- All Implemented Interfaces:
Serializable
Component
hierarchy to which Component belongs.
- Hierarchy Change Events (HierarchyListener)
- addition of an ancestor
- removal of an ancestor
- hierarchy made displayable
- hierarchy made undisplayable
- hierarchy shown on the screen (both visible and displayable)
- hierarchy hidden on the screen (either invisible or undisplayable)
- Ancestor Reshape Events (HierarchyBoundsListener)
- an ancestor was resized
- an ancestor was moved
Hierarchy events are provided for notification purposes ONLY. The AWT will automatically handle changes to the hierarchy internally so that GUI layout and displayability works properly regardless of whether a program is receiving these events or not.
This event is generated by a Container object (such as a Panel) when the
Container is added, removed, moved, or resized, and passed down the
hierarchy. It is also generated by a Component object when that object's
addNotify, removeNotify, show, or
hide method is called. The ANCESTOR_MOVED and
ANCESTOR_RESIZED
events are dispatched to every HierarchyBoundsListener or
HierarchyBoundsAdapter object which registered to receive
such events using the Component's addHierarchyBoundsListener
method. (HierarchyBoundsAdapter objects implement the
HierarchyBoundsListener interface.) The HIERARCHY_CHANGED events are
dispatched to every HierarchyListener object which registered
to receive such events using the Component's addHierarchyListener
method. Each such listener object gets this HierarchyEvent
when the event occurs.
An unspecified behavior will be caused if the id parameter
of any particular HierarchyEvent instance is not
in the range from HIERARCHY_FIRST to HIERARCHY_LAST.
The changeFlags parameter of any HierarchyEvent instance takes one of the following
values:
-
HierarchyEvent.PARENT_CHANGED -
HierarchyEvent.DISPLAYABILITY_CHANGED -
HierarchyEvent.SHOWING_CHANGED
- Since:
- 1.3
- See Also:
-
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final intThe event id indicating an ancestor-Container was moved.static final intThe event id indicating an ancestor-Container was resized.static final intA change flag indicates that theHIERARCHY_CHANGEDevent was generated due to the changing of the hierarchy displayability.static final intThe event id indicating that modification was made to the entire hierarchy tree.static final intMarks the first integer id for the range of hierarchy event ids.static final intMarks the last integer id for the range of ancestor event ids.static final intA change flag indicates that theHIERARCHY_CHANGEDevent was generated by a reparenting operation.static final intA change flag indicates that theHIERARCHY_CHANGEDevent was generated due to the changing of the hierarchy showing state.Fields declared in class java.awt.AWTEvent
ACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, consumed, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, HIERARCHY_BOUNDS_EVENT_MASK, HIERARCHY_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, WINDOW_STATE_EVENT_MASKFields declared in class java.util.EventObject
source -
Constructor Summary
ConstructorsConstructorDescriptionHierarchyEvent(Component source, int id, Component changed, Container changedParent) Constructs anHierarchyEventobject to identify a change in theComponenthierarchy.HierarchyEvent(Component source, int id, Component changed, Container changedParent, long changeFlags) Constructs anHierarchyEventobject to identify a change in theComponenthierarchy. -
Method Summary
Modifier and TypeMethodDescriptionReturns the Component at the top of the hierarchy which was changed.Returns the parent of the Component returned bygetChanged().longReturns a bitmask which indicates the type(s) of HIERARCHY_CHANGED events represented in this event object.Returns the originator of the event.Returns a parameter string identifying this event.Methods declared in class java.util.EventObject
getSource
-
Field Details
-
HIERARCHY_FIRST
public static final int HIERARCHY_FIRSTMarks the first integer id for the range of hierarchy event ids.- See Also:
-
HIERARCHY_CHANGED
public static final int HIERARCHY_CHANGEDThe event id indicating that modification was made to the entire hierarchy tree.- See Also:
-
ANCESTOR_MOVED
public static final int ANCESTOR_MOVEDThe event id indicating an ancestor-Container was moved.- See Also:
-
ANCESTOR_RESIZED
public static final int ANCESTOR_RESIZEDThe event id indicating an ancestor-Container was resized.- See Also:
-
HIERARCHY_LAST
public static final int HIERARCHY_LASTMarks the last integer id for the range of ancestor event ids.- See Also:
-
PARENT_CHANGED
public static final int PARENT_CHANGEDA change flag indicates that theHIERARCHY_CHANGEDevent was generated by a reparenting operation.- See Also:
-
DISPLAYABILITY_CHANGED
public static final int DISPLAYABILITY_CHANGEDA change flag indicates that theHIERARCHY_CHANGEDevent was generated due to the changing of the hierarchy displayability. To discern the current displayability of the hierarchy, call theComponent.isDisplayablemethod. Displayability changes occur in response to explicit or implicit calls of theComponent.addNotifyandComponent.removeNotifymethods.- See Also:
-
SHOWING_CHANGED
public static final int SHOWING_CHANGEDA change flag indicates that theHIERARCHY_CHANGEDevent was generated due to the changing of the hierarchy showing state. To discern the current showing state of the hierarchy, call theComponent.isShowingmethod. Showing state changes occur when either the displayability or visibility of the hierarchy occurs. Visibility changes occur in response to explicit or implicit calls of theComponent.showandComponent.hidemethods.- See Also:
-
-
Constructor Details
-
HierarchyEvent
Constructs anHierarchyEventobject to identify a change in theComponenthierarchy.This method throws an
IllegalArgumentExceptionifsourceisnull.- Parameters:
source- TheComponentobject that originated the eventid- An integer indicating the type of event. For information on allowable values, see the class description forHierarchyEventchanged- TheComponentat the top of the hierarchy which was changedchangedParent- The parent of thechangedcomponent. This may be the parent before or after the change, depending on the type of change- Throws:
IllegalArgumentException- ifsourceisnull- See Also:
-
HierarchyEvent
public HierarchyEvent(Component source, int id, Component changed, Container changedParent, long changeFlags) Constructs anHierarchyEventobject to identify a change in theComponenthierarchy.This method throws an
IllegalArgumentExceptionifsourceisnull.- Parameters:
source- TheComponentobject that originated the eventid- An integer indicating the type of event. For information on allowable values, see the class description forHierarchyEventchanged- TheComponentat the top of the hierarchy which was changedchangedParent- The parent of thechangedcomponent. This may be the parent before or after the change, depending on the type of changechangeFlags- A bitmask which indicates the type(s) of theHIERARCHY_CHANGEDevents represented in this event object. For information on allowable values, see the class description forHierarchyEvent- Throws:
IllegalArgumentException- ifsourceis null- See Also:
-
-
Method Details
-
getComponent
Returns the originator of the event.- Returns:
- the
Componentobject that originated the event, ornullif the object is not aComponent.
-
getChanged
Returns the Component at the top of the hierarchy which was changed.- Returns:
- the changed Component
-
getChangedParent
Returns the parent of the Component returned bygetChanged(). For a HIERARCHY_CHANGED event where the change was of type PARENT_CHANGED via a call toContainer.add, the parent returned is the parent after the add operation. For a HIERARCHY_CHANGED event where the change was of type PARENT_CHANGED via a call toContainer.remove, the parent returned is the parent before the remove operation. For all other events and types, the parent returned is the parent during the operation.- Returns:
- the parent of the changed Component
-
getChangeFlags
public long getChangeFlags()Returns a bitmask which indicates the type(s) of HIERARCHY_CHANGED events represented in this event object. The bits have been bitwise-ored together.- Returns:
- the bitmask, or 0 if this is not an HIERARCHY_CHANGED event
-
paramString
Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.- Overrides:
paramStringin classAWTEvent- Returns:
- a string identifying the event and its attributes
-