001 // Copyright 2011 The Apache Software Foundation
002 //
003 // Licensed under the Apache License, Version 2.0 (the "License");
004 // you may not use this file except in compliance with the License.
005 // You may obtain a copy of the License at
006 //
007 // http://www.apache.org/licenses/LICENSE-2.0
008 //
009 // Unless required by applicable law or agreed to in writing, software
010 // distributed under the License is distributed on an "AS IS" BASIS,
011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012 // See the License for the specific language governing permissions and
013 // limitations under the License.
014
015 package org.apache.tapestry5.corelib.mixins;
016
017 import org.apache.tapestry5.BindingConstants;
018 import org.apache.tapestry5.ComponentResources;
019 import org.apache.tapestry5.EventConstants;
020 import org.apache.tapestry5.Link;
021 import org.apache.tapestry5.annotations.AfterRender;
022 import org.apache.tapestry5.annotations.Import;
023 import org.apache.tapestry5.annotations.InjectContainer;
024 import org.apache.tapestry5.annotations.Parameter;
025 import org.apache.tapestry5.corelib.components.Zone;
026 import org.apache.tapestry5.internal.util.CaptureResultCallback;
027 import org.apache.tapestry5.ioc.annotations.Inject;
028 import org.apache.tapestry5.json.JSONObject;
029 import org.apache.tapestry5.services.javascript.InitializationPriority;
030 import org.apache.tapestry5.services.javascript.JavaScriptSupport;
031
032 /**
033 * <p>
034 * This mixin periodically refreshs a @{link org.apache.tapestry5.corelib.components.Zone zone}
035 * by triggering an event on the server using ajax requests.
036 * </p>
037 *
038 * <b>Note: </b> This mixin is only meant for a @{link org.apache.tapestry5.corelib.components.Zone zone}
039 * @tapestrydoc
040 */
041 @Import(library = "zone-refresh.js")
042 public class ZoneRefresh
043 {
044 /**
045 * Period between two consecutive refreshes (in seconds)
046 */
047 @Parameter(required = true, defaultPrefix = BindingConstants.LITERAL)
048 private int period;
049
050 /**
051 * Context passed to the event
052 */
053 @Parameter
054 private Object[] context;
055
056 @InjectContainer
057 private Zone zone;
058
059 @Inject
060 private JavaScriptSupport javaScriptSupport;
061
062 @Inject
063 private ComponentResources resources;
064
065 public ZoneRefresh()
066 {
067 }
068
069 //For testing purpose
070 ZoneRefresh(Object [] context, ComponentResources resources, JavaScriptSupport javaScriptSupport, Zone zone)
071 {
072 this.context = context;
073 this.resources = resources;
074 this.javaScriptSupport = javaScriptSupport;
075 this.zone = zone;
076 }
077
078 @AfterRender
079 void addJavaScript()
080 {
081 JSONObject params = new JSONObject();
082
083 params.put("period", period);
084 params.put("id", zone.getClientId());
085 params.put("URL", createEventLink());
086
087 javaScriptSupport.addInitializerCall(InitializationPriority.LATE, "zoneRefresh", params);
088 }
089
090 private Object createEventLink()
091 {
092 Link link = resources.createEventLink("zoneRefresh", context);
093 return link.toAbsoluteURI();
094 }
095
096 Object onZoneRefresh()
097 {
098 CaptureResultCallback<Object> callback = new CaptureResultCallback<Object>();
099 resources.triggerEvent(EventConstants.REFRESH, context, callback);
100
101 if(callback.getResult() != null){
102 return callback.getResult();
103 }
104
105 return zone.getBody();
106 }
107
108 }