- java.lang.Object
-
- java.awt.Component
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- java.awt.Container
-
- javax.swing.JComponent
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- javax.swing.JLayer<V>
-
- Type Parameters:
V
- the type ofJLayer
's view component
- All Implemented Interfaces:
- ImageObserver, MenuContainer, PropertyChangeListener, Serializable, EventListener, Accessible, Scrollable
public final class JLayer<V extends Component> extends JComponent implements Scrollable, PropertyChangeListener, Accessible
JLayer
is a universal decorator for Swing components which enables you to implement various advanced painting effects as well as receive notifications of allAWTEvent
s generated within its borders.JLayer
delegates the handling of painting and input events to aLayerUI
object, which performs the actual decoration. The custom painting implemented in theLayerUI
and events notification work for the JLayer itself and all its subcomponents. This combination enables you to enrich existing components by adding new advanced functionality such as temporary locking of a hierarchy, data tips for compound components, enhanced mouse scrolling etc and so on.JLayer
is a good solution if you only need to do custom painting over compound component or catch input events from its subcomponents.import javax.swing.*; import javax.swing.plaf.LayerUI; import java.awt.*; public class JLayerSample { private static JLayer<JComponent> createLayer() { // This custom layerUI will fill the layer with translucent green // and print out all mouseMotion events generated within its borders LayerUI<JComponent> layerUI = new LayerUI<JComponent>() { public void paint(Graphics g, JComponent c) { // paint the layer as is super.paint(g, c); // fill it with the translucent green g.setColor(new Color(0, 128, 0, 128)); g.fillRect(0, 0, c.getWidth(), c.getHeight()); } public void installUI(JComponent c) { super.installUI(c); // enable mouse motion events for the layer's subcomponents ((JLayer) c).setLayerEventMask(AWTEvent.MOUSE_MOTION_EVENT_MASK); } public void uninstallUI(JComponent c) { super.uninstallUI(c); // reset the layer event mask ((JLayer) c).setLayerEventMask(0); } // overridden method which catches MouseMotion events public void eventDispatched(AWTEvent e, JLayer<? extends JComponent> l) { System.out.println("AWTEvent detected: " + e); } }; // create a component to be decorated with the layer JPanel panel = new JPanel(); panel.add(new JButton("JButton")); // create the layer for the panel using our custom layerUI return new JLayer<JComponent>(panel, layerUI); } private static void createAndShowGUI() { final JFrame frame = new JFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // work with the layer as with any other Swing component frame.add(createLayer()); frame.setSize(200, 200); frame.setLocationRelativeTo(null); frame.setVisible(true); } public static void main(String[] args) throws Exception { SwingUtilities.invokeAndWait(new Runnable() { public void run() { createAndShowGUI(); } }); } }
Note:JLayer
doesn't support the following methods:Container.add(java.awt.Component)
Container.add(String, java.awt.Component)
Container.add(java.awt.Component, int)
Container.add(java.awt.Component, Object)
Container.add(java.awt.Component, Object, int)
UnsupportedOperationException
to be thrown, to add a component toJLayer
usesetView(Component)
orsetGlassPane(JPanel)
.- Since:
- 1.7
- See Also:
JLayer(Component)
,setView(Component)
,getView()
,LayerUI
,JLayer(Component, LayerUI)
,setUI(javax.swing.plaf.LayerUI)
,getUI()
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Nested Class Summary
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Nested classes/interfaces inherited from class javax.swing.JComponent
JComponent.AccessibleJComponent
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Nested classes/interfaces inherited from class java.awt.Container
Container.AccessibleAWTContainer
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Nested classes/interfaces inherited from class java.awt.Component
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
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Field Summary
-
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
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Fields inherited from class java.awt.Component
BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
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Constructor Summary
Constructors Constructor and Description JLayer()
JLayer(V view)
Creates a newJLayer
object with defaultLayerUI
.JLayer(V view, LayerUI<V> ui)
Creates a newJLayer
object with the specified view component andLayerUI
object.
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Method Summary
Methods Modifier and Type Method and Description protected void
addImpl(Component comp, Object constraints, int index)
This method is not supported byJLayer
and always throwsUnsupportedOperationException
void
addNotify()
Notifies this component that it now has a parent component.JPanel
createGlassPane()
Called by the constructor methods to create a defaultglassPane
.void
doLayout()
Delegates its functionality to theLayerUI.doLayout(JLayer)
method, ifLayerUI
is set.AccessibleContext
getAccessibleContext()
Gets the AccessibleContext associated with thisJLayer
.JPanel
getGlassPane()
Returns theJLayer
's glassPane component ornull
.long
getLayerEventMask()
Returns the bitmap of event mask to receive by thisJLayer
and itsLayerUI
.Dimension
getPreferredScrollableViewportSize()
Returns the preferred size of the viewport for a view component.int
getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)
Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one block of rows or columns, depending on the value of orientation.boolean
getScrollableTracksViewportHeight()
Returnsfalse
to indicate that the height of the viewport does not determine the height of the layer, unless the preferred height of the layer is smaller than the height of the viewport.boolean
getScrollableTracksViewportWidth()
Returnsfalse
to indicate that the width of the viewport does not determine the width of the layer, unless the preferred width of the layer is smaller than the width of the viewport.int
getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)
Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one new row or column, depending on the value of orientation.LayerUI<? super V>
getUI()
Returns theLayerUI
for thisJLayer
.V
getView()
Returns theJLayer
's view component ornull
.boolean
isOptimizedDrawingEnabled()
TheJLayer
overrides the default implementation of this method (inJComponent
) to returnfalse
.protected boolean
isPaintingOrigin()
Always returnstrue
to cause painting to originate fromJLayer
, or one of its ancestors.void
paint(Graphics g)
Delegates all painting to theLayerUI
object.protected void
paintComponent(Graphics g)
This method is empty, because all painting is done bypaint(Graphics)
andComponentUI.update(Graphics, JComponent)
methodsvoid
paintImmediately(int x, int y, int w, int h)
Delegates its functionality to theLayerUI.paintImmediately(int, int, int, int, JLayer)
method, ifLayerUI
is set.void
propertyChange(PropertyChangeEvent evt)
This method gets called when a bound property is changed.void
remove(Component comp)
Removes the specified component from this container.void
removeAll()
Removes all the components from this container.void
removeNotify()
Notifies this component that it no longer has a parent component.void
setBorder(Border border)
A non-null
border, or non-zero insets, isn't supported, to prevent the geometry of this component from becoming complex enough to inhibit subclassing ofLayerUI
class.void
setGlassPane(JPanel glassPane)
Sets theJLayer
's glassPane component, which can benull
.void
setLayerEventMask(long layerEventMask)
Enables the events from JLayer and all its descendants defined by the specified event mask parameter to be delivered to theLayerUI.eventDispatched(AWTEvent, JLayer)
method.void
setLayout(LayoutManager mgr)
Sets the layout manager for this container.void
setUI(LayerUI<? super V> ui)
Sets theLayerUI
which will perform painting and receive input events for thisJLayer
.void
setView(V view)
Sets theJLayer
's view component, which can benull
.void
updateUI()
Delegates its functionality to theLayerUI.updateUI(JLayer)
method, ifLayerUI
is set.-
Methods inherited from class javax.swing.JComponent
addAncestorListener, 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, getUIClassID, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isPaintingForPrint, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paintBorder, paintChildren, paintImmediately, paramString, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update
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Methods inherited from class java.awt.Container
add, add, add, add, add, addContainerListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, 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, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, transferFocusDownCycle, validate, validateTree
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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, imageUpdate, 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
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Constructor Detail
-
JLayer
public JLayer()
-
JLayer
public JLayer(V view)
Creates a newJLayer
object with defaultLayerUI
.- Parameters:
view
- the component to be decorated by thisJLayer
- See Also:
setUI(javax.swing.plaf.LayerUI<? super V>)
-
-
Method Detail
-
getView
public V getView()
Returns theJLayer
's view component ornull
.
This is a bound property.- Returns:
- the
JLayer
's view component ornull
if none exists - See Also:
setView(Component)
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setView
public void setView(V view)
Sets theJLayer
's view component, which can benull
.
This is a bound property.- Parameters:
view
- the view component for thisJLayer
- See Also:
getView()
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setUI
public void setUI(LayerUI<? super V> ui)
Sets theLayerUI
which will perform painting and receive input events for thisJLayer
.- Parameters:
ui
- theLayerUI
for thisJLayer
-
getUI
public LayerUI<? super V> getUI()
Returns theLayerUI
for thisJLayer
.- Returns:
- the
LayerUI
for thisJLayer
-
getGlassPane
public JPanel getGlassPane()
Returns theJLayer
's glassPane component ornull
.
This is a bound property.- Returns:
- the
JLayer
's glassPane component ornull
if none exists - See Also:
setGlassPane(JPanel)
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setGlassPane
public void setGlassPane(JPanel glassPane)
Sets theJLayer
's glassPane component, which can benull
.
This is a bound property.- Parameters:
glassPane
- the glassPane component of thisJLayer
- See Also:
getGlassPane()
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createGlassPane
public JPanel createGlassPane()
Called by the constructor methods to create a defaultglassPane
. By default this method creates a new JPanel with visibility set to true and opacity set to false.- Returns:
- the default
glassPane
-
setLayout
public void setLayout(LayoutManager mgr)
Sets the layout manager for this container. This method is overridden to prevent the layout manager from being set. Note: Ifmgr
is non-null
, this method will throw an exception as layout managers are not supported on aJLayer
.- Overrides:
setLayout
in classContainer
- Parameters:
mgr
- the specified layout manager- Throws:
IllegalArgumentException
- this method is not supported- See Also:
Container.doLayout()
,Container.getLayout()
,Container.invalidate()
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setBorder
public void setBorder(Border border)
A non-null
border, or non-zero insets, isn't supported, to prevent the geometry of this component from becoming complex enough to inhibit subclassing ofLayerUI
class. To create aJLayer
with a border, add it to aJPanel
that has a border. Note: Ifborder
is non-null
, this method will throw an exception as borders are not supported on aJLayer
.- Overrides:
setBorder
in classJComponent
- Parameters:
border
- theBorder
to set- Throws:
IllegalArgumentException
- this method is not supported- See Also:
Border
,CompoundBorder
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addImpl
protected void addImpl(Component comp, Object constraints, int index)
This method is not supported byJLayer
and always throwsUnsupportedOperationException
- Overrides:
addImpl
in classContainer
- Parameters:
comp
- the component to be addedconstraints
- an object expressing layout constraints for this componentindex
- the position in the container's list at which to insert the component, where-1
means append to the end- Throws:
UnsupportedOperationException
- this method is not supported- See Also:
setView(Component)
,setGlassPane(JPanel)
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remove
public void remove(Component comp)
Removes the specified component from this container. This method also notifies the layout manager to remove the component from this container's layout via theremoveLayoutComponent
method.This method changes layout-related information, and therefore, invalidates the component hierarchy. If the container has already been displayed, the hierarchy must be validated thereafter in order to reflect the changes.
- Overrides:
remove
in classContainer
- Parameters:
comp
- the component to be removed- See Also:
Container.add(java.awt.Component)
,Container.invalidate()
,Container.validate()
,Container.remove(int)
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removeAll
public void removeAll()
Removes all the components from this container. This method also notifies the layout manager to remove the components from this container's layout via theremoveLayoutComponent
method.This method changes layout-related information, and therefore, invalidates the component hierarchy. If the container has already been displayed, the hierarchy must be validated thereafter in order to reflect the changes.
- Overrides:
removeAll
in classContainer
- See Also:
Container.add(java.awt.Component)
,Container.remove(int)
,Container.invalidate()
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isPaintingOrigin
protected boolean isPaintingOrigin()
Always returnstrue
to cause painting to originate fromJLayer
, or one of its ancestors.- Overrides:
isPaintingOrigin
in classJComponent
- Returns:
- true
- See Also:
JComponent.isPaintingOrigin()
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paintImmediately
public void paintImmediately(int x, int y, int w, int h)
Delegates its functionality to theLayerUI.paintImmediately(int, int, int, int, JLayer)
method, ifLayerUI
is set.- Overrides:
paintImmediately
in classJComponent
- Parameters:
x
- the x value of the region to be paintedy
- the y value of the region to be paintedw
- the width of the region to be paintedh
- the height of the region to be painted- See Also:
JComponent.repaint(long, int, int, int, int)
,JComponent.isPaintingOrigin()
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paint
public void paint(Graphics g)
Delegates all painting to theLayerUI
object.- Overrides:
paint
in classJComponent
- Parameters:
g
- theGraphics
to render to- See Also:
JComponent.paintComponent(java.awt.Graphics)
,JComponent.paintBorder(java.awt.Graphics)
,JComponent.paintChildren(java.awt.Graphics)
,JComponent.getComponentGraphics(java.awt.Graphics)
,JComponent.repaint(long, int, int, int, int)
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paintComponent
protected void paintComponent(Graphics g)
This method is empty, because all painting is done bypaint(Graphics)
andComponentUI.update(Graphics, JComponent)
methods- Overrides:
paintComponent
in classJComponent
- Parameters:
g
- theGraphics
object to protect- See Also:
JComponent.paint(java.awt.Graphics)
,ComponentUI
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isOptimizedDrawingEnabled
public boolean isOptimizedDrawingEnabled()
TheJLayer
overrides the default implementation of this method (inJComponent
) to returnfalse
. This ensures that the drawing machinery will call theJLayer
'spaint
implementation rather than messaging theJLayer
's children directly.- Overrides:
isOptimizedDrawingEnabled
in classJComponent
- Returns:
- false
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propertyChange
public void propertyChange(PropertyChangeEvent evt)
This method gets called when a bound property is changed.- Specified by:
propertyChange
in interfacePropertyChangeListener
- Parameters:
evt
- A PropertyChangeEvent object describing the event source and the property that has changed.
-
setLayerEventMask
public void setLayerEventMask(long layerEventMask)
Enables the events from JLayer and all its descendants defined by the specified event mask parameter to be delivered to theLayerUI.eventDispatched(AWTEvent, JLayer)
method. Events are delivered provided thatLayerUI
is set for thisJLayer
and theJLayer
is displayable. The following example shows how to correctly use this method in theLayerUI
implementations:public void installUI(JComponent c) { super.installUI(c); JLayer l = (JLayer) c; // this LayerUI will receive only key and focus events l.setLayerEventMask(AWTEvent.KEY_EVENT_MASK | AWTEvent.FOCUS_EVENT_MASK); } public void uninstallUI(JComponent c) { super.uninstallUI(c); JLayer l = (JLayer) c; // JLayer must be returned to its initial state l.setLayerEventMask(0); }
By defaultJLayer
receives no events and its event mask is0
.- Parameters:
layerEventMask
- the bitmask of event types to receive- See Also:
getLayerEventMask()
,LayerUI.eventDispatched(AWTEvent, JLayer)
,Component.isDisplayable()
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getLayerEventMask
public long getLayerEventMask()
Returns the bitmap of event mask to receive by thisJLayer
and itsLayerUI
. It means thatLayerUI.eventDispatched(AWTEvent, JLayer)
method will only receive events that match the event mask. By defaultJLayer
receives no events.- Returns:
- the bitmask of event types to receive for this
JLayer
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updateUI
public void updateUI()
Delegates its functionality to theLayerUI.updateUI(JLayer)
method, ifLayerUI
is set.- Overrides:
updateUI
in classJComponent
- See Also:
JComponent.setUI(javax.swing.plaf.ComponentUI)
,UIManager.getLookAndFeel()
,UIManager.getUI(javax.swing.JComponent)
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getPreferredScrollableViewportSize
public Dimension getPreferredScrollableViewportSize()
Returns the preferred size of the viewport for a view component. If the view component of this layer implementsScrollable
, this method delegates its implementation to the view component.- Specified by:
getPreferredScrollableViewportSize
in interfaceScrollable
- Returns:
- the preferred size of the viewport for a view component
- See Also:
Scrollable
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getScrollableBlockIncrement
public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)
Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one block of rows or columns, depending on the value of orientation. If the view component of this layer implementsScrollable
, this method delegates its implementation to the view component.- Specified by:
getScrollableBlockIncrement
in interfaceScrollable
- Parameters:
visibleRect
- The view area visible within the viewportorientation
- Either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.direction
- Less than zero to scroll up/left, greater than zero for down/right.- Returns:
- the "block" increment for scrolling in the specified direction
- See Also:
Scrollable
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getScrollableTracksViewportHeight
public boolean getScrollableTracksViewportHeight()
Returnsfalse
to indicate that the height of the viewport does not determine the height of the layer, unless the preferred height of the layer is smaller than the height of the viewport. If the view component of this layer implementsScrollable
, this method delegates its implementation to the view component.- Specified by:
getScrollableTracksViewportHeight
in interfaceScrollable
- Returns:
- whether the layer should track the height of the viewport
- See Also:
Scrollable
-
getScrollableTracksViewportWidth
public boolean getScrollableTracksViewportWidth()
Returnsfalse
to indicate that the width of the viewport does not determine the width of the layer, unless the preferred width of the layer is smaller than the width of the viewport. If the view component of this layer implementsScrollable
, this method delegates its implementation to the view component.- Specified by:
getScrollableTracksViewportWidth
in interfaceScrollable
- Returns:
- whether the layer should track the width of the viewport
- See Also:
Scrollable
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getScrollableUnitIncrement
public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)
Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one new row or column, depending on the value of orientation. Ideally, components should handle a partially exposed row or column by returning the distance required to completely expose the item. Scrolling containers, likeJScrollPane
, will use this method each time the user requests a unit scroll. If the view component of this layer implementsScrollable
, this method delegates its implementation to the view component.- Specified by:
getScrollableUnitIncrement
in interfaceScrollable
- Parameters:
visibleRect
- The view area visible within the viewportorientation
- Either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.direction
- Less than zero to scroll up/left, greater than zero for down/right.- Returns:
- The "unit" increment for scrolling in the specified direction. This value should always be positive.
- See Also:
Scrollable
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addNotify
public void addNotify()
Notifies this component that it now has a parent component. When this method is invoked, the chain of parent components is set up withKeyboardAction
event listeners. This method is called by the toolkit internally and should not be called directly by programs.
-
removeNotify
public void removeNotify()
Notifies this component that it no longer has a parent component. When this method is invoked, anyKeyboardAction
s set up in the the chain of parent components are removed. This method is called by the toolkit internally and should not be called directly by programs.
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doLayout
public void doLayout()
Delegates its functionality to theLayerUI.doLayout(JLayer)
method, ifLayerUI
is set.- Overrides:
doLayout
in classContainer
- See Also:
LayoutManager.layoutContainer(java.awt.Container)
,Container.setLayout(java.awt.LayoutManager)
,Container.validate()
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getAccessibleContext
public AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with thisJLayer
.- Specified by:
getAccessibleContext
in interfaceAccessible
- Overrides:
getAccessibleContext
in classJComponent
- Returns:
- the AccessibleContext associated with this
JLayer
.
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