001/* 002 * This library is part of OpenCms - 003 * the Open Source Content Management System 004 * 005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com) 006 * 007 * This library is free software; you can redistribute it and/or 008 * modify it under the terms of the GNU Lesser General Public 009 * License as published by the Free Software Foundation; either 010 * version 2.1 of the License, or (at your option) any later version. 011 * 012 * This library is distributed in the hope that it will be useful, 013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 015 * Lesser General Public License for more details. 016 * 017 * For further information about Alkacon Software, please see the 018 * company website: http://www.alkacon.com 019 * 020 * For further information about OpenCms, please see the 021 * project website: http://www.opencms.org 022 * 023 * You should have received a copy of the GNU Lesser General Public 024 * License along with this library; if not, write to the Free Software 025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 026 */ 027 028package org.opencms.gwt.client.ui.input; 029 030import com.google.common.base.Objects; 031import com.google.gwt.event.logical.shared.ValueChangeEvent; 032import com.google.gwt.event.logical.shared.ValueChangeHandler; 033import com.google.gwt.event.shared.EventBus; 034import com.google.gwt.event.shared.GwtEvent; 035import com.google.gwt.event.shared.HandlerRegistration; 036import com.google.gwt.event.shared.SimpleEventBus; 037 038/** 039 * The default string model implementation.<p> 040 * 041 * @since 8.0.0 042 */ 043public class CmsDefaultStringModel implements I_CmsStringModel { 044 045 /** The event bus for this class. */ 046 EventBus m_eventBus = new SimpleEventBus(); 047 048 /** 049 * A flag which indicates that the model is currently being updated, which is used to prevent infinite recursion.<p> 050 */ 051 private boolean m_active; 052 053 /** The id. */ 054 private String m_id; 055 056 /** The model value. */ 057 private String m_value; 058 059 /** 060 * Creates a new string model.<p> 061 * 062 * @param id the model id 063 */ 064 public CmsDefaultStringModel(String id) { 065 066 m_id = id; 067 m_value = ""; 068 } 069 070 /** 071 * @see com.google.gwt.event.logical.shared.HasValueChangeHandlers#addValueChangeHandler(com.google.gwt.event.logical.shared.ValueChangeHandler) 072 */ 073 public HandlerRegistration addValueChangeHandler(ValueChangeHandler<String> handler) { 074 075 return m_eventBus.addHandler(ValueChangeEvent.getType(), handler); 076 } 077 078 /** 079 * @see com.google.gwt.event.shared.HasHandlers#fireEvent(com.google.gwt.event.shared.GwtEvent) 080 */ 081 public void fireEvent(GwtEvent<?> event) { 082 083 m_eventBus.fireEvent(event); 084 } 085 086 /** 087 * @see org.opencms.gwt.client.ui.input.I_CmsStringModel#getId() 088 */ 089 public String getId() { 090 091 return m_id; 092 } 093 094 /** 095 * @see org.opencms.gwt.client.ui.input.I_CmsStringModel#getValue() 096 */ 097 public String getValue() { 098 099 return m_value; 100 } 101 102 /** 103 * @see org.opencms.gwt.client.ui.input.I_CmsStringModel#setValue(java.lang.String, boolean) 104 */ 105 public void setValue(String value, boolean notify) { 106 107 if (!m_active) { 108 m_active = true; 109 try { 110 111 boolean changed = !Objects.equal(value, m_value); 112 m_value = value; 113 if (notify && changed) { 114 ValueChangeEvent.fire(this, value); 115 } 116 } finally { 117 m_active = false; 118 } 119 } 120 121 } 122 123}