001// Copyright 2010, 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 015package org.apache.tapestry5.corelib.mixins; 016 017import org.apache.tapestry5.Block; 018import org.apache.tapestry5.ComponentResources; 019import org.apache.tapestry5.MarkupWriter; 020import org.apache.tapestry5.annotations.AfterRender; 021import org.apache.tapestry5.annotations.BeginRender; 022import org.apache.tapestry5.annotations.Events; 023import org.apache.tapestry5.ioc.annotations.Inject; 024 025/** 026 * This mixin triggers event notifcations to identify when it enters 027 * the {@link BeginRender} and {@link AfterRender} render phases. 028 * The {@link MarkupWriter} is passed as the event context. The most common use of this 029 * is to handle the "afterRender" event to generate client-side JavaScript for content 030 * just rendered via a {@link Block} (this is a common Ajax use case related to partial 031 * page rendering). 032 * 033 * @since 5.2.0 034 * @tapestrydoc 035 */ 036@Events( 037{ "beginRender", "afterRender" }) 038public class RenderNotification 039{ 040 @Inject 041 private ComponentResources resources; 042 043 void beginRender(MarkupWriter writer) 044 { 045 trigger(writer, "beginRender"); 046 } 047 048 void afterRender(MarkupWriter writer) 049 { 050 trigger(writer, "afterRender"); 051 } 052 053 private void trigger(MarkupWriter writer, String eventName) 054 { 055 resources.triggerEvent(eventName, new Object[] 056 { writer }, null); 057 } 058}