1. /*

  2.  * @(#)AccessibleComponent.java	1.16 03/12/19

  3.  *

  4.  * Copyright 2004 Sun Microsystems, Inc. All rights reserved.

  5.  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.

  6.  */

  7. 

  8. package javax.accessibility;

  9. 

  10. import java.awt.*;

  11. import java.awt.event.*;

  12. 

  13. /**

  14.  * The AccessibleComponent interface should be supported by any object 

  15.  * that is rendered on the screen.  This interface provides the standard 

  16.  * mechanism for an assistive technology to determine and set the 

  17.  * graphical representation of an object.  Applications can determine

  18.  * if an object supports the AccessibleComponent interface by first

  19.  * obtaining its AccessibleContext 

  20.  * and then calling the

  21.  * {@link AccessibleContext#getAccessibleComponent} method.

  22.  * If the return value is not null, the object supports this interface.

  23.  *

  24.  * @see Accessible

  25.  * @see Accessible#getAccessibleContext

  26.  * @see AccessibleContext

  27.  * @see AccessibleContext#getAccessibleComponent

  28.  *

  29.  * @version     1.7 10/05/99 14:00:28

  30.  * @author	Peter Korn

  31.  * @author	Hans Muller

  32.  * @author      Willie Walker

  33.  */

  34. public interface AccessibleComponent {

  35. 

  36.     /**

  37.      * Gets the background color of this object.

  38.      *

  39.      * @return the background color, if supported, of the object; 

  40.      * otherwise, null

  41.      * @see #setBackground

  42.      */

  43.     public Color getBackground();

  44. 

  45.     /**

  46.      * Sets the background color of this object.

  47.      *

  48.      * @param c the new Color for the background

  49.      * @see #setBackground

  50.      */

  51.     public void setBackground(Color c);

  52. 

  53.     /**

  54.      * Gets the foreground color of this object.

  55.      *

  56.      * @return the foreground color, if supported, of the object; 

  57.      * otherwise, null

  58.      * @see #setForeground

  59.      */

  60.     public Color getForeground();

  61. 

  62.     /**

  63.      * Sets the foreground color of this object.

  64.      *

  65.      * @param c the new Color for the foreground

  66.      * @see #getForeground

  67.      */

  68.     public void setForeground(Color c);

  69. 

  70.     /**

  71.      * Gets the Cursor of this object.

  72.      *

  73.      * @return the Cursor, if supported, of the object; otherwise, null

  74.      * @see #setCursor

  75.      */

  76.     public Cursor getCursor();

  77. 

  78.     /**

  79.      * Sets the Cursor of this object.

  80.      *

  81.      * @param cursor  the new Cursor for the object

  82.      * @see #getCursor

  83.      */

  84.     public void setCursor(Cursor cursor);

  85. 

  86.     /**

  87.      * Gets the Font of this object.

  88.      *

  89.      * @return the Font,if supported, for the object; otherwise, null

  90.      * @see #setFont

  91.      */

  92.     public Font getFont();

  93. 

  94.     /**

  95.      * Sets the Font of this object.

  96.      *

  97.      * @param f the new Font for the object

  98.      * @see #getFont

  99.      */

  100.     public void setFont(Font f);

  101. 

  102.     /**

  103.      * Gets the FontMetrics of this object.

  104.      *

  105.      * @param f the Font

  106.      * @return the FontMetrics, if supported, the object; otherwise, null

  107.      * @see #getFont

  108.      */

  109.     public FontMetrics getFontMetrics(Font f);

  110. 

  111.     /**

  112.      * Determines if the object is enabled.  Objects that are enabled

  113.      * will also have the AccessibleState.ENABLED state set in their

  114.      * AccessibleStateSets.

  115.      *

  116.      * @return true if object is enabled; otherwise, false

  117.      * @see #setEnabled

  118.      * @see AccessibleContext#getAccessibleStateSet

  119.      * @see AccessibleState#ENABLED

  120.      * @see AccessibleStateSet

  121.      */

  122.     public boolean isEnabled();

  123. 

  124.     /**

  125.      * Sets the enabled state of the object.

  126.      *

  127.      * @param b if true, enables this object; otherwise, disables it 

  128.      * @see #isEnabled

  129.      */

  130.     public void setEnabled(boolean b);

  131. 

  132.     /**

  133.      * Determines if the object is visible.  Note: this means that the

  134.      * object intends to be visible; however, it may not be

  135.      * showing on the screen because one of the objects that this object

  136.      * is contained by is currently not visible.  To determine if an object is

  137.      * showing on the screen, use isShowing().

  138.      * <p>Objects that are visible will also have the 

  139.      * AccessibleState.VISIBLE state set in their AccessibleStateSets.

  140.      *

  141.      * @return true if object is visible; otherwise, false

  142.      * @see #setVisible

  143.      * @see AccessibleContext#getAccessibleStateSet

  144.      * @see AccessibleState#VISIBLE

  145.      * @see AccessibleStateSet

  146.      */

  147.     public boolean isVisible();

  148. 

  149.     /**

  150.      * Sets the visible state of the object.

  151.      *

  152.      * @param b if true, shows this object; otherwise, hides it 

  153.      * @see #isVisible

  154.      */

  155.     public void setVisible(boolean b);

  156. 

  157.     /**

  158.      * Determines if the object is showing.  This is determined by checking

  159.      * the visibility of the object and its ancestors.

  160.      * Note: this

  161.      * will return true even if the object is obscured by another (for example,

  162.      * it is underneath a menu that was pulled down).

  163.      *

  164.      * @return true if object is showing; otherwise, false

  165.      */

  166.     public boolean isShowing();

  167. 

  168.     /** 

  169.      * Checks whether the specified point is within this object's bounds,

  170.      * where the point's x and y coordinates are defined to be relative to the

  171.      * coordinate system of the object. 

  172.      *

  173.      * @param p the Point relative to the coordinate system of the object

  174.      * @return true if object contains Point; otherwise false

  175.      * @see #getBounds

  176.      */

  177.     public boolean contains(Point p);

  178. 

  179.     /** 

  180.      * Returns the location of the object on the screen.

  181.      *

  182.      * @return the location of the object on screen; null if this object

  183.      * is not on the screen

  184.      * @see #getBounds

  185.      * @see #getLocation

  186.      */

  187.     public Point getLocationOnScreen();

  188. 

  189.     /** 

  190.      * Gets the location of the object relative to the parent in the form 

  191.      * of a point specifying the object's top-left corner in the screen's 

  192.      * coordinate space.

  193.      *

  194.      * @return An instance of Point representing the top-left corner of the 

  195.      * object's bounds in the coordinate space of the screen; null if

  196.      * this object or its parent are not on the screen

  197.      * @see #getBounds

  198.      * @see #getLocationOnScreen

  199.      */

  200.     public Point getLocation();

  201. 

  202.     /** 

  203.      * Sets the location of the object relative to the parent.

  204.      * @param p the new position for the top-left corner

  205.      * @see #getLocation

  206.      */

  207.     public void setLocation(Point p);

  208. 

  209.     /** 

  210.      * Gets the bounds of this object in the form of a Rectangle object. 

  211.      * The bounds specify this object's width, height, and location

  212.      * relative to its parent. 

  213.      *

  214.      * @return A rectangle indicating this component's bounds; null if 

  215.      * this object is not on the screen.

  216.      * @see #contains

  217.      */

  218.     public Rectangle getBounds();

  219. 

  220.     /** 

  221.      * Sets the bounds of this object in the form of a Rectangle object. 

  222.      * The bounds specify this object's width, height, and location

  223.      * relative to its parent.

  224.      *	

  225.      * @param r rectangle indicating this component's bounds

  226.      * @see #getBounds

  227.      */

  228.     public void setBounds(Rectangle r);

  229. 

  230.     /** 

  231.      * Returns the size of this object in the form of a Dimension object. 

  232.      * The height field of the Dimension object contains this object's

  233.      * height, and the width field of the Dimension object contains this 

  234.      * object's width. 

  235.      *

  236.      * @return A Dimension object that indicates the size of this component; 

  237.      * null if this object is not on the screen

  238.      * @see #setSize

  239.      */

  240.     public Dimension getSize();

  241. 

  242.     /** 

  243.      * Resizes this object so that it has width and height. 

  244.      *	

  245.      * @param d The dimension specifying the new size of the object. 

  246.      * @see #getSize

  247.      */

  248.     public void setSize(Dimension d);

  249. 

  250.     /**

  251.      * Returns the Accessible child, if one exists, contained at the local 

  252.      * coordinate Point.

  253.      *

  254.      * @param p The point relative to the coordinate system of this object.

  255.      * @return the Accessible, if it exists, at the specified location; 

  256.      * otherwise null

  257.      */

  258.     public Accessible getAccessibleAt(Point p);

  259. 

  260.     /**

  261.      * Returns whether this object can accept focus or not.   Objects that 

  262.      * can accept focus will also have the AccessibleState.FOCUSABLE state 

  263.      * set in their AccessibleStateSets.

  264.      *

  265.      * @return true if object can accept focus; otherwise false

  266.      * @see AccessibleContext#getAccessibleStateSet

  267.      * @see AccessibleState#FOCUSABLE

  268.      * @see AccessibleState#FOCUSED

  269.      * @see AccessibleStateSet

  270.      */

  271.     public boolean isFocusTraversable();

  272. 

  273.     /**

  274.      * Requests focus for this object.  If this object cannot accept focus,

  275.      * nothing will happen.  Otherwise, the object will attempt to take

  276.      * focus.

  277.      * @see #isFocusTraversable

  278.      */

  279.     public void requestFocus();

  280. 

  281.     /**

  282.      * Adds the specified focus listener to receive focus events from this 

  283.      * component. 

  284.      *

  285.      * @param l the focus listener

  286.      * @see #removeFocusListener

  287.      */

  288.     public void addFocusListener(FocusListener l);

  289. 

  290.     /**

  291.      * Removes the specified focus listener so it no longer receives focus 

  292.      * events from this component.

  293.      *

  294.      * @param l the focus listener

  295.      * @see #addFocusListener

  296.      */

  297.     public void removeFocusListener(FocusListener l);

  298. }