Java™ Platform
Standard Ed. 8
javax.accessibility

Class AccessibleContext

  • Direct Known Subclasses:
    Component.AccessibleAWTComponent, ImageIcon.AccessibleImageIcon, JList.AccessibleJList.AccessibleJListChild, JTable.AccessibleJTable.AccessibleJTableCell, JTableHeader.AccessibleJTableHeader.AccessibleJTableHeaderEntry, JTree.AccessibleJTree.AccessibleJTreeNode, MenuComponent.AccessibleAWTMenuComponent, ProgressMonitor.AccessibleProgressMonitor


    public abstract class AccessibleContext
    extends Object
    AccessibleContext represents the minimum information all accessible objects return. This information includes the accessible name, description, role, and state of the object, as well as information about its parent and children. AccessibleContext also contains methods for obtaining more specific accessibility information about a component. If the component supports them, these methods will return an object that implements one or more of the following interfaces:

    • AccessibleAction - the object can perform one or more actions. This interface provides the standard mechanism for an assistive technology to determine what those actions are and tell the object to perform them. Any object that can be manipulated should support this interface.
    • AccessibleComponent - the object has a graphical representation. This interface provides the standard mechanism for an assistive technology to determine and set the graphical representation of the object. Any object that is rendered on the screen should support this interface.
    • AccessibleSelection - the object allows its children to be selected. This interface provides the standard mechanism for an assistive technology to determine the currently selected children of the object as well as modify its selection set. Any object that has children that can be selected should support this interface.
    • AccessibleText - the object presents editable textual information on the display. This interface provides the standard mechanism for an assistive technology to access that text via its content, attributes, and spatial location. Any object that contains editable text should support this interface.
    • AccessibleValue - the object supports a numerical value. This interface provides the standard mechanism for an assistive technology to determine and set the current value of the object, as well as obtain its minimum and maximum values. Any object that supports a numerical value should support this interface.
    • Field Detail

      • ACCESSIBLE_STATE_PROPERTY

        public static final String ACCESSIBLE_STATE_PROPERTY
        Constant used to determine when the accessibleStateSet property has changed. The old value will be the old AccessibleState and the new value will be the new AccessibleState in the accessibleStateSet. For example, if a component that supports the vertical and horizontal states changes its orientation from vertical to horizontal, the old value will be AccessibleState.VERTICAL and the new value will be AccessibleState.HORIZONTAL. Please note that either value can also be null. For example, when a component changes from being enabled to disabled, the old value will be AccessibleState.ENABLED and the new value will be null.
        See Also:
        getAccessibleStateSet(), AccessibleState, AccessibleStateSet, addPropertyChangeListener(java.beans.PropertyChangeListener), Constant Field Values
      • ACCESSIBLE_CHILD_PROPERTY

        public static final String ACCESSIBLE_CHILD_PROPERTY
        Constant used to determine when Accessible children are added/removed from the object. If an Accessible child is being added, the old value will be null and the new value will be the Accessible child. If an Accessible child is being removed, the old value will be the Accessible child, and the new value will be null.
        See Also:
        addPropertyChangeListener(java.beans.PropertyChangeListener), Constant Field Values
      • ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY

        public static final String ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY
        Constant used to determine when the active descendant of a component has changed. The active descendant is used for objects such as list, tree, and table, which may have transient children. When the active descendant has changed, the old value of the property change event will be the Accessible representing the previous active child, and the new value will be the Accessible representing the current active child.
        See Also:
        addPropertyChangeListener(java.beans.PropertyChangeListener), Constant Field Values
      • ACCESSIBLE_TABLE_CAPTION_CHANGED

        public static final String ACCESSIBLE_TABLE_CAPTION_CHANGED
        Constant used to indicate that the table caption has changed The old value in the PropertyChangeEvent will be an Accessible representing the previous table caption and the new value will be an Accessible representing the new table caption.
        See Also:
        Accessible, AccessibleTable, Constant Field Values
      • ACCESSIBLE_TABLE_SUMMARY_CHANGED

        public static final String ACCESSIBLE_TABLE_SUMMARY_CHANGED
        Constant used to indicate that the table summary has changed The old value in the PropertyChangeEvent will be an Accessible representing the previous table summary and the new value will be an Accessible representing the new table summary.
        See Also:
        Accessible, AccessibleTable, Constant Field Values
      • ACCESSIBLE_TABLE_MODEL_CHANGED

        public static final String ACCESSIBLE_TABLE_MODEL_CHANGED
        Constant used to indicate that table data has changed. The old value in the PropertyChangeEvent will be null and the new value will be an AccessibleTableModelChange representing the table change.
        See Also:
        AccessibleTable, AccessibleTableModelChange, Constant Field Values
      • ACCESSIBLE_TABLE_ROW_HEADER_CHANGED

        public static final String ACCESSIBLE_TABLE_ROW_HEADER_CHANGED
        Constant used to indicate that the row header has changed The old value in the PropertyChangeEvent will be null and the new value will be an AccessibleTableModelChange representing the header change.
        See Also:
        AccessibleTable, AccessibleTableModelChange, Constant Field Values
      • ACCESSIBLE_TABLE_ROW_DESCRIPTION_CHANGED

        public static final String ACCESSIBLE_TABLE_ROW_DESCRIPTION_CHANGED
        Constant used to indicate that the row description has changed The old value in the PropertyChangeEvent will be null and the new value will be an Integer representing the row index.
        See Also:
        AccessibleTable, Constant Field Values
      • ACCESSIBLE_TABLE_COLUMN_HEADER_CHANGED

        public static final String ACCESSIBLE_TABLE_COLUMN_HEADER_CHANGED
        Constant used to indicate that the column header has changed The old value in the PropertyChangeEvent will be null and the new value will be an AccessibleTableModelChange representing the header change.
        See Also:
        AccessibleTable, AccessibleTableModelChange, Constant Field Values
      • ACCESSIBLE_TABLE_COLUMN_DESCRIPTION_CHANGED

        public static final String ACCESSIBLE_TABLE_COLUMN_DESCRIPTION_CHANGED
        Constant used to indicate that the column description has changed The old value in the PropertyChangeEvent will be null and the new value will be an Integer representing the column index.
        See Also:
        AccessibleTable, Constant Field Values
      • ACCESSIBLE_ACTION_PROPERTY

        public static final String ACCESSIBLE_ACTION_PROPERTY
        Constant used to indicate that the supported set of actions has changed. The old value in the PropertyChangeEvent will be an Integer representing the old number of actions supported and the new value will be an Integer representing the new number of actions supported.
        See Also:
        AccessibleAction, Constant Field Values
      • ACCESSIBLE_HYPERTEXT_OFFSET

        public static final String ACCESSIBLE_HYPERTEXT_OFFSET
        Constant used to indicate that a hypertext element has received focus. The old value in the PropertyChangeEvent will be an Integer representing the start index in the document of the previous element that had focus and the new value will be an Integer representing the start index in the document of the current element that has focus. A value of -1 indicates that an element does not or did not have focus.
        See Also:
        AccessibleHyperlink, Constant Field Values
      • ACCESSIBLE_TEXT_PROPERTY

        public static final String ACCESSIBLE_TEXT_PROPERTY
        PropertyChangeEvent which indicates that text has changed.
        For text insertion, the oldValue is null and the newValue is an AccessibleTextSequence specifying the text that was inserted.
        For text deletion, the oldValue is an AccessibleTextSequence specifying the text that was deleted and the newValue is null.
        For text replacement, the oldValue is an AccessibleTextSequence specifying the old text and the newValue is an AccessibleTextSequence specifying the new text.
        See Also:
        getAccessibleText(), addPropertyChangeListener(java.beans.PropertyChangeListener), AccessibleTextSequence, Constant Field Values
      • ACCESSIBLE_TEXT_ATTRIBUTES_CHANGED

        public static final String ACCESSIBLE_TEXT_ATTRIBUTES_CHANGED
        PropertyChangeEvent which indicates that text attributes have changed.
        For attribute insertion, the oldValue is null and the newValue is an AccessibleAttributeSequence specifying the attributes that were inserted.
        For attribute deletion, the oldValue is an AccessibleAttributeSequence specifying the attributes that were deleted and the newValue is null.
        For attribute replacement, the oldValue is an AccessibleAttributeSequence specifying the old attributes and the newValue is an AccessibleAttributeSequence specifying the new attributes.
        Since:
        1.5
        See Also:
        getAccessibleText(), addPropertyChangeListener(java.beans.PropertyChangeListener), AccessibleAttributeSequence, Constant Field Values
    • Constructor Detail

      • AccessibleContext

        public AccessibleContext()
    • Method Detail

      • getAccessibleName

        public String getAccessibleName()
        Gets the accessibleName property of this object. The accessibleName property of an object is a localized String that designates the purpose of the object. For example, the accessibleName property of a label or button might be the text of the label or button itself. In the case of an object that doesn't display its name, the accessibleName should still be set. For example, in the case of a text field used to enter the name of a city, the accessibleName for the en_US locale could be 'city.'
        Returns:
        the localized name of the object; null if this object does not have a name
        See Also:
        setAccessibleName(java.lang.String)
      • getAccessibleDescription

        public String getAccessibleDescription()
        Gets the accessibleDescription property of this object. The accessibleDescription property of this object is a short localized phrase describing the purpose of the object. For example, in the case of a 'Cancel' button, the accessibleDescription could be 'Ignore changes and close dialog box.'
        Returns:
        the localized description of the object; null if this object does not have a description
        See Also:
        setAccessibleDescription(java.lang.String)
      • getAccessibleRole

        public abstract AccessibleRole getAccessibleRole()
        Gets the role of this object. The role of the object is the generic purpose or use of the class of this object. For example, the role of a push button is AccessibleRole.PUSH_BUTTON. The roles in AccessibleRole are provided so component developers can pick from a set of predefined roles. This enables assistive technologies to provide a consistent interface to various tweaked subclasses of components (e.g., use AccessibleRole.PUSH_BUTTON for all components that act like a push button) as well as distinguish between subclasses that behave differently (e.g., AccessibleRole.CHECK_BOX for check boxes and AccessibleRole.RADIO_BUTTON for radio buttons).

        Note that the AccessibleRole class is also extensible, so custom component developers can define their own AccessibleRole's if the set of predefined roles is inadequate.

        Returns:
        an instance of AccessibleRole describing the role of the object
        See Also:
        AccessibleRole
      • getAccessibleParent

        public Accessible getAccessibleParent()
        Gets the Accessible parent of this object.
        Returns:
        the Accessible parent of this object; null if this object does not have an Accessible parent
      • setAccessibleParent

        public void setAccessibleParent(Accessible a)
        Sets the Accessible parent of this object. This is meant to be used only in the situations where the actual component's parent should not be treated as the component's accessible parent and is a method that should only be called by the parent of the accessible child.
        Parameters:
        a - - Accessible to be set as the parent
      • getAccessibleChildrenCount

        public abstract int getAccessibleChildrenCount()
        Returns the number of accessible children of the object.
        Returns:
        the number of accessible children of the object.
      • getAccessibleChild

        public abstract Accessible getAccessibleChild(int i)
        Returns the specified Accessible child of the object. The Accessible children of an Accessible object are zero-based, so the first child of an Accessible child is at index 0, the second child is at index 1, and so on.
        Parameters:
        i - zero-based index of child
        Returns:
        the Accessible child of the object
        See Also:
        getAccessibleChildrenCount()
      • getLocale

        public abstract Locale getLocale()
                                  throws IllegalComponentStateException
        Gets the locale of the component. If the component does not have a locale, then the locale of its parent is returned.
        Returns:
        this component's locale. If this component does not have a locale, the locale of its parent is returned.
        Throws:
        IllegalComponentStateException - If the Component does not have its own locale and has not yet been added to a containment hierarchy such that the locale can be determined from the containing parent.
      • removePropertyChangeListener

        public void removePropertyChangeListener(PropertyChangeListener listener)
        Removes a PropertyChangeListener from the listener list. This removes a PropertyChangeListener that was registered for all properties.
        Parameters:
        listener - The PropertyChangeListener to be removed
      • getAccessibleAction

        public AccessibleAction getAccessibleAction()
        Gets the AccessibleAction associated with this object that supports one or more actions.
        Returns:
        AccessibleAction if supported by object; else return null
        See Also:
        AccessibleAction
      • getAccessibleComponent

        public AccessibleComponent getAccessibleComponent()
        Gets the AccessibleComponent associated with this object that has a graphical representation.
        Returns:
        AccessibleComponent if supported by object; else return null
        See Also:
        AccessibleComponent
      • getAccessibleSelection

        public AccessibleSelection getAccessibleSelection()
        Gets the AccessibleSelection associated with this object which allows its Accessible children to be selected.
        Returns:
        AccessibleSelection if supported by object; else return null
        See Also:
        AccessibleSelection
      • getAccessibleText

        public AccessibleText getAccessibleText()
        Gets the AccessibleText associated with this object presenting text on the display.
        Returns:
        AccessibleText if supported by object; else return null
        See Also:
        AccessibleText
      • getAccessibleEditableText

        public AccessibleEditableText getAccessibleEditableText()
        Gets the AccessibleEditableText associated with this object presenting editable text on the display.
        Returns:
        AccessibleEditableText if supported by object; else return null
        Since:
        1.4
        See Also:
        AccessibleEditableText
      • getAccessibleValue

        public AccessibleValue getAccessibleValue()
        Gets the AccessibleValue associated with this object that supports a Numerical value.
        Returns:
        AccessibleValue if supported by object; else return null
        See Also:
        AccessibleValue
      • getAccessibleIcon

        public AccessibleIcon[] getAccessibleIcon()
        Gets the AccessibleIcons associated with an object that has one or more associated icons
        Returns:
        an array of AccessibleIcon if supported by object; otherwise return null
        Since:
        1.3
        See Also:
        AccessibleIcon
      • getAccessibleRelationSet

        public AccessibleRelationSet getAccessibleRelationSet()
        Gets the AccessibleRelationSet associated with an object
        Returns:
        an AccessibleRelationSet if supported by object; otherwise return null
        Since:
        1.3
        See Also:
        AccessibleRelationSet
      • getAccessibleTable

        public AccessibleTable getAccessibleTable()
        Gets the AccessibleTable associated with an object
        Returns:
        an AccessibleTable if supported by object; otherwise return null
        Since:
        1.3
        See Also:
        AccessibleTable
Java™ Platform
Standard Ed. 8

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For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2022, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.

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