org.eclipse.swt.events.KeyEvent Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2008, 2012 Innoopract Informationssysteme GmbH and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Innoopract Informationssysteme GmbH - initial API and implementation
* EclipseSource - ongoing development
******************************************************************************/
package org.eclipse.swt.events;
import org.eclipse.swt.widgets.Event;
/**
* Instances of this class are sent as a result of keys being pressed and
* released on the keyboard.
*
* When a key listener is added to a control, the control will take part in
* widget traversal. By default, all traversal keys (such as the tab key and so
* on) are delivered to the control. In order for a control to take part in
* traversal, it should listen for traversal events. Otherwise, the user can
* traverse into a control but not out. Note that native controls such as table
* and tree implement key traversal in the operating system. It is not necessary
* to add traversal listeners for these controls, unless you want to override
* the default traversal.
*
*
* IMPORTANT: All public static members of
* this class are not part of the RWT public API. They are marked
* public only so that they can be shared within the packages provided by RWT.
* They should never be accessed from application code.
*
*
* @see KeyListener
* @see TraverseListener
*
* @since 1.2
*/
public class KeyEvent extends TypedEvent {
private static final long serialVersionUID = 1L;
/**
* the character represented by the key that was typed. This is the final
* character that results after all modifiers have been applied. For example,
* when the user types Ctrl+A, the character value is 0x01. It is important
* that applications do not attempt to modify the character value based on a
* stateMask (such as SWT.CTRL) or the resulting character will not be
* correct.
*/
public char character;
/**
* the key code of the key that was typed, as defined by the key code
* constants in class SWT. When the character field of the event
* is ambiguous, this field contains the unicode value of the original
* character. For example, typing Ctrl+M or Return both result in the
* character '\r' but the keyCode field will also contain '\r' when Return was
* typed.
*
* @see org.eclipse.swt.SWT
*/
public int keyCode;
/**
* the state of the keyboard modifier keys at the time the event was
* generated, as defined by the key code constants in class SWT.
*
* @see org.eclipse.swt.SWT
*/
public int stateMask;
/**
* A flag indicating whether the operation should be allowed. Setting this
* field to false will cancel the operation.
*/
public boolean doit;
/**
* Constructs a new instance of this class based on the information in the
* given untyped event.
*
* @param event the untyped event containing the information
*/
public KeyEvent( Event event ) {
super( event );
character = event.character;
keyCode = event.keyCode;
stateMask = event.stateMask;
doit = event.doit;
}
/**
* Returns a string containing a concise, human-readable description of the
* receiver.
*
* @return a string representation of the event
*/
@Override
public String toString() {
String string = super.toString();
return string.substring( 0, string.length() - 1 ) // remove trailing '}'
+ " character='"
+ ( ( character == 0 ) ? "\\0" : "" + character )
+ "'"
+ " keyCode="
+ keyCode
+ " stateMask="
+ stateMask
+ " doit="
+ doit
+ "}";
}
}