComponent c, Rectangle trackBounds)
paintThumb
protected void paintThumb(Graphics g, JComponent c, Rectangle thumbBounds)
getMinimumThumbSize
protected Dimension getMinimumThumbSize()
Returns the smallest acceptable size for the thumb. If the scrollbar becomes so small that this size isn't available, the thumb will be hidden.
Warning : the value returned by this method should not be be modified, it's a shared static constant.
- Returns:
- The smallest acceptable size for the thumb.
- See Also:
getMaximumThumbSize()
getMaximumThumbSize
protected Dimension getMaximumThumbSize()
Returns the largest acceptable size for the thumb. To create a fixed size thumb one make this method and getMinimumThumbSize
return the same value.
Warning : the value returned by this method should not be be modified, it's a shared static constant.
- Returns:
- The largest acceptable size for the thumb.
- See Also:
getMinimumThumbSize()
addLayoutComponent
public void addLayoutComponent(String name, Component child)
Description copied from interface: LayoutManager
If the layout manager uses a per-component string, adds the component comp
to the layout, associating it with the string specified by name
.
- Specified by:
-
addLayoutComponent
in interfaceLayoutManager
- Parameters:
-
name
- the string to be associated with the component -
child
- the component to be added
removeLayoutComponent
public void removeLayoutComponent(Component child)
Description copied from interface: LayoutManager
Removes the specified component from the layout.
- Specified by:
-
removeLayoutComponent
in interfaceLayoutManager
- Parameters:
-
child
- the component to be removed
preferredLayoutSize
public Dimension preferredLayoutSize(Container scrollbarContainer)
Description copied from interface: LayoutManager
Calculates the preferred size dimensions for the specified container, given the components it contains.
- Specified by:
-
preferredLayoutSize
in interfaceLayoutManager
- Parameters:
-
scrollbarContainer
- the container to be laid out - See Also:
LayoutManager.minimumLayoutSize(java.awt.Container)
minimumLayoutSize
public Dimension minimumLayoutSize(Container scrollbarContainer)
Description copied from interface: LayoutManager
Calculates the minimum size dimensions for the specified container, given the components it contains.
- Specified by:
-
minimumLayoutSize
in interfaceLayoutManager
- Parameters:
-
scrollbarContainer
- the component to be laid out - See Also:
LayoutManager.preferredLayoutSize(java.awt.Container)
layoutVScrollbar
protected void layoutVScrollbar(JScrollBar sb)
layoutHScrollbar
protected void layoutHScrollbar(JScrollBar sb)
layoutContainer
public void layoutContainer(Container scrollbarContainer)
Description copied from interface: LayoutManager
Lays out the specified container.
- Specified by:
-
layoutContainer
in interfaceLayoutManager
- Parameters:
-
scrollbarContainer
- the container to be laid out
setThumbBounds
protected void setThumbBounds(int x, int y, int width, int height)
Set the bounds of the thumb and force a repaint that includes the old thumbBounds and the new one.
- See Also:
getThumbBounds()
getThumbBounds
protected Rectangle getThumbBounds()
Return the current size/location of the thumb.
Warning : the value returned by this method should not be be modified, it's a reference to the actual rectangle, not a copy.
- Returns:
- The current size/location of the thumb.
- See Also:
setThumbBounds(int, int, int, int)
getTrackBounds
protected Rectangle getTrackBounds()
Returns the current bounds of the track, i.e. the space in between the increment and decrement buttons, less the insets. The value returned by this method is updated each time the scrollbar is laid out (validated).
Warning : the value returned by this method should not be be modified, it's a reference to the actual rectangle, not a copy.
- Returns:
- the current bounds of the scrollbar track
- See Also:
layoutContainer(java.awt.Container)
scrollByBlock
protected void scrollByBlock(int direction)
scrollByUnit
protected void scrollByUnit(int direction)
getSupportsAbsolutePositioning
public boolean getSupportsAbsolutePositioning()
Indicates whether the user can absolutely position the thumb with a mouse gesture (usually the middle mouse button).
- Returns:
- true if a mouse gesture can absolutely position the thumb
- Since:
- 1.5
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