java.awt.event

Class ContainerEvent

Implemented Interfaces:
Serializable

public class ContainerEvent
extends ComponentEvent

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.

Since:
1.1
See Also:
ContainerAdapter, ContainerListener, Tutorial: Writing a Container Listener, Reference: The Java Class Libraries (update file), Serialized Form

Field Summary

static int
COMPONENT_ADDED
This event indicates that a component was added to the container.
static int
COMPONENT_REMOVED
This event indicates that a component was removed from the container.
static int
CONTAINER_FIRST
The first number in the range of ids used for container events.
static int
CONTAINER_LAST
The last number in the range of ids used for container events.

Fields inherited from class java.awt.event.ComponentEvent

COMPONENT_FIRST, COMPONENT_HIDDEN, COMPONENT_LAST, COMPONENT_MOVED, COMPONENT_RESIZED, COMPONENT_SHOWN

Fields inherited from class java.awt.AWTEvent

ACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, HIERARCHY_BOUNDS_EVENT_MASK, HIERARCHY_EVENT_MASK, 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_MASK, consumed, id

Fields inherited from class java.util.EventObject

source

Constructor Summary

ContainerEvent(Component source, int id, Component child)
Constructs a ContainerEvent object.

Method Summary

Component
getChild()
Returns the component that was affected by the event.
Container
getContainer()
Returns the originator of the event.
String
paramString()
Returns a parameter string identifying this event.

Methods inherited from class java.awt.event.ComponentEvent

getComponent, paramString

Methods inherited from class java.awt.AWTEvent

consume, getID, isConsumed, paramString, setSource, toString

Methods inherited from class java.util.EventObject

getSource, toString

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

COMPONENT_ADDED

public static final int COMPONENT_ADDED
This event indicates that a component was added to the container.
Field Value:
300
Usages and Demos :

View More Examples of ContainerEvent.COMPONENT_ADDED
   1:       {
   2:         case ContainerEvent.COMPONENT_ADDED:
   3:         {
   4:           ContainerEvent ce = (ContainerEvent)event;
   5:           ce.getChild ().invalidate ();

View Full Code Here
   1:         ContainerEvent ce = new ContainerEvent(this,
   2:                                                ContainerEvent.COMPONENT_ADDED,
   3:                                                comp);
   4:         ...
   5:       {
   6:       case ContainerEvent.COMPONENT_ADDED:
   7:         containerListener.componentAdded(e);
   8:         break;

View Full Code Here

COMPONENT_REMOVED

public static final int COMPONENT_REMOVED
This event indicates that a component was removed from the container.
Field Value:
301
Usages and Demos :

View More Examples of ContainerEvent.COMPONENT_REMOVED
   1:         ContainerEvent ce = new ContainerEvent(this,
   2:                                                ContainerEvent.COMPONENT_REMOVED,
   3:                                                r);
   4:         ...
   5: 
   6:       case ContainerEvent.COMPONENT_REMOVED:
   7:         containerListener.componentRemoved(e);
   8:         break;
   9:       }

View Full Code Here

CONTAINER_FIRST

public static final int CONTAINER_FIRST
The first number in the range of ids used for container events.
Field Value:
300

CONTAINER_LAST

public static final int CONTAINER_LAST
The last number in the range of ids used for container events.
Field Value:
301

Constructor Details

ContainerEvent

public ContainerEvent(Component source,
                      int id,
                      Component child)
Constructs a ContainerEvent object.

Note that passing in an invalid id results in unspecified behavior. This method throws an IllegalArgumentException if source is null.

Parameters:
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
Throws:
IllegalArgumentException - if source is null
Usages and Demos :

View More Examples of ContainerEvent(Component source,int id,Component child)
   1:             for (int i = 0; i < container.getComponentCount(); i++) {
   2:                 componentAdded(new ContainerEvent(container, i, container.getComponent(i)));
   3:             }
   4:         ...
   5:             for (int i = 0; i < container.getComponentCount(); i++) {
   6:                 componentRemoved(new ContainerEvent(container, i, container.getComponent(i)));
   7:             }
   8:         }

View Full Code Here

Method Details

getChild

public Component getChild()
Returns the component that was affected by the event.
Returns:
the Component object that was added or removed
Usages and Demos :

View More Examples of getChild()
   1: import java.awt.Graphics;
   2: import java.awt.event.ContainerEvent;
   3: import java.awt.event.ContainerListener;
   4:         ...
   5:     ContainerListener containerListener= new ContainerListener() {
   6:         public void componentAdded(ContainerEvent e) {
   7:         ...
   8:             installBorder(e.getChild());
   9:         }
  10:         ...
  11:         
  12:         public void componentRemoved(ContainerEvent e) {

View Full Code Here
   1: import jp.ujihara.java.awt.Window;
   2: import jp.ujihara.java.awt.event.ContainerEvent;
   3: import jp.ujihara.java.awt.event.ContainerListener;
   4:         ...
   5:   {
   6:     public void componentAdded(ContainerEvent e)
   7:     {
   8:         ...
   9:       if (e.getChild() instanceof JButton)
  10:         {
  11:         ...
  12:       JButton b = (JButton) e.getChild();

View Full Code Here

getContainer

public Container getContainer()
Returns the originator of the event.
Returns:
the Container object that originated the event, or null if the object is not a Container.

paramString

public String paramString()
Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.
Overrides:
paramString in interface ComponentEvent
Returns:
a string identifying the event and its attributes