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JSF多选列表框

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2023-03-14

以下代码显示如何创建多选择选择框。<h:selectManyListbox>标签呈现一个类型为“select”的HTML输入元素,并指定其大小和多项目。

以下JSF代码 -

<h:selectManyListbox value="#{userData.data}">
   <f:selectItem itemValue="1" itemLabel="Item 1" />
   <f:selectItem itemValue="2" itemLabel="Item 2" />
</h:selectOneListbox>

被渲染成以下HTML代码 -

<select name="j_idt6:j_idt8" size="2" multiple="multiple">  
   <option value="1">Item 1</option>
   <option value="2">Item 2</option>
</select>

实例

以下是文件: index.xhtml 中的代码 -

<?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>
      <h:form>
      Hard-coded with "f:selectItem" : 
       <h:selectManyListbox value="#{user.item}">
         <f:selectItem itemValue="A" itemLabel="Item A" />
         <f:selectItem itemValue="B" itemLabel="Item B" />
         <f:selectItem itemValue="C" itemLabel="Item C" />
       </h:selectManyListbox>
    <br /><br />
      <h:commandButton value="Submit" action="result" />
    <h:commandButton value="Reset" type="reset" />
      </h:form>
    </h:body>
</html>

以下是文件: result.xhtml 中的代码 -

<?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"
      xmlns:c="http://java.sun.com/jsp/jstl/core">
    <h:body>
  Selected:  #{user.itemString}

    </h:body>
</html>

以下是文件: UserBean.java 中的代码 -

package com.yiibai;


import java.io.Serializable;
import java.util.Arrays;
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 implements Serializable{
  public String[] item = {"A", "B"};
  public String[] getItem() {
    return item;
  }

  public void setItem(String[] i) {
    this.item = i;
  }

  public String getItemString() {
    return Arrays.toString(item);
  }
}

SelectManyListBox实例

以下是文件: UserBean.java 中的代码 -

package com.yiibai;


import java.io.Serializable;
import java.util.Arrays;
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 implements Serializable{
  public String[] item = {"A", "B"};
  public String[] getItem() {
    return item;
  }

  public void setItem(String[] i) {
    this.item = i;
  }

  public String getItemString() {
    return Arrays.toString(item);
  }
  //Generated by Object array
  public static class Item{
    public String label;
    public String value;

    public Item(String l, String v){
      this.label = l;
      this.value = v;
    }

    public String getLabel(){
      return label;
    }

    public String getValue(){
      return value;
    }

  }

  public Item[] itemList;

  public Item[] getItemValue() {
    itemList = new Item[3];
    itemList[0] = new Item("Item A", "A");
    itemList[1] = new Item("Item B", "B");
    itemList[2] = new Item("Item C", "C");

    return itemList;
  }

}

以下是文件: index.xhtml 中的代码 -

<?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>
      <h:form>
      Generated by Object array and iterate with var :
       <h:selectManyListbox value="#{user.item}">
         <f:selectItems value="#{user.itemValue}" var="f"
         itemLabel="#{f.label}" itemValue="#{f.value}" />
       </h:selectManyListbox>

    <br /><br />
      <h:commandButton value="Submit" action="result" />
    <h:commandButton value="Reset" type="reset" />
      </h:form>
    </h:body>
</html>

以下是文件: result.xhtml 中的代码 -

<?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"
      xmlns:c="http://java.sun.com/jsp/jstl/core">
    <h:body>
  Selected:  #{user.itemString}

    </h:body>
</html>

通过映射的SelectManyListBox实例

以下是文件: UserBean.java 中的代码 -

package com.yiibai;


import java.io.Serializable;
import java.util.Arrays;
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 implements Serializable{
  public String[] item = {"A", "B"};
  public String[] getItem() {
    return item;
  }

  public void setItem(String[] i) {
    this.item = i;
  }

  public String getItemString() {
    return Arrays.toString(item);
  }
  private static Map<String,Object> itemValue;
  static{
    itemValue = new LinkedHashMap<String,Object>();
    itemValue.put("Item A", "A"); //label, value
    itemValue.put("Item B", "B");
    itemValue.put("Item C", "C");
  }

  public Map<String,Object> getItemValue() {
    return itemValue;
  }

}

以下是文件: index.xhtml 中的代码 -

<?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>
      <h:form>
      Generated by Map :
       <h:selectManyListbox value="#{user.item}">
         <f:selectItems value="#{user.itemValue}" />
       </h:selectManyListbox>
    <br /><br />
      <h:commandButton value="Submit" action="result" />
    <h:commandButton value="Reset" type="reset" />
      </h:form>
    </h:body>
</html>

以下是文件: result.xhtml 中的代码 -

<?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"
      xmlns:c="http://java.sun.com/jsp/jstl/core">
    <h:body>
  Selected:  #{user.itemString}

    </h:body>
</html>