Mercurial > projects > dwt-linux
view dwt/widgets/EventTable.d @ 315:21959e16bc1e
Improved Listeners access functions.
author | Frank Benoit <benoit@tionex.de> |
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date | Tue, 16 Sep 2008 15:28:21 +0200 |
parents | c0d810de7093 |
children |
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/******************************************************************************* * Copyright (c) 2000, 2008 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 dwt.widgets.EventTable; import dwt.widgets.Listener; import dwt.widgets.Event; import dwt.widgets.Listener; import dwt.widgets.TypedListener; import dwt.internal.DWTEventListener; import dwt.dwthelper.System; import dwt.DWT; import dwt.internal.DWTEventListener; /** * Instances of this class implement a simple * look up mechanism that maps an event type * to a listener. Multiple listeners for the * same event type are supported. */ class EventTable { int [] types; Listener [] listeners; int level; static final int GROW_SIZE = 4; public Listener [] getListeners (int eventType) { if (types is null) return new Listener [0]; int count = 0; for (int i=0; i<types.length; i++) { if (types [i] is eventType) count++; } if (count is 0) return new Listener [0]; Listener [] result = new Listener [count]; count = 0; for (int i=0; i<types.length; i++) { if (types [i] is eventType) { result [count++] = listeners [i]; } } return result; } public void hook (int eventType, Listener listener) { if (types is null) types = new int [GROW_SIZE]; if (listeners is null) listeners = new Listener [GROW_SIZE]; int length = types.length, index = length - 1; while (index >= 0) { if (types [index] !is 0) break; --index; } index++; if (index is length) { int [] newTypes = new int [length + GROW_SIZE]; System.arraycopy (types, 0, newTypes, 0, length); types = newTypes; Listener [] newListeners = new Listener [length + GROW_SIZE]; SimpleType!(Listener).arraycopy (listeners, 0, newListeners, 0, length); listeners = newListeners; } types [index] = eventType; listeners [index] = listener; } public bool hooks (int eventType) { if (types is null) return false; for (int i=0; i<types.length; i++) { if (types [i] is eventType) return true; } return false; } public void sendEvent (Event event) { if (types is null) return; level += level >= 0 ? 1 : -1; try { for (int i=0; i<types.length; i++) { if (event.type is DWT.None) return; if (types [i] is event.type) { Listener listener = listeners [i]; if (listener !is null) listener.handleEvent (event); } } } finally { bool compact = level < 0; level -= level >= 0 ? 1 : -1; if (compact && level is 0) { int index = 0; for (int i=0; i<types.length; i++) { if (types [i] !is 0) { types [index] = types [i]; listeners [index] = listeners [i]; index++; } } for (int i=index; i<types.length; i++) { types [i] = 0; listeners [i] = null; } } } } public int size () { if (types is null) return 0; int count = 0; for (int i=0; i<types.length; i++) { if (types [i] !is 0) count++; } return count; } void remove (int index) { if (level is 0) { int end = types.length - 1; System.arraycopy (types, index + 1, types, index, end - index); SimpleType!(Listener).arraycopy (listeners, index + 1, listeners, index, end - index); index = end; } else { if (level > 0) level = -level; } types [index] = 0; listeners [index] = null; } public void unhook (int eventType, Listener listener) { if (types is null) return; for (int i=0; i<types.length; i++) { if (types [i] is eventType && listeners [i] is listener) { remove (i); return; } } } public void unhook (int eventType, DWTEventListener listener) { if (types is null) return; for (int i=0; i<types.length; i++) { if (types [i] is eventType) { if ( auto typedListener = cast(TypedListener) listeners [i] ) { if (typedListener.getEventListener () is listener) { remove (i); return; } } } } } }