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.form; 016 017 import java.util.HashMap; 018 import java.util.Map; 019 020 import org.apache.hivemind.ApplicationRuntimeException; 021 import org.apache.hivemind.HiveMind; 022 import org.apache.tapestry.IComponent; 023 import org.apache.tapestry.IForm; 024 import org.apache.tapestry.IMarkupWriter; 025 import org.apache.tapestry.IRequestCycle; 026 import org.apache.tapestry.IScript; 027 import org.apache.tapestry.PageRenderSupport; 028 import org.apache.tapestry.TapestryUtils; 029 030 /** 031 * Implements a component that submits its enclosing form via a JavaScript link. [ <a 032 * href="../../../../../ComponentReference/LinkSubmit.html">Component Reference </a>] 033 * 034 * @author Richard Lewis-Shell 035 */ 036 037 public abstract class LinkSubmit extends AbstractSubmit 038 { 039 040 /** 041 * The name of an {@link org.apache.tapestry.IRequestCycle}attribute in which the current 042 * submit link is stored. LinkSubmits do not nest. 043 */ 044 045 public static final String ATTRIBUTE_NAME = "org.apache.tapestry.form.LinkSubmit"; 046 047 protected boolean isClicked(IRequestCycle cycle, String name) 048 { 049 String value = cycle.getParameter(name); 050 051 return HiveMind.isNonBlank(value); 052 } 053 054 public abstract IScript getScript(); 055 056 /** 057 * @see org.apache.tapestry.form.AbstractFormComponent#renderFormComponent(org.apache.tapestry.IMarkupWriter, 058 * org.apache.tapestry.IRequestCycle) 059 */ 060 protected void renderFormComponent(IMarkupWriter writer, IRequestCycle cycle) 061 { 062 boolean disabled = isDisabled(); 063 064 IForm form = getForm(); 065 String name = getName(); 066 067 String hiddenId = cycle.getUniqueId(TapestryUtils 068 .convertTapestryIdToNMToken(getIdParameter())); 069 070 // Store for later access by the FieldLabel (or JavaScript). 071 072 setClientId(hiddenId); 073 074 // Add a hidden field used to identify the link that caused the submission. 075 // Client-side JavaScript will set the value to non-null when the link is clicked, 076 // then force the form to submit. 077 078 form.addHiddenValue(name, hiddenId, ""); 079 080 if (!disabled) 081 { 082 PageRenderSupport pageRenderSupport = TapestryUtils.getPageRenderSupport(cycle, this); 083 084 Map symbols = new HashMap(); 085 symbols.put("form", form); 086 symbols.put("hiddenId", hiddenId); 087 088 getScript().execute(cycle, pageRenderSupport, symbols); 089 090 writer.begin("a"); 091 writer.attribute("href", (String) symbols.get("href")); 092 renderInformalParameters(writer, cycle); 093 } 094 095 renderBody(writer, cycle); 096 097 if (!disabled) 098 writer.end(); 099 100 } 101 102 /** 103 * @see org.apache.tapestry.AbstractComponent#prepareForRender(org.apache.tapestry.IRequestCycle) 104 */ 105 protected void prepareForRender(IRequestCycle cycle) 106 { 107 IComponent outer = (IComponent) cycle.getAttribute(ATTRIBUTE_NAME); 108 109 if (outer != null) 110 throw new ApplicationRuntimeException(FormMessages.linkSubmitMayNotNest(this, outer), 111 this, getLocation(), null); 112 113 cycle.setAttribute(ATTRIBUTE_NAME, this); 114 } 115 116 /** 117 * @see org.apache.tapestry.AbstractComponent#cleanupAfterRender(org.apache.tapestry.IRequestCycle) 118 */ 119 protected void cleanupAfterRender(IRequestCycle cycle) 120 { 121 cycle.removeAttribute(ATTRIBUTE_NAME); 122 } 123 124 /** 125 * Links can not take focus, ever. 126 */ 127 protected boolean getCanTakeFocus() 128 { 129 return false; 130 } 131 132 /** 133 * Returns true; the LinkSubmit's body should render during a rewind, even if the component is 134 * itself disabled. 135 */ 136 protected boolean getRenderBodyOnRewind() 137 { 138 return true; 139 } 140 141 }