/*******************************************************************************
* Copyright (c) 2000, 2005 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.accessibility;
import org.eclipse.swt.internal.SWTEventListener;
/**
* Classes that implement this interface provide methods
* that deal with the events that are generated when an
* accessibility client sends a message to a control.
* <p>
* After creating an instance of a class that implements
* this interface it can be added to a control using the
* <code>addAccessibleListener</code> method and removed
* using the <code>removeAccessibleListener</code> method.
* When a client requests information, the appropriate method
* will be invoked.
* </p><p>
* Note: Accessibility clients use child identifiers to specify
* whether they want information about a control or one of its children.
* Child identifiers are increasing integers beginning with 0.
* The identifier CHILDID_SELF represents the control itself.
* </p>
*
* @see AccessibleAdapter
* @see AccessibleEvent
*
* @since 1.4
*/
public interface AccessibleListener extends SWTEventListener {
/**
* Sent when an accessibility client requests the name
* of the control, or the name of a child of the control.
* <p>
* Return the name of the control or specified child in the
* <code>result</code> field of the event object. Returning
* an empty string tells the client that the control or child
* does not have a name, and returning null tells the client
* to use the platform name.
* </p>
*
* @param e an event object containing the following fields:<ul>
* <li>childID [IN] - an identifier specifying the control or one of its children</li>
* <li>result [OUT] - the requested name string, or null</li>
* </ul>
*/
public void getName(AccessibleEvent e);
/**
* Sent when an accessibility client requests the help string
* of the control, or the help string of a child of the control.
* <p>
* The information in this property should be similar to the help
* provided by toolTipText. It describes what the control or child
* does or how to use it, as opposed to getDescription, which
* describes appearance.
* </p><p>
* Return the help string of the control or specified child in
* the <code>result</code> field of the event object. Returning
* an empty string tells the client that the control or child
* does not have a help string, and returning null tells the
* client to use the platform help string.
* </p>
*
* @param e an event object containing the following fields:<ul>
* <li>childID [IN] - an identifier specifying the control or one of its children</li>
* <li>result [OUT] - the requested help string, or null</li>
* </ul>
*/
public void getHelp(AccessibleEvent e);
/**
* Sent when an accessibility client requests the keyboard shortcut
* of the control, or the keyboard shortcut of a child of the control.
* <p>
* A keyboard shortcut can either be a mnemonic, or an accelerator.
* As a general rule, if the control or child can receive keyboard focus,
* then you should expose its mnemonic, and if it cannot receive keyboard
* focus, then you should expose its accelerator.
* </p><p>
* Return the keyboard shortcut string of the control or specified child
* in the <code>result</code> field of the event object. Returning an
* empty string tells the client that the control or child does not
* have a keyboard shortcut string, and returning null tells the client
* to use the platform keyboard shortcut string.
* </p>
*
* @param e an event object containing the following fields:<ul>
* <li>childID [IN] - an identifier specifying the control or one of its children</li>
* <li>result [OUT] - the requested keyboard shortcut string (example: "ALT+N"), or null</li>
* </ul>
*/
public void getKeyboardShortcut(AccessibleEvent e);
/**
* Sent when an accessibility client requests a description
* of the control, or a description of a child of the control.
* <p>
* This is a textual description of the control or child's visual
* appearance, which is typically only necessary if it cannot be
* determined from other properties such as role.
* </p><p>
* Return the description of the control or specified child in
* the <code>result</code> field of the event object. Returning
* an empty string tells the client that the control or child
* does not have a description, and returning null tells the
* client to use the platform description.
* </p>
*
* @param e an event object containing the following fields:<ul>
* <li>childID [IN] - an identifier specifying the control or one of its children</li>
* <li>result [OUT] - the requested description string, or null</li>
* </ul>
*/
public void getDescription(AccessibleEvent e);
}