001 // Copyright 2004, 2005 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.tapestry.html;
016
017 import org.apache.tapestry.AbstractComponent;
018 import org.apache.tapestry.IMarkupWriter;
019 import org.apache.tapestry.IRequestCycle;
020 import org.apache.tapestry.services.ResponseBuilder;
021
022 /**
023 * The body of a Tapestry page. This is used since it allows components on the page access to an
024 * initialization script (that is written the start, just inside the <body> tag). This is
025 * currently used by {@link Rollover}and {@link Script}components. [ <a
026 * href="../../../../../ComponentReference/Body.html">Component Reference </a>]
027 *
028 * @author Howard Lewis Ship
029 */
030
031 public abstract class Body extends AbstractComponent
032 {
033
034 protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
035 {
036 IMarkupWriter nested = writer.getNestedWriter();
037
038 renderBody(nested, cycle);
039
040 getRenderWorker().renderBody(cycle, this);
041
042 // This is a little tricky, if we didn't call this manually
043 // now the page would never be able to have any javascript related
044 // render workers actually work because the javascript output would
045 // essentially be non writable
046
047 getRenderWorker().renderComponent(cycle, getPage());
048
049 // Start the body tag.
050 writer.println();
051 writer.begin(getElement());
052
053 renderInformalParameters(writer, cycle);
054
055 renderIdAttribute(writer, cycle);
056
057 writer.println();
058
059 // Write the page's scripting. This is included scripts
060 // and dynamic JavaScript.
061
062 getBuilder().writeBodyScript(writer, cycle);
063
064 // Close the nested writer, which dumps its buffered content
065 // into its parent.
066
067 nested.close();
068
069 // Any initialization should go at the very end of the document
070 // just before the close body tag. Older version of Tapestry
071 // would create a window.onload event handler, but this is better
072 // (it doesn't have to wait for external images to load).
073
074 getBuilder().writeInitializationScript(writer);
075
076 writer.end(); // <body>
077 }
078
079 /**
080 * Parameter.
081 */
082 public abstract String getElement();
083
084 public abstract ResponseBuilder getBuilder();
085 }