Mercurial > projects > dwt2
view org.eclipse.swt.gtk.linux.x86/src/org/eclipse/swt/widgets/Listener.d @ 104:88652073d1c2
More work on icu
author | Frank Benoit <benoit@tionex.de> |
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date | Sat, 02 May 2009 11:27:24 +0200 |
parents | 7a2dd761a8b2 |
children |
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/******************************************************************************* * Copyright (c) 2000, 2005 IBM Corporation 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: * IBM Corporation - initial API and implementation * Port to the D programming language: * Frank Benoit <benoit@tionex.de> *******************************************************************************/ module org.eclipse.swt.widgets.Listener; import java.lang.all; import org.eclipse.swt.widgets.Event; version(Tango){ import tango.core.Traits; import tango.core.Tuple; } else { // Phobos import std.traits; import std.typetuple; } /** * Implementers of <code>Listener</code> provide a simple * <code>handleEvent()</code> method that is used internally * by SWT to dispatch events. * <p> * After creating an instance of a class that implements this interface * it can be added to a widget using the * <code>addListener(int eventType, Listener handler)</code> method and * removed using the * <code>removeListener (int eventType, Listener handler)</code> method. * When the specified event occurs, <code>handleEvent(...)</code> will * be sent to the instance. * </p> * <p> * Classes which implement this interface are described within SWT as * providing the <em>untyped listener</em> API. Typically, widgets will * also provide a higher-level <em>typed listener</em> API, that is based * on the standard <code>java.util.EventListener</code> pattern. * </p> * <p> * Note that, since all internal SWT event dispatching is based on untyped * listeners, it is simple to build subsets of SWT for use on memory * constrained, small footprint devices, by removing the classes and * methods which implement the typed listener API. * </p> * * @see Widget#addListener * @see java.util.EventListener * @see org.eclipse.swt.events */ public interface Listener { /** * Sent when an event that the receiver has registered for occurs. * * @param event the event which occurred */ void handleEvent (Event event); } /// Helper class for the dgListener template function private class _DgListenerT(Dg,T...) : Listener { version(Tango){ alias ParameterTupleOf!(Dg) DgArgs; static assert( is(DgArgs == Tuple!(Event,T)), "Delegate args not correct: delegate args: ("~ DgArgs.stringof~ ") vs. passed args: ("~ Tuple!(Event,T).stringof~")" ); } else { // Phobos alias ParameterTypeTuple!(Dg) DgArgs; static assert( is(DgArgs == TypeTuple!(Event,T)), "Delegate args not correct: delegate args: ("~ DgArgs.stringof~ ") vs. passed args: ("~ TypeTuple!(Event,T).stringof~")" ); } Dg dg; T t; private this( Dg dg, T t ){ this.dg = dg; static if( T.length > 0 ){ this.t = t; } } void handleEvent( Event e ){ dg(e,t); } } /++ + dgListener creates a class implementing the Listener interface and delegating the call to + handleEvent to the users delegate. This template function will store also additional parameters. + + Examle of usage: + --- + void handleTextEvent (Event e, int inset ) { + // ... + } + text.addListener (SWT.FocusOut, dgListener( &handleTextEvent, inset )); + --- +/ Listener dgListener( Dg, T... )( Dg dg, T args ){ return new _DgListenerT!( Dg, T )( dg, args ); }