org.havi.ui.event

Class HItemEvent

java.lang.Object

java.util.EventObject

java.awt.AWTEvent

org.havi.ui.event.HItemEvent

All Implemented Interfaces:

Serializable

public class HItemEvent
extends AWTEvent

An HItemEvent event is used to interact with a component implementing the HSelectionInputPreferred interface as follows:

• An HItemEvent event may be sent from the HAVi system to the component to change the state of the component, and the selection set held by the component.
• An HItemEvent event is sent from the component to all registered HItemListeners when a change to the component state or selection set occurs.

The HItemEvent event class therefore provides support for selecting and clearing individual elements, selecting or clearing all elements and managing the currently focused element, i.e. the item whose selection state is toggled by some user interaction.

All interoperable HAVi components which expect to receive HItemEvent events should implement the HSelectionInputPreferred interface.

See Also:

HListGroup, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	ITEM_CLEARED An item event with this id is sent from the component whenever an item is removed from the selection set of an HItemValue component.
static int	ITEM_END_CHANGE An item event with this id indicates that the selection of an HItemValue component has been finally set.
static int	ITEM_FIRST The first integer id in the range of event ids supported by the HItemEvent class.
static int	ITEM_LAST The last integer id in the range of event ids supported by the HItemEvent class.
static int	ITEM_SELECTED An item event with this id is sent from the component whenever an item is added to the selection set of an HItemValue component.
static int	ITEM_SELECTION_CLEARED An item event with this id is sent to or from the component whenever the entire selection set of an HItemValue component is removed.
static int	ITEM_SET_CURRENT An item event with this id is sent to or from the component whenever the current item of an HItemValue component changes.
static int	ITEM_SET_NEXT An item event with this id is sent to or from the component whenever the current item of an HItemValue component changes to the next item in the group.
static int	ITEM_SET_PREVIOUS An item event with this id is sent to or from the component whenever the current item of an HItemValue component changes to the previous item in the group.
static int	ITEM_START_CHANGE An item event with this id indicates that the selection of an HItemValue component may be about to change.
static int	ITEM_TOGGLE_SELECTED An item event with this id may be sent to an HItemValue component to toggle the selection state of the currently focused item.
static int	SCROLL_LESS An HItemEvent with this id is sent to the widget to request a decrease of the scrolling position of an HItemValue by one unit in response to mouse actions.
static int	SCROLL_MORE An HItemEvent with this id is sent to the widget to request an increase of the scrolling position of an HItemValue by one unit in response to mouse actions.
static int	SCROLL_PAGE_LESS An HItemEvent with this id is sent to the widget to request a decrease of the scrolling position of an HItemValue by one block in response to mouse actions.
static int	SCROLL_PAGE_MORE An HItemEvent with this id is sent to the widget to request an increase of the scrolling position of an HItemValue by one block in response to mouse actions.

Fields inherited from class java.awt.AWTEvent

ACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, consumed, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, id, INPUT_METHOD_EVENT_MASK, INVOCATION_EVENT_MASK, ITEM_EVENT_MASK, KEY_EVENT_MASK, MOUSE_EVENT_MASK, MOUSE_MOTION_EVENT_MASK, MOUSE_WHEEL_EVENT_MASK, PAINT_EVENT_MASK, RESERVED_ID_MAX, TEXT_EVENT_MASK, WINDOW_EVENT_MASK, WINDOW_FOCUS_EVENT_MASK

Fields inherited from class java.util.EventObject

source

Constructor Summary

Constructors

Constructor and Description
HItemEvent(HSelectionInputPreferred source, int id, Object item) Constructs an HItemEvent

Method Summary

Methods

Modifier and Type	Method and Description
Object	getItem() Retrieve the item which caused this HItemEvent.

Methods inherited from class java.awt.AWTEvent

consume, getID, isConsumed, paramString, toString

Methods inherited from class java.util.EventObject

getSource

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

ITEM_FIRST

public static final int ITEM_FIRST

The first integer id in the range of event ids supported by the HItemEvent class.

See Also:

Constant Field Values

ITEM_START_CHANGE

public static final int ITEM_START_CHANGE

An item event with this id indicates that the selection of an HItemValue component may be about to change. This event is sent to or from the component when the user causes the component to enter selection mode. Note that it is a platform specific implementation option for such components to enter selection mode automatically e.g. when they receive input focus. In such a case the order in which the HFocusEvent and HItemEvent are sent is platform specific.

See Also:

HSelectionInputPreferred.getSelectionMode(), Constant Field Values

ITEM_TOGGLE_SELECTED

public static final int ITEM_TOGGLE_SELECTED

An item event with this id may be sent to an HItemValue component to toggle the selection state of the currently focused item. Note that events of this type are never sent to listeners from the component; instead an event of type ITEM_SELECTED or ITEM_CLEARED is sent in response to an event with this id, depending on the new state of the currently focused item.

See Also:

Constant Field Values

ITEM_SELECTED

public static final int ITEM_SELECTED

An item event with this id is sent from the component whenever an item is added to the selection set of an HItemValue component. Note that events of this type are silently ignored if they are sent to the component.

See Also:

Constant Field Values

ITEM_CLEARED

public static final int ITEM_CLEARED

An item event with this id is sent from the component whenever an item is removed from the selection set of an HItemValue component. Note that events of this type are silently ignored if they are sent to the component.

See Also:

Constant Field Values

ITEM_SELECTION_CLEARED

public static final int ITEM_SELECTION_CLEARED

An item event with this id is sent to or from the component whenever the entire selection set of an HItemValue component is removed.

See Also:

Constant Field Values

ITEM_SET_CURRENT

public static final int ITEM_SET_CURRENT

An item event with this id is sent to or from the component whenever the current item of an HItemValue component changes.

See Also:

Constant Field Values

ITEM_SET_PREVIOUS

public static final int ITEM_SET_PREVIOUS

An item event with this id is sent to or from the component whenever the current item of an HItemValue component changes to the previous item in the group.

See Also:

Constant Field Values

ITEM_SET_NEXT

public static final int ITEM_SET_NEXT

An item event with this id is sent to or from the component whenever the current item of an HItemValue component changes to the next item in the group.

See Also:

Constant Field Values

SCROLL_MORE

public static final int SCROLL_MORE

An HItemEvent with this id is sent to the widget to request an increase of the scrolling position of an HItemValue by one unit in response to mouse actions. Use of this constant is implementation-specific.

See Also:

Constant Field Values

SCROLL_LESS

public static final int SCROLL_LESS

An HItemEvent with this id is sent to the widget to request a decrease of the scrolling position of an HItemValue by one unit in response to mouse actions. Use of this constant is implementation-specific.

See Also:

Constant Field Values

SCROLL_PAGE_MORE

public static final int SCROLL_PAGE_MORE

An HItemEvent with this id is sent to the widget to request an increase of the scrolling position of an HItemValue by one block in response to mouse actions. The value of a block is implementation-dependent. Use of this constant is implementation-specific.

See Also:

Constant Field Values

SCROLL_PAGE_LESS

public static final int SCROLL_PAGE_LESS

An HItemEvent with this id is sent to the widget to request a decrease of the scrolling position of an HItemValue by one block in response to mouse actions. The value of a block is implementation-dependent. Use of this constant is implementation-specific.

See Also:

Constant Field Values

ITEM_END_CHANGE

public static final int ITEM_END_CHANGE

An item event with this id indicates that the selection of an HItemValue component has been finally set. This event is sent to or from the component when the user causes the component to leave selection mode. Note that it is a platform specific implementation option for such components to leave selection mode automatically e.g. when they lose input focus. In such a case the order in which the HFocusEvent and HItemEvent are sent is platform specific.

See Also:

HSelectionInputPreferred.getSelectionMode(), Constant Field Values

ITEM_LAST

public static final int ITEM_LAST

The last integer id in the range of event ids supported by the HItemEvent class.

See Also:

Constant Field Values

Constructor Detail

HItemEvent

public HItemEvent(HSelectionInputPreferred source,
          int id,
          Object item)

Constructs an HItemEvent

Parameters:

source - The HSelectionInputPreferred component whose value or current item has been modified.

id - The event id of the HItemEvent generated by the HSelectionInputPreferred component. This is the value that will be returned by the event object's getID method.

item - The item which caused the change, or null if this information is not available. If the event is sent to listeners, this information shall be provided if the event id is one of ITEM_SELECTED, ITEM_CLEARED, ITEM_SET_NEXT or ITEM_SET_PREVIOUS.

Method Detail

getItem

public Object getItem()

Retrieve the item which caused this HItemEvent. This information is not available for the ITEM_SELECTION_CLEARED event id.

Returns:

the item which was selected or cleared, or became the current item, or null if this information is not available for this event.