001// Copyright 2007-2013 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.components; 016 017import org.apache.tapestry5.*; 018import org.apache.tapestry5.annotations.Environmental; 019import org.apache.tapestry5.annotations.Mixin; 020import org.apache.tapestry5.annotations.Parameter; 021import org.apache.tapestry5.corelib.mixins.DiscardBody; 022import org.apache.tapestry5.corelib.mixins.RenderDisabled; 023import org.apache.tapestry5.corelib.mixins.RenderInformals; 024import org.apache.tapestry5.ioc.annotations.Inject; 025import org.apache.tapestry5.services.ComponentDefaultProvider; 026import org.apache.tapestry5.services.javascript.JavaScriptSupport; 027 028/** 029 * A radio button (i.e., <input type="radio">). Radio buttons <strong>must</strong> operate within a 030 * {@link RadioContainer} (normally, the {@link RadioGroup} component). 031 * <p/> 032 * If the value parameter is not bound, then the default value is a property of the container component whose name 033 * matches the Radio component's id. 034 * 035 * @tapestrydoc 036 * @see RadioGroup 037 * @see Form 038 * @see Select 039 */ 040public class Radio implements Field 041{ 042 @Environmental 043 private RadioContainer container; 044 045 /** 046 * The user presentable label for the field. If not provided, a reasonable label is generated from the component's 047 * id, first by looking for a message key named "id-label" (substituting the component's actual id), then by 048 * converting the actual id to a presentable string (for example, "userId" to "User Id"). 049 */ 050 @Parameter(defaultPrefix = BindingConstants.LITERAL) 051 private String label; 052 053 /** 054 * The value associated with this radio button. This is used to determine which radio button will be selected when 055 * the page is rendered, and also becomes the value assigned when the form is submitted. 056 */ 057 @Parameter(required = true, principal = true, autoconnect = true) 058 private Object value; 059 060 @Inject 061 private ComponentDefaultProvider defaultProvider; 062 063 @Inject 064 private ComponentResources resources; 065 066 @SuppressWarnings("unused") 067 @Mixin 068 private RenderInformals renderInformals; 069 070 @SuppressWarnings("unused") 071 @Mixin 072 private RenderDisabled renderDisabled; 073 074 @SuppressWarnings("unused") 075 @Mixin 076 private DiscardBody discardBody; 077 078 @Inject 079 private JavaScriptSupport jsSupport; 080 081 private String clientId; 082 083 private String controlName; 084 085 /** 086 * If true, then the field will render out with a disabled attribute (to turn off client-side behavior). Further, a 087 * disabled field ignores any value in the request when the form is submitted. 088 */ 089 @Parameter("false") 090 private boolean disabled; 091 092 String defaultLabel() 093 { 094 return defaultProvider.defaultLabel(resources); 095 } 096 097 /** 098 * Returns the control name provided by the containing {@link org.apache.tapestry5.RadioContainer}. 099 */ 100 public String getControlName() 101 { 102 return controlName; 103 } 104 105 public String getLabel() 106 { 107 return label; 108 } 109 110 /** 111 * Returns true if this component has been expressly disabled (via its disabled parameter), or if the 112 * {@link RadioContainer container} has been disabled. 113 */ 114 public boolean isDisabled() 115 { 116 return disabled || container.isDisabled(); 117 } 118 119 public String getClientId() 120 { 121 return clientId; 122 } 123 124 void beginRender(MarkupWriter writer) 125 { 126 String value = container.toClient(this.value); 127 128 clientId = jsSupport.allocateClientId(resources); 129 controlName = container.getControlName(); 130 131 writer.element("input", 132 "type", "radio", 133 "id", clientId, 134 "name", controlName, 135 "value", value); 136 137 if (container.isSelected(this.value)) 138 writer.attributes("checked", "checked"); 139 } 140 141 void afterRender(MarkupWriter writer) 142 { 143 writer.end(); 144 } 145 146 /** 147 * Returns false; the RadioComponent component does not support declarative field validation. 148 */ 149 public boolean isRequired() 150 { 151 return false; 152 } 153}