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Class java.awt.event.ComponentEvent

java.lang.Object
    |
    +----java.util.EventObject
            |
            +----java.awt.AWTEvent
                    |
                    +----java.awt.event.ComponentEvent

public class ComponentEvent

extends AWTEvent

Component events are provided for notification purposes ONLY; The AWT will automatically handle component moves and resizes internally so that GUI layout works properly regardless of whether a program is receiving these events or not.

In addition to serving as the base class for other component-related events (InputEvent, FocusEvent, WindowEvent, ContainerEvent), this class defines the events that indicate changes in a component's size, position, or visibility.

This low-level event is generated by a component object (such as a List) when the component is moved, resized, rendered invisible, or made visible again. The event is passed to every ComponentListener or ComponentAdapter object which registered to receive such events using the component's addComponentListener method. (ComponentAdapter objects implement the ComponentListener interface.) Each such listener object gets this ComponentEvent when the event occurs.

See Also:

ComponentAdapter, ComponentListener, Tutorial: Writing a Component Listener, Reference: The Java Class Libraries (update file)

COMPONENT_FIRST

The first number in the range of ids used for component events.

COMPONENT_HIDDEN

This event indicates that the component was rendered invisible.

COMPONENT_LAST

The last number in the range of ids used for component events.

COMPONENT_MOVED

This event indicates that the component's position changed.

COMPONENT_RESIZED

This event indicates that the component's size changed.

COMPONENT_SHOWN

This event indicates that the component was made visible.

ComponentEvent(Component, int)

Constructs a ComponentEvent object.

getComponent()

Returns the originator of the event.

paramString()

Returns a parameter string identifying this event.

public static final int COMPONENT_FIRST

The first number in the range of ids used for component events.

public static final int COMPONENT_LAST

The last number in the range of ids used for component events.

public static final int COMPONENT_MOVED

This event indicates that the component's position changed.

public static final int COMPONENT_RESIZED

This event indicates that the component's size changed.

public static final int COMPONENT_SHOWN

This event indicates that the component was made visible.

public static final int COMPONENT_HIDDEN

This event indicates that the component was rendered invisible.

public ComponentEvent(Component source,
                      int id)

Constructs a ComponentEvent object.

Parameters:

source - the Component object that originated the event

id - an integer indicating the type of event

public Component getComponent()

Returns the originator of the event.

Returns:

the Component object that originated the event

public String paramString()

Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.

Returns:

a string identifying the event and its attributes

Overrides:

paramString in class AWTEvent

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