javax.swing
Class Box

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

All Implemented Interfaces:

ImageObserver , MenuContainer , Serializable , Accessible

public class Box
extends JComponent
implements Accessible

A lightweight container that uses a BoxLayout object as its layout manager. Box provides several class methods that are useful for containers using BoxLayout -- even non-Box containers.

The Box class can create several kinds of invisible components that affect layout: glue, struts, and rigid areas. If all the components your Box contains have a fixed size, you might want to use a glue component (returned by createGlue) to control the components' positions. If you need a fixed amount of space between two components, try using a strut (createHorizontalStrut or createVerticalStrut). If you need an invisible component that always takes up the same amount of space, get it by invoking createRigidArea.

If you are implementing a BoxLayout you can find further information and examples in How to Use BoxLayout , 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:

BoxLayout

Nested Class Summary
protected  class	Box.AccessibleBox           This class implements accessibility support for the Box class.
static class	Box.Filler           An implementation of a lightweight component that participates in layout but has no view.

 

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.BaselineResizeBehavior , Component.BltBufferStrategy , Component.FlipBufferStrategy

 

Field Summary
protected   AccessibleContext	accessibleContext           The currently set AccessibleContext object.

 

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 java.awt.image. ImageObserver
ABORT , ALLBITS , ERROR , FRAMEBITS , HEIGHT , PROPERTIES , SOMEBITS , WIDTH

 

Constructor Summary
Box (int axis)           Creates a Box that displays its components along the the specified axis.

 

Method Summary
static  Component	createGlue ()           Creates an invisible "glue" component that can be useful in a Box whose visible components have a maximum width (for a horizontal box) or height (for a vertical box).
static  Box	createHorizontalBox ()           Creates a Box that displays its components from left to right.
static  Component	createHorizontalGlue ()           Creates a horizontal glue component.
static  Component	createHorizontalStrut (int width)           Creates an invisible, fixed-width component.
static  Component	createRigidArea ( Dimension  d)           Creates an invisible component that's always the specified size.
static  Box	createVerticalBox ()           Creates a Box that displays its components from top to bottom.
static  Component	createVerticalGlue ()           Creates a vertical glue component.
static  Component	createVerticalStrut (int height)           Creates an invisible, fixed-height component.
AccessibleContext	getAccessibleContext ()           Gets the AccessibleContext associated with this Box.
protected  void	paintComponent ( Graphics           Paints this Box.
void	setLayout ( LayoutManager  l)           Throws an AWTError, since a Box can use only a BoxLayout.

 

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 , 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 , isDoubleBuffered , isLightweightComponent , isManagingFocus , isOpaque , isOptimizedDrawingEnabled , isPaintingForPrint , isPaintingTile , isRequestFocusEnabled , isValidateRoot , paint , paintBorder , paintChildren , paintComponent , paintImmediately , paintImmediately , paramString , print , printAll , printBorder , printChildren , printComponent , processComponentKeyEvent , processKeyBinding , processKeyEvent , processMouseEvent , processMouseMotionEvent , putClientProperty , registerKeyboardAction , registerKeyboardAction , removeAncestorListener , removeNotify , removeVetoableChangeListener , repaint , repaint , requestDefaultFocus , requestFocus , requestFocus , requestFocusInWindow , requestFocusInWindow , resetKeyboardActions , reshape , revalidate , scrollRectToVisible , setActionMap , setAlignmentX , setAlignmentY , setAutoscrolls , setBackground , setBorder , setComponentPopupMenu , setDebugGraphicsOptions , setDefaultLocale , setDoubleBuffered , setEnabled , setFocusTraversalKeys , setFont , setForeground , setInheritsPopupMenu , setInputMap , setInputVerifier , setMaximumSize , setMinimumSize , setNextFocusableComponent , setOpaque , setPreferredSize , setRequestFocusEnabled , setToolTipText , setTransferHandler , setUI , setVerifyInputWhenFocusTarget , setVisible , unregisterKeyboardAction , update , updateUI

 

Methods inherited from class java.awt. Container

add , add , add , add , add , addContainerListener , addImpl , addPropertyChangeListener , addPropertyChangeListener , applyComponentOrientation , areFocusTraversalKeysSet , countComponents , deliverEvent , doLayout , 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 , remove , removeAll , removeContainerListener , setComponentZOrder , setFocusCycleRoot , setFocusTraversalPolicy , setFocusTraversalPolicyProvider , transferFocusBackward , transferFocusDownCycle , validate , validateTree

 

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 , hide , 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 , transferFocusUpCycle

 

Methods inherited from class java.lang. Object
clone , equals , finalize , getClass , hashCode , notify , notifyAll , wait , wait , wait

 

Constructor Field Detail

Box accessibleContext

public 
protected AccessibleContextBox accessibleContext (int axis) 

Creates a Box that displays its components along the the specified axis. The currently set AccessibleContext object.

Parameters:

axis - can be BoxLayout.X_AXIS , BoxLayout.Y_AXIS , BoxLayout.LINE_AXIS or BoxLayout.PAGE_AXIS .

Throws:

AWTError - if the axis is invalid

See Also:

createHorizontalBox() , createVerticalBox()

Method Constructor Detail

createHorizontalBox Box

public static Box
public createHorizontalBox Box () (int axis) 

Creates a Box that displays its components from left to right. If you want a Box that respects the component orientation you should create the Box using the constructor and pass in BoxLayout.LINE_AXIS, eg:

 Box lineBox = new Box(BoxLayout.LINE_AXIS);
 

Creates a Box that displays its components along the the specified axis.

Parameters:

axis - can be BoxLayout.X_AXIS , BoxLayout.Y_AXIS , BoxLayout.LINE_AXIS or BoxLayout.PAGE_AXIS .

Throws:

AWTError - if the axis is invalid

Returns: See Also:

the box createHorizontalBox() , createVerticalBox()

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Method Detail

createVerticalBox createHorizontalBox

public static BoxcreateVerticalBox createHorizontalBox ()

Creates a Box that displays its components from top left to bottom. right. If you want a Box that respects the component orientation you should create the Box using the constructor and pass in BoxLayout.PAGE_AXIS, BoxLayout.LINE_AXIS, eg:

 Box lineBox = new Box(BoxLayout.PAGE_AXIS);
 Box(BoxLayout.LINE_AXIS);
 

Returns:

the box

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createRigidArea createVerticalBox

public static ComponentBoxcreateRigidArea createVerticalBox ( Dimension d) () 

Creates an invisible component that's always the specified size. Creates a Box that displays its components from top to bottom. If you want a Box that respects the component orientation you should create the Box using the constructor and pass in BoxLayout.PAGE_AXIS, eg:

 Box lineBox = new Box(BoxLayout.PAGE_AXIS);
 

Parameters:

d - the dimensions of the invisible component

Returns:

the component

See Also:

createGlue() , createHorizontalStrut(int) , createVerticalStrut(int) the box

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createHorizontalStrut createRigidArea

public static ComponentcreateHorizontalStrut createRigidArea (int width) ( Dimension d) 

Creates an invisible, fixed-width component. In a horizontal box, you typically use this method to force a certain amount of space between two components. In a vertical box, you might use this method to force the box to be at least the specified width. The invisible component has no height unless excess space is available, in which case it takes its share of available space, just like any other component that has no maximum height. Creates an invisible component that's always the specified size.

Parameters:

width d - the width dimensions of the invisible component, in pixels >= 0 component

Returns:

the component

See Also:

createVerticalStrut(int) createGlue() , createGlue() createHorizontalStrut(int) , createRigidArea(java.awt.Dimension) createVerticalStrut(int)

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createVerticalStrut createHorizontalStrut

public static ComponentcreateVerticalStrut createHorizontalStrut (int height) (int width) 

Creates an invisible, fixed-height fixed-width component. In a vertical horizontal box, you typically use this method to force a certain amount of space between two components. In a horizontal vertical box, you might use this method to force the box to be at least the specified height. width. The invisible component has no width height unless excess space is available, in which case it takes its share of available space, just like any other component that has no maximum width. height.

Parameters:

height width - the height width of the invisible component, in pixels >= 0

Returns:

the component

See Also:

createHorizontalStrut(int) createVerticalStrut(int) , createGlue() , createRigidArea(java.awt.Dimension)

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createGlue createVerticalStrut

public static ComponentcreateGlue createVerticalStrut () (int height) 

Creates an invisible "glue" component that can be useful in a Box whose visible components have a maximum width (for a horizontal box) or height (for a vertical box). You can think of the glue component as being a gooey substance that expands as much as necessary to fill the space between its neighboring components. Creates an invisible, fixed-height component. In a vertical box, you typically use this method to force a certain amount of space between two components. In a horizontal box, you might use this method to force the box to be at least the specified height. The invisible component has no width unless excess space is available, in which case it takes its share of available space, just like any other component that has no maximum width.

For example, suppose you have a horizontal box that contains two fixed-size components. If the box gets extra space, the fixed-size components won't become larger, so where does the extra space go? Without glue, the extra space goes to the right of the second component. If you put glue between the fixed-size components, then the extra space goes there. If you put glue before the first fixed-size component, the extra space goes there, and the fixed-size components are shoved against the right edge of the box. If you put glue before the first fixed-size component and after the second fixed-size component, the fixed-size components are centered in the box.

To use glue, call Box.createGlue and add the returned component to a container. The glue component has no minimum or preferred size, so it takes no space unless excess space is available. If excess space is available, then the glue component takes its share of available horizontal or vertical space, just like any other component that has no maximum width or height.

Parameters:

height - the height of the invisible component, in pixels >= 0

Returns:

the component

See Also:

createHorizontalStrut(int) , createGlue() , createRigidArea(java.awt.Dimension)

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createHorizontalGlue createGlue

public static ComponentcreateHorizontalGlue createGlue ()

Creates a horizontal glue component. Creates an invisible "glue" component that can be useful in a Box whose visible components have a maximum width (for a horizontal box) or height (for a vertical box). You can think of the glue component as being a gooey substance that expands as much as necessary to fill the space between its neighboring components.

For example, suppose you have a horizontal box that contains two fixed-size components. If the box gets extra space, the fixed-size components won't become larger, so where does the extra space go? Without glue, the extra space goes to the right of the second component. If you put glue between the fixed-size components, then the extra space goes there. If you put glue before the first fixed-size component, the extra space goes there, and the fixed-size components are shoved against the right edge of the box. If you put glue before the first fixed-size component and after the second fixed-size component, the fixed-size components are centered in the box.

To use glue, call Box.createGlue and add the returned component to a container. The glue component has no minimum or preferred size, so it takes no space unless excess space is available. If excess space is available, then the glue component takes its share of available horizontal or vertical space, just like any other component that has no maximum width or height.

Returns:

the component

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createVerticalGlue createHorizontalGlue

public static ComponentcreateVerticalGlue createHorizontalGlue ()

Creates a vertical horizontal glue component.

Returns:

the component

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setLayout createVerticalGlue

public void 
public static ComponentsetLayout createVerticalGlue ( LayoutManager l) () 

Throws an AWTError, since a Box can use only a BoxLayout. Creates a vertical glue component.

Overrides:

setLayout in class Container

Parameters: Returns:

l - the layout manager to use

See Also:

Container.doLayout() , Container.getLayout() the component

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paintComponent setLayout

protected 
public void paintComponent setLayout ( GraphicsLayoutManager g)  l) 

Paints this Box. If this Box has a UI this method invokes super's implementation, otherwise if this Box is opaque the Graphics is filled using the background. Throws an AWTError, since a Box can use only a BoxLayout.

Overrides:

paintComponent setLayout in class JComponent Container

Parameters:

g - the Graphics to paint to l - the layout manager to use

Throws:

NullPointerException - if g is null

Since:

1.6

See Also:

JComponent.paint(java.awt.Graphics) Container.doLayout() , ComponentUI Container.getLayout()

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getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this Box. For boxes, the AccessibleContext takes the form of an AccessibleBox. A new AccessibleAWTBox instance is created if necessary.

Specified by:

getAccessibleContext in interface Accessible

Overrides:

getAccessibleContext in class JComponent

Returns:

an AccessibleBox that serves as the AccessibleContext of this Box

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