javafx.scene.input

Class KeyEvent

java.lang.Object

java.util.EventObject

javafx.event.Event

javafx.scene.input.InputEvent

javafx.scene.input.KeyEvent

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class KeyEvent
extends InputEvent

An event which indicates that a keystroke occurred in a Node.

This event is generated when a key is pressed, released, or typed. Depending on the type of the event it is passed to onKeyPressed, onKeyTyped or onKeyReleased function.

"Key typed" events are higher-level and generally do not depend on the platform or keyboard layout. They are generated when a Unicode character is entered, and are the preferred way to find out about character input. In the simplest case, a key typed event is produced by a single key press (e.g., 'a'). Often, however, characters are produced by series of key presses (e.g., SHIFT + 'a'), and the mapping from key pressed events to key typed events may be many-to-one or many-to-many. Key releases are not usually necessary to generate a key typed event, but there are some cases where the key typed event is not generated until a key is released (e.g., entering ASCII sequences via the Alt-Numpad method in Windows). No key typed events are generated for keys that don't generate Unicode characters (e.g., action keys, modifier keys, etc.).

The char variable always contains a valid Unicode character or CHAR_UNDEFINED. Character input is reported by key typed events; key pressed and key released events are not necessarily associated with character input. Therefore, the char variable is guaranteed to be meaningful only for key typed events.

For key pressed and key released events, the code variable contains the event's key code. For key typed events, the code variable always contains KeyCode.UNDEFINED.

"Key pressed" and "key released" events are lower-level and depend on the platform and keyboard layout. They are generated whenever a key is pressed or released, and are the only way to find out about keys that don't generate character input (e.g., action keys, modifier keys, etc.). The key being pressed or released is indicated by the code variable, which contains a virtual key code.

For triggering context menus see the ContextMenuEvent.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static EventType<KeyEvent>	ANY Common supertype for all key event types.
static java.lang.String	CHAR_UNDEFINED KEY_PRESSED and KEY_RELEASED events which do not map to a valid Unicode character use this for the keyChar value.
static EventType<KeyEvent>	KEY_PRESSED This event occurs when a key has been pressed.
static EventType<KeyEvent>	KEY_RELEASED This event occurs when a key has been released.
static EventType<KeyEvent>	KEY_TYPED This event occurs when a key has been typed (pressed and released).

Fields inherited from class javafx.event.Event

consumed, eventType, NULL_SOURCE_TARGET, target

Fields inherited from class java.util.EventObject

source

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.String	getCharacter() The unicode character associated with the key typed event.
KeyCode	getCode() The key code associated with the key in this key pressed or key released event.
java.lang.String	getText() A String describing the key code, such as "HOME", "F1" or "A", for key pressed and key released events.
boolean	isAltDown() Returns whether or not the Alt modifier is down on this event.
boolean	isControlDown() Returns whether or not the Control modifier is down on this event.
boolean	isMetaDown() Returns whether or not the Meta modifier is down on this event.
boolean	isShiftDown() Returns whether or not the Shift modifier is down on this event.
boolean	isShortcutDown() Returns whether or not the host platform common shortcut modifier is down on this event.
java.lang.String	toString() Returns a string representation of this KeyEvent object.

Methods inherited from class javafx.event.Event

clone, consume, copyFor, fireEvent, getEventType, getTarget, isConsumed

Methods inherited from class java.util.EventObject

getSource

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

ANY

public static final EventType<KeyEvent> ANY

Common supertype for all key event types.

KEY_PRESSED

public static final EventType<KeyEvent> KEY_PRESSED

This event occurs when a key has been pressed.

KEY_RELEASED

public static final EventType<KeyEvent> KEY_RELEASED

This event occurs when a key has been released.

KEY_TYPED

public static final EventType<KeyEvent> KEY_TYPED

This event occurs when a key has been typed (pressed and released). This event contains the character field containing the typed string, the code and text fields are not used.

CHAR_UNDEFINED

public static final java.lang.String CHAR_UNDEFINED

KEY_PRESSED and KEY_RELEASED events which do not map to a valid Unicode character use this for the keyChar value.

Method Detail

getCharacter

public final java.lang.String getCharacter()

The unicode character associated with the key typed event. For example, char will have the value "A" for a key typed event generated by pressing SHIFT + 'a'. For key pressed and key released events, char is always CHAR_UNDEFINED.

Returns:

The unicode character associated with the key typed event

getText

public final java.lang.String getText()

A String describing the key code, such as "HOME", "F1" or "A", for key pressed and key released events. For key typed events, text is always the empty string.

Returns:

A String describing the key code

getCode

public final KeyCode getCode()

The key code associated with the key in this key pressed or key released event. For key typed events, code is always KeyCode.UNDEFINED.

Returns:

The key code associated with the key in this event, KeyCode.UNDEFINED for key typed event

isShiftDown

public final boolean isShiftDown()

Returns whether or not the Shift modifier is down on this event.

Returns:

whether or not the Shift modifier is down on this event.

isControlDown

public final boolean isControlDown()

Returns whether or not the Control modifier is down on this event.

Returns:

whether or not the Control modifier is down on this event.

isAltDown

public final boolean isAltDown()

Returns whether or not the Alt modifier is down on this event.

Returns:

whether or not the Alt modifier is down on this event.

isMetaDown

public final boolean isMetaDown()

Returns whether or not the Meta modifier is down on this event.

Returns:

whether or not the Meta modifier is down on this event.

isShortcutDown

public final boolean isShortcutDown()

Returns whether or not the host platform common shortcut modifier is down on this event. This common shortcut modifier is a modifier key which is used commonly in shortcuts on the host platform. It is for example control on Windows and meta (command key) on Mac.

Returns:

true if the shortcut modifier is down, false otherwise

toString

public java.lang.String toString()

Returns a string representation of this KeyEvent object.

Overrides:

toString in class java.util.EventObject

Returns:

a string representation of this KeyEvent object.