JSF 2 radio buttons example

时间:2022-03-19 05:23:01

In JSF, “h:selectOneRadio” tag is used to render a set of HTML input element of type “radio“, and format it with HTML table and label tag.

//JSF...
<h:selectOneRadio value="#{user.favColor1}">
<f:selectItem itemValue="Red" itemLabel="Color1 - Red" />
<f:selectItem itemValue="Green" itemLabel="Color1 - Green" />
<f:selectItem itemValue="Blue" itemLabel="Color1 - Blue" />
</h:selectOneRadio>
//HTML output...
<table>
<tr>
<td>
<input type="radio" name="j_idt6:j_idt8" id="j_idt6:j_idt8:0" value="Red" />
<label for="j_idt6:j_idt8:0"> Color1 - Red</label></td>
<td>
<input type="radio" name="j_idt6:j_idt8" id="j_idt6:j_idt8:1" value="Green" />
<label for="j_idt6:j_idt8:1"> Color1 - Green</label></td>
<td>
<input type="radio" name="j_idt6:j_idt8" id="j_idt6:j_idt8:2" value="Blue" />
<label for="j_idt6:j_idt8:2"> Color1 - Blue</label>
</td>
</tr>
</table>

JSF 2.0 “h:selectOneRadio” example

A JSF 2.0 example to show the use of “h:selectOneRadio” tag to render radio buttons, and populate the data in 3 different ways :

  • Hardcoded values in “f:selectItem” tag.
  • Generate values with a Map and put it into “f:selectItems” tag.
  • Generate values with an Object array and put it into “f:selectItems” tag, then represent the value with a “var” attribute.

1. Backing Bean

A backing bean to hold the submitted data.

package com.mkyong;

import java.util.LinkedHashMap;
import java.util.Map;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped; @ManagedBean(name="user")
@SessionScoped
public class UserBean{ public String favColor1;
public String favColor2;
public String favColor3; //getter and setter methods //Generated by Map
private static Map<String,Object> color2Value;
static{
color2Value = new LinkedHashMap<String,Object>();
color2Value.put("Color2 - Red", "Red"); //label, value
color2Value.put("Color2 - Green", "Green");
color2Value.put("Color3 - Blue", "Blue");
} public Map<String,Object> getFavColor2Value() {
return color2Value;
} //Generated by Object array
public static class Color{
public String colorLabel;
public String colorValue; public Color(String colorLabel, String colorValue){
this.colorLabel = colorLabel;
this.colorValue = colorValue;
} public String getColorLabel(){
return colorLabel;
} public String getColorValue(){
return colorValue;
} } public Color[] color3List; public Color[] getFavColor3Value() { color3List = new Color[3];
color3List[0] = new Color("Color3 - Red", "Red");
color3List[1] = new Color("Color3 - Green", "Green");
color3List[2] = new Color("Color3 - Blue", "Blue"); return color3List;
} }

2. JSF Page

A JSF page to demonstrate the use “h:selectOneRadio” tag.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
>
<h:body> <h1>JSF 2 radio button example</h1>
<h:form> 1. Hard-coded with "f:selectItem" :
<h:selectOneRadio value="#{user.favColor1}">
<f:selectItem itemValue="Red" itemLabel="Color1 - Red" />
<f:selectItem itemValue="Green" itemLabel="Color1 - Green" />
<f:selectItem itemValue="Blue" itemLabel="Color1 - Blue" />
</h:selectOneRadio> <br /> 2. Generated by Map :
<h:selectOneRadio value="#{user.favColor2}">
<f:selectItems value="#{user.favColor2Value}" />
</h:selectOneRadio> <br /> 3. Generated by Object array and iterate with var :
<h:selectOneRadio value="#{user.favColor3}">
<f:selectItems value="#{user.favColor3Value}" var="c"
itemLabel="#{c.colorLabel}" itemValue="#{c.colorValue}" />
</h:selectOneRadio> <br /> <h:commandButton value="Submit" action="result" />
<h:commandButton value="Reset" type="reset" /> </h:form>
</h:body>
</html>

result.xhtml…

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
>
<h:body> <h1>JSF 2 radio button example</h1> <h2>result.xhtml</h2> <ol>
<li>user.favColor1 : #{user.favColor1}</li>
<li>user.favColor2 : #{user.favColor2}</li>
<li>user.favColor3 : #{user.favColor3}</li>
</ol>
</h:body>
</html>

3. Demo

JSF 2 radio buttons example

When “submit” button is clicked, link to “result.xhtml” and display the submitted radio button values.

JSF 2 radio buttons example

How to select radio button value by default?

In JSF, the radio button values of “f:selectItems” tag is selected if it matched to the “value” of “h:selectOneRadio” tag. In above example, if you set favColor2 to “Red” :

@ManagedBean(name="user")
@SessionScoped
public class UserBean{ public String[] favColor = "Red"; //...

The “favColor2″ radio button, “Red” option is selected by default.