/*******************************************************************************
* Copyright (c) 2000, 2016 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.accessibility;
/**
* This adapter class provides default implementations for the
* methods described by the AccessibleControlListener interface.
*
* Classes that wish to deal with AccessibleControlEvents can
* extend this class and override only the methods that they are
* interested in.
*
* 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.
* When returning a child identifier to a client, you may use CHILDID_NONE
* to indicate that no child or control has the required information.
*
* Note: This adapter is typically used by implementors of
* a custom control to provide very detailed information about
* the control instance to accessibility clients.
*
*
* @see AccessibleControlListener
* @see AccessibleControlEvent
* @see Sample code and further information
*
* @since 2.0
*/
public abstract class AccessibleControlAdapter implements AccessibleControlListener {
/**
* Sent when an accessibility client requests the identifier
* of the control child at the specified display coordinates.
* The default behavior is to do nothing.
*
* Return the identifier of the child at display point (x, y)
* in the childID field of the event object.
* Return CHILDID_SELF if point (x, y) is in the control itself
* and not in any child. Return CHILDID_NONE if point (x, y)
* is not contained in either the control or any of its children.
*
*
* @param e an event object containing the following fields:
* - x, y [IN] - the specified point in display coordinates
* - childID [Typical OUT] - the ID of the child at point, or CHILDID_SELF, or CHILDID_NONE
* - accessible [Optional OUT] - the accessible object for the control or child may be returned instead of the childID
*
*/
@Override
public void getChildAtPoint(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the location
* of the control, or the location of a child of the control.
* The default behavior is to do nothing.
*
* Return a rectangle describing the location of the specified
* control or child in the x, y, width, and height
* fields of the event object.
*
*
* @param e an event object containing the following fields:
* - childID [IN] - an identifier specifying the control or one of its children
* - x, y, width, height [OUT] - the control or child location in display coordinates
*
*/
@Override
public void getLocation(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the accessible object
* for a child of the control by index or childID, or when a client
* requests the index of an accessible object in its parent.
*
* The childID field in the event object can be one of the following:
*
* - an integer child ID - return the accessible object for the specified child ID,
* or null if the specified child does not have its own accessible
* - {@link ACC#CHILDID_CHILD_AT_INDEX} - return the accessible child object at the specified index,
* or null if this object has no children
* - {@link ACC#CHILDID_CHILD_INDEX} - return the index of this accessible in its parent
*
*
* @param e an event object containing the following fields:
* - childID [IN] - an identifier specifying a child of the control, or one of the predefined CHILDID constants
* - detail [Optional IN] - the index of the child accessible to be returned when childID = CHILDID_CHILD_AT_INDEX
* - detail [Optional OUT] - the index of this accessible in its parent when childID = CHILDID_CHILD_INDEX
* - accessible [Optional OUT] - an Accessible for the specified childID or index, or null if one does not exist
*
*/
@Override
public void getChild(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the number of
* children in the control.
* The default behavior is to do nothing.
*
* Return the number of child items in the detail
* field of the event object.
*
*
* @param e an event object containing the following fields:
* - detail [OUT] - the number of child items in this control
*
*/
@Override
public void getChildCount(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the default action
* of the control, or the default action of a child of the control.
* The default behavior is to do nothing.
*
* This string is typically a verb describing what the user does to it.
* For example, a Push Button's default action is "Press", a Check Button's
* is "Check" or "UnCheck", and List items have the default action "Double Click".
*
* Return a string describing the default action of the specified
* control or child in the result field of the event object.
* Returning null tells the client to use the platform default action string.
*
*
* @param e an event object containing the following fields:
* - childID [IN] - an identifier specifying the control or one of its children
* - result [OUT] - the requested default action string, or null
*
*/
@Override
public void getDefaultAction(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the identity of
* the child or control that has keyboard focus.
* The default behavior is to do nothing.
*
* Return the identifier of the child that has focus in the
* childID field of the event object.
* Return CHILDID_SELF if the control itself has keyboard focus.
* Return CHILDID_NONE if neither the control nor any of its children has focus.
*
*
* @param e an event object containing the following fields:
* - childID [Typical OUT] - the ID of the child with focus, or CHILDID_SELF, or CHILDID_NONE
* - accessible [Optional OUT] - the accessible object for a child may be returned instead of its childID
*
*/
@Override
public void getFocus(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the role
* of the control, or the role of a child of the control.
* The default behavior is to do nothing.
*
* Return a role constant (constant defined in ACC beginning with ROLE_)
* that describes the role of the specified control or child in the
* detail field of the event object.
*
*
* @param e an event object containing the following fields:
* - childID [IN] - an identifier specifying the control or one of its children
* - detail [OUT] - a role constant describing the role of the control or child
*
*/
@Override
public void getRole(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the identity of
* the child or control that is currently selected.
* The default behavior is to do nothing.
*
* Return the identifier of the selected child in the
* childID field of the event object.
* Return CHILDID_SELF if the control itself is selected.
* Return CHILDID_MULTIPLE if multiple children are selected, and return an array of childIDs in the children field.
* Return CHILDID_NONE if neither the control nor any of its children are selected.
*
*
* @param e an event object containing the following fields:
* - childID [Typical OUT] - the ID of the selected child, or CHILDID_SELF, or CHILDID_MULTIPLE, or CHILDID_NONE
* - children [Optional OUT] - the array of childIDs for the selected children if CHILDID_MULTIPLE is returned
* - accessible [Optional OUT] - the accessible object for the control or child may be returned instead of the childID
*
*/
@Override
public void getSelection(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the state
* of the control, or the state of a child of the control.
* The default behavior is to do nothing.
*
* Return a state mask (mask bit constants defined in ACC beginning with STATE_)
* that describes the current state of the specified control or child in the
* detail field of the event object.
*
*
* @param e an event object containing the following fields:
* - childID [IN] - an identifier specifying the control or one of its children
* - detail [OUT] - a state mask describing the current state of the control or child
*
*/
@Override
public void getState(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the value
* of the control, or the value of a child of the control.
* The default behavior is to do nothing.
*
* Many controls do not return a value. Examples of controls
* that do are: Combo returns the text string, Text returns
* its contents, ProgressBar returns a string representing a
* percentage, and Tree items return a string representing
* their level in the tree.
*
* Return a string describing the value of the specified control
* or child in the result field of the event object.
* Returning null tells the client to use the platform value string.
*
*
* @param e an event object containing the following fields:
* - childID [IN] - an identifier specifying the control or one of its children
* - result [OUT] - the requested value string, or null
*
*/
@Override
public void getValue(AccessibleControlEvent e) {
}
/**
* Sent when an accessibility client requests the children, or visible children,
* of the control. The default behavior is to do nothing.
*
* Return the children as an array of childIDs or accessibles in the
* children field of the event object.
*
*
* @param e an event object containing the following fields:
* - detail [IN] - a flag that may have one of the following values:
* - 0 (default) - return all children
* - VISIBLE - return all visible children
*
* - children [Typical OUT] - an array of childIDs
* - children [Optional OUT] - an array of accessible objects for the children may be returned instead of the childIDs
*
*/
@Override
public void getChildren(AccessibleControlEvent e) {
}
}