API java : WindowEvent

java.awt.event
Class WindowEvent

java.lang.Object
  java.util.EventObject
      java.awt.AWTEvent
          java.awt.event.ComponentEvent
              java.awt.event.WindowEvent

All Implemented Interfaces:

Serializable

public class WindowEvent
extends ComponentEvent

A low-level event that indicates that a window has changed its status. This low-level event is generated by a Window object when it is opened, closed, activated, deactivated, iconified, or deiconified, or when focus is transfered into or out of the Window.

The event is passed to every WindowListener or WindowAdapter object which registered to receive such events using the window's addWindowListener method. (WindowAdapter objects implement the WindowListener interface.) Each such listener object gets this WindowEvent when the event occurs.

Since:

JDK1.1

See Also:

WindowAdapter, WindowListener, Tutorial: Writing a Window Listener, Reference: The Java Class Libraries (update file), Serialized Form

Field Summary
static int	WINDOW_ACTIVATED           The window-activated event type.
static int	WINDOW_CLOSED           The window closed event.
static int	WINDOW_CLOSING           The "window is closing" event.
static int	WINDOW_DEACTIVATED           The window-deactivated event type.
static int	WINDOW_DEICONIFIED           The window deiconified event type.
static int	WINDOW_FIRST           The first number in the range of ids used for window events.
static int	WINDOW_GAINED_FOCUS           The window-gained-focus event type.
static int	WINDOW_ICONIFIED           The window iconified event.
static int	WINDOW_LAST           The last number in the range of ids used for window events.
static int	WINDOW_LOST_FOCUS           The window-lost-focus event type.
static int	WINDOW_OPENED           The window opened event.
static int	WINDOW_STATE_CHANGED           The window-state-changed event type.

 

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, 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_MASK

 

Fields inherited from class java.util.EventObject
source

 

Constructor Summary
WindowEvent(Window source, int id)           Constructs a WindowEvent object.
WindowEvent(Window source, int id, int oldState, int newState)           Constructs a WindowEvent object with the specified previous and new window states.
WindowEvent(Window source, int id, Window opposite)           Constructs a WindowEvent object with the specified opposite Window.
WindowEvent(Window source, int id, Window opposite, int oldState, int newState)           Constructs a WindowEvent object.

 

Method Summary
int	getNewState()           For WINDOW_STATE_CHANGED events returns the new state of the window.
int	getOldState()           For WINDOW_STATE_CHANGED events returns the previous state of the window.
Window	getOppositeWindow()           Returns the other Window involved in this focus or activation change.
Window	getWindow()           Returns the originator of the event.
String	paramString()           Returns a parameter string identifying this event.

 

Methods inherited from class java.awt.event.ComponentEvent
getComponent

 

Methods inherited from class java.awt.AWTEvent
consume, getID, isConsumed, setSource, 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

WINDOW_FIRST

public static final int WINDOW_FIRST

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

See Also:

Constant Field Values

WINDOW_OPENED

public static final int WINDOW_OPENED

The window opened event. This event is delivered only the first time a window is made visible.

See Also:

Constant Field Values

WINDOW_CLOSING

public static final int WINDOW_CLOSING

The "window is closing" event. This event is delivered when the user attempts to close the window from the window's system menu. If the program does not explicitly hide or dispose the window while processing this event, the window close operation will be cancelled.

See Also:

Constant Field Values

WINDOW_CLOSED

public static final int WINDOW_CLOSED

The window closed event. This event is delivered after the window has been closed as the result of a call to dispose.

See Also:

Constant Field Values

WINDOW_ICONIFIED

public static final int WINDOW_ICONIFIED

The window iconified event. This event is delivered when the window has been changed from a normal to a minimized state. For many platforms, a minimized window is displayed as the icon specified in the window's iconImage property.

See Also:

Frame.setIconImage(java.awt.Image), Constant Field Values

WINDOW_DEICONIFIED

public static final int WINDOW_DEICONIFIED

The window deiconified event type. This event is delivered when the window has been changed from a minimized to a normal state.

See Also:

Constant Field Values

WINDOW_ACTIVATED

public static final int WINDOW_ACTIVATED

The window-activated event type. This event is delivered when the Window becomes the active Window. Only a Frame or a Dialog can be the active Window. The native windowing system may denote the active Window or its children with special decorations, such as a highlighted title bar. The active Window is always either the focused Window, or the first Frame or Dialog that is an owner of the focused Window.

See Also:

Constant Field Values

WINDOW_DEACTIVATED

public static final int WINDOW_DEACTIVATED

The window-deactivated event type. This event is delivered when the Window is no longer the active Window. Only a Frame or a Dialog can be the active Window. The native windowing system may denote the active Window or its children with special decorations, such as a highlighted title bar. The active Window is always either the focused Window, or the first Frame or Dialog that is an owner of the focused Window.

See Also:

Constant Field Values

WINDOW_GAINED_FOCUS

public static final int WINDOW_GAINED_FOCUS

The window-gained-focus event type. This event is delivered when the Window becomes the focused Window, which means that the Window, or one of its subcomponents, will receive keyboard events.

See Also:

Constant Field Values

WINDOW_LOST_FOCUS

public static final int WINDOW_LOST_FOCUS

The window-lost-focus event type. This event is delivered when a Window is no longer the focused Window, which means keyboard events will no longer be delivered to the Window or any of its subcomponents.

See Also:

Constant Field Values

WINDOW_STATE_CHANGED

public static final int WINDOW_STATE_CHANGED

The window-state-changed event type. This event is delivered when a Window's state is changed by virtue of it being iconified, maximized etc.

Since:

1.4

See Also:

Constant Field Values

WINDOW_LAST

public static final int WINDOW_LAST

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

See Also:

Constant Field Values

WindowEvent

public WindowEvent(Window source,
                   int id,
                   Window opposite,
                   int oldState,
                   int newState)

Constructs a WindowEvent object.

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

Parameters:

source - the Window object that originated the event

id - an integer indicating the type of event.

opposite - the other window involved in the focus or activation change, or null

oldState - previous state of the window for window state change event

newState - new state of the window for window state change event

Throws:

IllegalArgumentException - if source is null

Since:

1.4

WindowEvent

public WindowEvent(Window source,
                   int id,
                   Window opposite)

Constructs a WindowEvent object with the specified opposite Window. The opposite Window is the other Window involved in this focus or activation change. For a WINDOW_ACTIVATED or WINDOW_GAINED_FOCUS event, this is the Window that lost activation or focus. For a WINDOW_DEACTIVATED or WINDOW_LOST_FOCUS event, this is the Window that gained activation or focus. If this focus change occurs with a native application, with a Java application in a different VM, or with no other Window, then the opposite Window is null.

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

Parameters:

source - the Window object that originated the event

id - WINDOW_ACTIVATED, WINDOW_DEACTIVATED, WINDOW_GAINED_FOCUS, or WINDOW_LOST_FOCUS. It is expected that this constructor will not be used for other WindowEvent types because the opposite Window of such events will always be null

opposite - the other Window involved in the focus or activation change, or null

Throws:

IllegalArgumentException - if source is null

WindowEvent

public WindowEvent(Window source,
                   int id,
                   int oldState,
                   int newState)

Constructs a WindowEvent object with the specified previous and new window states.

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

Parameters:

source - the Window object that originated the event

id - WINDOW_STATE_CHANGED event type. It is expected that this constructor will not be used for other WindowEvent types, because the previous and new window states are meaningless for other event types.

oldState - an integer representing the previous window state

newState - an integer representing the new window state

Throws:

IllegalArgumentException - if source is null

Since:

1.4

WindowEvent

public WindowEvent(Window source,
                   int id)

Constructs a WindowEvent object.

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

Parameters:

source - the Window object that originated the event

id - an integer indicating the type of event

Throws:

IllegalArgumentException - if source is null

getWindow

public Window getWindow()

Returns the originator of the event.

Returns:

the Window object that originated the event

getOppositeWindow

public Window getOppositeWindow()

Returns the other Window involved in this focus or activation change. For a WINDOW_ACTIVATED or WINDOW_GAINED_FOCUS event, this is the Window that lost activation or focus. For a WINDOW_DEACTIVATED or WINDOW_LOST_FOCUS event, this is the Window that gained activation or focus. For any other type of WindowEvent, or if the focus or activation change occurs with a native application, with a Java application in a different VM or context, or with no other Window, null is returned.

Returns:

the other Window involved in the focus or activation change, or null

Since:

1.4

getOldState

public int getOldState()

For WINDOW_STATE_CHANGED events returns the previous state of the window. The state is represented as a bitwise mask.

• NORMAL
  Indicates that no state bits are set.
• ICONIFIED
• MAXIMIZED_HORIZ
• MAXIMIZED_VERT
• MAXIMIZED_BOTH
  Concatenates MAXIMIZED_HORIZ and MAXIMIZED_VERT.

Returns:

a bitwise mask of the previous window state

Since:

1.4

See Also:

Frame.getExtendedState()

getNewState

public int getNewState()

For WINDOW_STATE_CHANGED events returns the new state of the window. The state is represented as a bitwise mask.

• NORMAL
  Indicates that no state bits are set.
• ICONIFIED
• MAXIMIZED_HORIZ
• MAXIMIZED_VERT
• MAXIMIZED_BOTH
  Concatenates MAXIMIZED_HORIZ and MAXIMIZED_VERT.

Returns:

a bitwise mask of the new window state

Since:

1.4

See Also:

Frame.getExtendedState()

paramString

public String paramString()

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

Overrides:

paramString in class ComponentEvent

Returns:

a string identifying the event and its attributes