java.lang.Object | ||||
↳ | java.util.EventObject | |||
↳ | java.awt.AWTEvent | |||
↳ | java.awt.event.ComponentEvent | |||
↳ | java.awt.event.ContainerEvent |
A low-level event which indicates that a container's contents changed because a component was added or removed.
Container events are provided for notification purposes ONLY; The AWT will automatically handle changes to the containers contents internally so that the program works properly regardless of whether the program is receiving these events or not.
This low-level event is generated by a container object (such as a
Panel) when a component is added to it or removed from it.
The event is passed to every ContainerListener
or ContainerAdapter
object which registered to receive such
events using the component's addContainerListener
method.
(ContainerAdapter
objects implement the
ContainerListener
interface.) Each such listener object
gets this ContainerEvent
when the event occurs.
Constants | |||||||||||
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int | COMPONENT_ADDED | This event indicates that a component was added to the container. | |||||||||
int | COMPONENT_REMOVED | This event indicates that a component was removed from the container. | |||||||||
int | CONTAINER_FIRST | The first number in the range of ids used for container events. | |||||||||
int | CONTAINER_LAST | The last number in the range of ids used for container events. |
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Inherited Constants | |||||||||||
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From class
java.awt.event.ComponentEvent
| |||||||||||
From class
java.awt.AWTEvent
|
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Inherited Fields | |||||||||||
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From class
java.awt.AWTEvent
| |||||||||||
From class
java.util.EventObject
|
Public Constructors | |||||||||||
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Constructs a
ContainerEvent object. |
Public Methods | |||||||||||
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Returns the component that was affected by the event.
| |||||||||||
Returns the originator of the event.
| |||||||||||
Returns a parameter string identifying this event.
|
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Inherited Methods | |||||||||||
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From class
java.awt.event.ComponentEvent
| |||||||||||
From class
java.awt.AWTEvent
| |||||||||||
From class
java.util.EventObject
| |||||||||||
From class
java.lang.Object
|
This event indicates that a component was added to the container.
This event indicates that a component was removed from the container.
The first number in the range of ids used for container events.
The last number in the range of ids used for container events.
Constructs a ContainerEvent
object.
Note that passing in an invalid id
results in
unspecified behavior. This method throws an
IllegalArgumentException
if source
is null
.
source | the Component object (container)
that originated the event |
---|---|
id | an integer indicating the type of event |
child | the component that was added or removed |
IllegalArgumentException | if source is null
|
---|
Returns the component that was affected by the event.
Returns the originator of the event.
Container
object that originated
the event, or null
if the object is not a
Container
.
Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.