001    // Copyright 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.wml;
016    
017    import org.apache.hivemind.HiveMind;
018    import org.apache.tapestry.IForm;
019    import org.apache.tapestry.IMarkupWriter;
020    import org.apache.tapestry.IRequestCycle;
021    import org.apache.tapestry.form.FormEventType;
022    import org.apache.tapestry.form.FormSupportImpl;
023    
024    /**
025     * Subclass of {@link org.apache.tapestry.form.FormSupportImpl} that
026     * adjusts the output markup to conform to WML.
027     * 
028     * @author Howard M. Lewis Ship
029     * @since 4.0
030     */
031    public class GoFormSupportImpl extends FormSupportImpl
032    {
033    
034        public GoFormSupportImpl(IMarkupWriter writer, IRequestCycle cycle,
035                IForm form)
036        {
037            super(writer, cycle, form);
038        }
039    
040        protected void writeTag(IMarkupWriter writer, String method, String url)
041        {
042            writer.begin("go");
043            writer.attribute("method", method);
044            writer.attribute("href", url);
045        }
046    
047        protected void writeHiddenFields()
048        {
049            // The super-implementation writes a <div> tag that's not
050            // valid as WML.
051            
052            writeHiddenFieldList(getHiddenFieldWriter());
053        }
054        
055        protected void writeHiddenField(IMarkupWriter writer, String name,
056                String id, String value)
057        {
058            writer.beginEmpty("postfield");
059            writer.attribute("name", name);
060    
061            if (HiveMind.isNonBlank(id)) writer.attribute("id", id);
062    
063            writer.attribute("value", value);
064            writer.println();
065        }
066    
067        public void addEventHandler(FormEventType type, String functionName)
068        {
069            throw new UnsupportedOperationException(
070                    "addEventHandler() not supported for WML Go component.");
071        }
072    
073        protected void emitEventManagerInitialization()
074        {
075        }
076    }