JavaTM 2 Platform
Std. Ed. v1.4.1

javax.accessibility
Interface AccessibleComponent

All Known Subinterfaces:
AccessibleExtendedComponent
All Known Implementing Classes:
AbstractButton.AccessibleAbstractButton, Component.AccessibleAWTComponent, JComponent.AccessibleJComponent, JLabel.AccessibleJLabel, JList.AccessibleJList.AccessibleJListChild, JTable.AccessibleJTable.AccessibleJTableCell, JTableHeader.AccessibleJTableHeader.AccessibleJTableHeaderEntry, JTree.AccessibleJTree.AccessibleJTreeNode, MenuComponent.AccessibleAWTMenuComponent

public interface AccessibleComponent

The AccessibleComponent interface should be supported by any object that is rendered on the screen. This interface provides the standard mechanism for an assistive technology to determine and set the graphical representation of an object. Applications can determine if an object supports the AccessibleComponent interface by first obtaining its AccessibleContext and then calling the AccessibleContext.getAccessibleComponent() method. If the return value is not null, the object supports this interface.

See Also:
Accessible, Accessible.getAccessibleContext(), AccessibleContext, AccessibleContext.getAccessibleComponent()

Method Summary
 void addFocusListener(FocusListener l)
          Adds the specified focus listener to receive focus events from this component.
 boolean contains(Point p)
          Checks whether the specified point is within this object's bounds, where the point's x and y coordinates are defined to be relative to the coordinate system of the object.
 Accessible getAccessibleAt(Point p)
          Returns the Accessible child, if one exists, contained at the local coordinate Point.
 Color getBackground()
          Gets the background color of this object.
 Rectangle getBounds()
          Gets the bounds of this object in the form of a Rectangle object.
 Cursor getCursor()
          Gets the Cursor of this object.
 Font getFont()
          Gets the Font of this object.
 FontMetrics getFontMetrics(Font f)
          Gets the FontMetrics of this object.
 Color getForeground()
          Gets the foreground color of this object.
 Point getLocation()
          Gets the location of the object relative to the parent in the form of a point specifying the object's top-left corner in the screen's coordinate space.
 Point getLocationOnScreen()
          Returns the location of the object on the screen.
 Dimension getSize()
          Returns the size of this object in the form of a Dimension object.
 boolean isEnabled()
          Determines if the object is enabled.
 boolean isFocusTraversable()
          Returns whether this object can accept focus or not.
 boolean isShowing()
          Determines if the object is showing.
 boolean isVisible()
          Determines if the object is visible.
 void removeFocusListener(FocusListener l)
          Removes the specified focus listener so it no longer receives focus events from this component.
 void requestFocus()
          Requests focus for this object.
 void setBackground(Color c)
          Sets the background color of this object.
 void setBounds(Rectangle r)
          Sets the bounds of this object in the form of a Rectangle object.
 void setCursor(Cursor cursor)
          Sets the Cursor of this object.
 void setEnabled(boolean b)
          Sets the enabled state of the object.
 void setFont(Font f)
          Sets the Font of this object.
 void setForeground(Color c)
          Sets the foreground color of this object.
 void setLocation(Point p)
          Sets the location of the object relative to the parent.
 void setSize(Dimension d)
          Resizes this object so that it has width and height.
 void setVisible(boolean b)
          Sets the visible state of the object.
 

Method Detail

getBackground

public Color getBackground()
Gets the background color of this object.

Returns:
the background color, if supported, of the object; otherwise, null
See Also:
setBackground(java.awt.Color)

setBackground

public void setBackground(Color c)
Sets the background color of this object.

Parameters:
c - the new Color for the background
See Also:
setBackground(java.awt.Color)

getForeground

public Color getForeground()
Gets the foreground color of this object.

Returns:
the foreground color, if supported, of the object; otherwise, null
See Also:
setForeground(java.awt.Color)

setForeground

public void setForeground(Color c)
Sets the foreground color of this object.

Parameters:
c - the new Color for the foreground
See Also:
getForeground()

getCursor

public Cursor getCursor()
Gets the Cursor of this object.

Returns:
the Cursor, if supported, of the object; otherwise, null
See Also:
setCursor(java.awt.Cursor)

setCursor

public void setCursor(Cursor cursor)
Sets the Cursor of this object.

See Also:
getCursor()

getFont

public Font getFont()
Gets the Font of this object.

Returns:
the Font,if supported, for the object; otherwise, null
See Also:
setFont(java.awt.Font)

setFont

public void setFont(Font f)
Sets the Font of this object.

Parameters:
f - the new Font for the object
See Also:
getFont()

getFontMetrics

public FontMetrics getFontMetrics(Font f)
Gets the FontMetrics of this object.

Parameters:
f - the Font
Returns:
the FontMetrics, if supported, the object; otherwise, null
See Also:
getFont()

isEnabled

public boolean isEnabled()
Determines if the object is enabled. Objects that are enabled will also have the AccessibleState.ENABLED state set in their AccessibleStateSets.

Returns:
true if object is enabled; otherwise, false
See Also:
setEnabled(boolean), AccessibleContext.getAccessibleStateSet(), AccessibleState.ENABLED, AccessibleStateSet

setEnabled

public void setEnabled(boolean b)
Sets the enabled state of the object.

Parameters:
b - if true, enables this object; otherwise, disables it
See Also:
isEnabled()

isVisible

public boolean isVisible()
Determines if the object is visible. Note: this means that the object intends to be visible; however, it may not be showing on the screen because one of the objects that this object is contained by is currently not visible. To determine if an object is showing on the screen, use isShowing().

Objects that are visible will also have the AccessibleState.VISIBLE state set in their AccessibleStateSets.

Returns:
true if object is visible; otherwise, false
See Also:
setVisible(boolean), AccessibleContext.getAccessibleStateSet(), AccessibleState.VISIBLE, AccessibleStateSet

setVisible

public void setVisible(boolean b)
Sets the visible state of the object.

Parameters:
b - if true, shows this object; otherwise, hides it
See Also:
isVisible()

isShowing

public boolean isShowing()
Determines if the object is showing. This is determined by checking the visibility of the object and its ancestors. Note: this will return true even if the object is obscured by another (for example, it is underneath a menu that was pulled down).

Returns:
true if object is showing; otherwise, false

contains

public boolean contains(Point p)
Checks whether the specified point is within this object's bounds, where the point's x and y coordinates are defined to be relative to the coordinate system of the object.

Parameters:
p - the Point relative to the coordinate system of the object
Returns:
true if object contains Point; otherwise false
See Also:
getBounds()

getLocationOnScreen

public Point getLocationOnScreen()
Returns the location of the object on the screen.

Returns:
the location of the object on screen; null if this object is not on the screen
See Also:
getBounds(), getLocation()

getLocation

public Point getLocation()
Gets the location of the object relative to the parent in the form of a point specifying the object's top-left corner in the screen's coordinate space.

Returns:
An instance of Point representing the top-left corner of the object's bounds in the coordinate space of the screen; null if this object or its parent are not on the screen
See Also:
getBounds(), getLocationOnScreen()

setLocation

public void setLocation(Point p)
Sets the location of the object relative to the parent.

Parameters:
p - the new position for the top-left corner
See Also:
getLocation()

getBounds

public Rectangle getBounds()
Gets the bounds of this object in the form of a Rectangle object. The bounds specify this object's width, height, and location relative to its parent.

Returns:
A rectangle indicating this component's bounds; null if this object is not on the screen.
See Also:
contains(java.awt.Point)

setBounds

public void setBounds(Rectangle r)
Sets the bounds of this object in the form of a Rectangle object. The bounds specify this object's width, height, and location relative to its parent.

Parameters:
r - rectangle indicating this component's bounds
See Also:
getBounds()

getSize

public Dimension getSize()
Returns the size of this object in the form of a Dimension object. The height field of the Dimension object contains this object's height, and the width field of the Dimension object contains this object's width.

Returns:
A Dimension object that indicates the size of this component; null if this object is not on the screen
See Also:
setSize(java.awt.Dimension)

setSize

public void setSize(Dimension d)
Resizes this object so that it has width and height.

Parameters:
d - The dimension specifying the new size of the object.
See Also:
getSize()

getAccessibleAt

public Accessible getAccessibleAt(Point p)
Returns the Accessible child, if one exists, contained at the local coordinate Point.

Parameters:
p - The point relative to the coordinate system of this object.
Returns:
the Accessible, if it exists, at the specified location; otherwise null

isFocusTraversable

public boolean isFocusTraversable()
Returns whether this object can accept focus or not. Objects that can accept focus will also have the AccessibleState.FOCUSABLE state set in their AccessibleStateSets.

Returns:
true if object can accept focus; otherwise false
See Also:
AccessibleContext.getAccessibleStateSet(), AccessibleState.FOCUSABLE, AccessibleState.FOCUSED, AccessibleStateSet

requestFocus

public void requestFocus()
Requests focus for this object. If this object cannot accept focus, nothing will happen. Otherwise, the object will attempt to take focus.

See Also:
isFocusTraversable()

addFocusListener

public void addFocusListener(FocusListener l)
Adds the specified focus listener to receive focus events from this component.

Parameters:
l - the focus listener
See Also:
removeFocusListener(java.awt.event.FocusListener)

removeFocusListener

public void removeFocusListener(FocusListener l)
Removes the specified focus listener so it no longer receives focus events from this component.

Parameters:
l - the focus listener
See Also:
addFocusListener(java.awt.event.FocusListener)

JavaTM 2 Platform
Std. Ed. v1.4.1

Submit a bug or feature
For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2002 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.