为什么我的第二个下拉菜单没有被填充？

我正在使用JSP，STRUTS2，AJAX，jQuery和MySQL来填充依赖下拉列表。我想知道为什么我的第二个下拉列表没有被填充？请让我知道我在这里失踪。为什么我的第二个下拉菜单没有被填充？

AjaxJsonAction.java

package com.action; 

import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.ResultSet; 
import java.util.ArrayList; 
import java.util.LinkedHashMap; 
import java.util.List; 
import java.util.Map; 

import org.json.JSONArray; 


import com.opensymphony.xwork2.Action; 
public class AjaxJsonAction implements Action{ 

    private Map<String, String> stateMap = new LinkedHashMap<String, String>(); 
    private String dummyMsg; 
    //Parameter for Jquery 
    private String countryName; 
    private String eventName; 
// 
// private Map<String, String> eventList = new LinkedHashMap<String, String>(); 
// private Map<String, String> eventDateList = new LinkedHashMap<String, String>(); 
    private ArrayList<Event> eventList; 
    private ArrayList<EventShow> eventShowList; 
    private Map<String, String> edList = new LinkedHashMap<String, String>(); 

    public Map<String, String> getStateMap() { 
     return stateMap; 
    } 

    public String getDummyMsg() { 
     return dummyMsg; 
    } 

    public String getCountryName() { 
     return countryName; 
    } 


    public void setStateMap(Map<String, String> stateMap) { 
     this.stateMap = stateMap; 
    } 

    public void setDummyMsg(String dummyMsg) { 
     this.dummyMsg = dummyMsg; 
    } 

    public void setCountryName(String countryName) { 
     this.countryName = countryName; 
    } 

// public Map<String, String> getEventList() { 
//  return eventList; 
// } 
// public void setEventList(Map<String, String> eventList) { 
//  this.eventList = eventList; 
// } 
// 
// public Map<String, String> getEventDateList() { 
//  return eventDateList; 
// } 
// public void setEventDateList(Map<String, String> eventDateList) { 
//  this.eventDateList = eventDateList; 
// } 
    public String getEventName() { 
     return eventName; 
    } 

    public void setEventName(String eventName) { 
     this.eventName = eventName; 
    } 
    public ArrayList<Event> getEventList() { 
     return eventList; 
    } 

    public void setEventList(ArrayList<Event> eventList) { 
     this.eventList = eventList; 
    } 

    public ArrayList<EventShow> getEventShowList() { 
     return eventShowList; 
    } 

    public void setEventShowList(ArrayList<EventShow> eventShowList) { 
     this.eventShowList = eventShowList; 
    } 

public Map<String, String> getedList() { 
    return edList; 
} 
public void setedList(Map<String, String> edList) { 
    this.edList = edList; 
} 


private List<EventShow> eventShows; 

public List<EventShow> getEventShows() { return eventShows; } 

    public String execute() { 

//  dummyMsg = "Ajax action Triggered"; 
//  return SUCCESS; 
     System.out.println("inside execute."); 
     populateEvent(); 
     System.out.println("eventList Count="+eventList.size()); 
//  populateShow(eventName); 
     return "success"; 
    } 

    public void populateEvent() { 
     System.out.println("inside populateEvent."); 
     Connection conn = null; 

      try { 
      String URL = "jdbc:mysql://localhost:3306/bookmyshow_dates"; 
      Class.forName("com.mysql.jdbc.Driver"); 
      conn = DriverManager.getConnection(URL, "dra2", "[email protected]"); 
      String sql = "SELECT DISTINCT * FROM EVENTS"; 
//   String sql ="SELECT * FROM user3333"; 
     PreparedStatement ps = conn.prepareStatement(sql); 

      ResultSet rs = ps.executeQuery(); 

      eventList = new ArrayList<Event>(); 
      while (rs.next()) { 
//    eventList.put(rs.getString("EventId"),rs.getString("EventName")); 
       eventList.add(new Event(rs.getInt("EventId"),rs.getString("EventName"))); 
      } 
      } catch (Exception e) { 
//   return "error"; 
      } 
      finally { 
      if (conn != null) { 
       try { 
        conn.close(); 
       } catch (Exception e) { 
       } 
      } 
      } 
      System.out.println("inside populateEvent End."); 

//  return "getEventList"; 
    } 

// public void populateShow(String eventName) { 
// public ArrayList<EventShow> populateShow() { 
// public Map<String, String> populateShow() { 
    public void populateShow() { 
     String eventId="1"; 
     System.out.println("parameter:"+eventId); 
     Connection conn = null; 

      try { 
      String URL = "jdbc:mysql://localhost:3306/bookmyshow_dates"; 
      Class.forName("com.mysql.jdbc.Driver"); 
      conn = DriverManager.getConnection(URL, "dra2", "[email protected]"); 


      String sql="SELECT ShowId,EventDate,\r\n" + 
        "CASE \r\n" + 
        " WHEN DATEDIFF(EventDate,NOW()) = 0 THEN CONCAT('Today',', ',DAY(EventDate),' ',MONTHNAME(EventDate))\r\n" + 
        " WHEN DATEDIFF(EventDate,NOW()) = 1 THEN CONCAT('Tomorrow',', ',DAY(EventDate),' ',MONTHNAME(EventDate))\r\n" + 
        " WHEN DATEDIFF(EventDate,NOW()) > 1 THEN CONCAT(DAYNAME(EventDate),', ',DAY(EventDate),' ',MONTHNAME(EventDate))\r\n" + 
        "END AS EventDay\r\n" + 
        ",es.EventId\r\n" + 
        "FROM EventShows es\r\n" + 
        "INNER JOIN EVENTS e ON es.EventId = e.EventId AND (EventDate>=NOW())\r\n" + 
        "WHERE e.EventId='"+eventId+" ';"; 
//   String sql ="SELECT * FROM user3333"; 
     PreparedStatement ps = conn.prepareStatement(sql); 

      ResultSet rs = ps.executeQuery(); 

      eventShowList = new ArrayList<EventShow>(); 
      while (rs.next()) { 
       eventShowList.add(new EventShow(rs.getInt("ShowId"),rs.getString("EventDay"),rs.getInt("EventId"))); 
//    eventDateList.put(rs.getString("EventId"), rs.getString("EventName")); 
       edList.put(rs.getString("EventId"), rs.getString("EventName")); 
      } 
      } catch (Exception e) { 
//   return "error"; 
      } 
      finally { 
      if (conn != null) { 
       try { 
        conn.close(); 
       } catch (Exception e) { 
       } 
      } 
      } 
System.out.println("eventShowList:"+eventShowList.size()); 
//  JSONArray jsArray = new JSONArray(eventShowList); 

     // Converts JSON string into a List of Product object 
//  List<EventShow> eventShows = ((List<EventShow>) eventShowList); 
//  return eventShowList; 
    } 

}

Event.java

package com.action; 

public class Event { 
    private int eventId; 

    private String eventName; 

    Event(int eventId, String eventName) 
    { 
     this.eventId = eventId; 
     this.eventName = eventName; 
    } 

    public int getEventId() { 
     return eventId; 
    } 
    public void setEventId(int eventId) { 
     this.eventId = eventId; 
    } 
    public String getEventName() { 
     return eventName; 
    } 
    public void setEventName(String eventName) { 
     this.eventName = eventName; 
    } 

}

EventShow.java

package com.action; 

public class EventShow { 

    private int showId; 
    private String eventDate; 
    private int eventId; 

    EventShow(int showId, String eventDate, int eventId) 
    { 
     this.showId = showId; 
     this.eventId = eventId; 
     this.eventDate = eventDate; 
    } 

    public int getshowId() { 
     return showId; 
    } 

    public void setShowId(int showId) { 
     this.showId = showId; 
    } 
    public String getEventDate() { 
     return eventDate; 
    } 

    public void setEventDate(String eventDate) { 
     this.eventDate = eventDate; 
    } 
    public int getEventId() { 
     return eventId; 
    } 
    public void setEventId(int eventId) { 
     this.eventId = eventId; 
    } 

}

struts.xml的

<?xml version="1.0" encoding="UTF-8" ?> 
<!DOCTYPE struts PUBLIC 
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" 
"http://struts.apache.org/dtds/struts-2.0.dtd"> 
<struts> 
<package name="default" extends="json-default"> 

    <action name="getEvents" class="com.action.AjaxJsonAction" > 
     <result name="success">/index.jsp</result> 
     <result name="error">/error.jsp</result> 
    </action> 

    <action name="populateEventDate" class="com.action.AjaxJsonAction" method="populateShow"> 
<!--  <result type="json">/index.jsp</result> --> 
      <result name="success">/index.jsp</result> 
    </action> 

</package> 
</struts>

的web.xml

<?xml version="1.0" encoding="UTF-8"?> 
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> 
    <display-name>Struts2</display-name> 
    <filter> 
    <filter-name>struts2</filter-name> 
    <filter-class> 
      org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class> 
    </filter> 
    <filter-mapping> 
    <filter-name>struts2</filter-name> 
    <url-pattern>/*</url-pattern> 
    </filter-mapping> 
    <welcome-file-list> 
    <welcome-file>index.jsp</welcome-file> 
    </welcome-file-list> 
</web-app>

的index.jsp

<%@ taglib prefix="s" uri="/struts-tags"%> 
<html> 
<head> 
<title>AJAX in Struts 2 using JSON and jQuery</title> 
<script src="js/jquery-1.8.2.js" type="text/javascript"></script> 
<script> 
$(document).ready(function() { 
    $('#country').change(function(event) { 
     var country = $("select#country").val(); 
     $.getJSON('ajaxAction', { 
      countryName : country 
     }, function(jsonResponse) { 
      $('#ajaxResponse').text(jsonResponse.dummyMsg); 
      var select = $('#states'); 
      select.find('option').remove(); 
      $.each(jsonResponse.stateMap, function(key, value) { 
       $('<option>').val(key).text(value).appendTo(select); 
      }); 
     }); 
    }); 

// $('#event').change(function(event) { 
//  var country = $("select#event").val(); 
// //  $.getJSON('<s:url action='populateEventDate'/>', { 
// $.getJSON('populateEventDate', { 
//   eventName : country 
//  }, function(jsonResponse) { 
//   $('#ajaxResponse').text(jsonResponse.dummyMsg); 
//   var select = $('#eventDate'); 
//   select.find('option').remove(); 
//   $.each(jsonResponse.eventDateList, function(key, value) { 
//    $('<option>').val(key).text(value).appendTo(select); 
//   }); 
//  }); 
// //  $.ajax({ 
// //    type: "POST", 
// //    url: "<s:url action='populateEventDate'/>", 
// //    data: {'eventName': country}, 
// //    contentType: "application/json; charset=utf-8", 
// //    dataType: "json", 
// //    success: function(msg) { 
// //     $("#eventDate").get(0).options.length = 0; 
// //     $("#eventDate").get(0).options[0] = new Option("Select event", "-1"); 

// //     $.each(msg.d, function(index, item) { 
// //      $("#eventDate").get(0).options[$("#eventDate").get(0).options.length] = new Option(item.Display, item.Value); 
// //     }); 
// //    }, 
// //    error: function(meg) { 
// //     $("#eventDate").get(0).options.length = 0; 
// //     alert("Failed to load events."+meg); 
// //    } 
// //   }); 
// }); 

$('#event').change(function(event) { 
     var eName = $("select#event").val(); 
//  $.getJSON('populateEventDate', { 
//   eventName : eName 
//  }, function(jsonResponse) { 
//   $('#ajaxResponse').text(jsonResponse.dummyMsg); 
//   var select = $('#eventDate'); 
//   select.find('option').remove(); 
//   $.each(jsonResponse.stateMap, function(key, value) { 
//    $('<option>').val(key).text(value).appendTo(select); 
//   }); 
//  }); 

     $.ajax({ 
      type:'POST', 
      dataType:'json', 
//   url:'populateEventDate?eventName='+eName, 
     url: "<s:url action='populateEventDate'/>", 
     data: {'eventName': eName}, 
//   dataType: "text", 
     contentType: "application/json; charset=utf-8", 

      success: function(jsonResponse) { 
       $('#ajaxResponse').text(jsonResponse.dummyMsg); 
       var select = $('#eventDate'); 
       select.find('option').remove(); 
       $.each(jsonResponse.eventDateList, function(key, value) { 
       $('<option>').val(key).text(value).appendTo(select); 
       }); 
           }, 
      error: function(jsonResponse) { 
       $("#eventDate").get(0).options.length = 0; 
       alert("Failed to load events."+jsonResponse); 
      } 
     }); 
    }); 
}); 
</script> 
</head> 
<body> 
    <h3>AJAX calls to Struts 2 using JSON and jQuery</h3> 

    <br /> 
    <br /> 
    <s:select name="event" id="event" list="eventList" listKey="eventId" 
      listValue="eventName" headerKey="0" headerValue="Event" 
      label="Select a event" /> 
    <br /> 
    <br /> 
    <s:select id="eventDate" name="eventDate" list="{'Select eventdate'}" 
     label="Select eventdate" /> 

</body> 
</html>

另外，我得到JSON响应作为函数NULL： $('#event').change(function(event)。

来源

2014-06-18 vipin

您是否期待其中一个影响另一个的人口？并且都应该通过JSON动作填充？ – gcalex5

gcalex5 - 其相关的下拉菜单。而且这两个都不应该通过JSON动作填充，只有应该通过JSON填充的子级下拉列表。 – vipin

我会推荐使用'sj：select'标签，然后使用和onChangeTopics选项来让另一个依赖另一个，然后给孩子一个和href标签到你的json标签。当然，如果你可以使用struts2 jquery插件和struts2 json插件。如果你想我可以给你和我的代码摘录 – gcalex5

您需要进行一些更正。

步骤1：在struts.xml文件

<action name="populateEventDate" class="com.action.AjaxJsonAction" method="populateShow"> 
    <result type="json">/index.jsp</result> 
</action>

步骤2：在AjaxJsonAction.java

public String populateShow() { 
    edList.put("1", "Monday");// Fill this map with your database values 
    return "success"; 
}

步骤3：在index.jsp - >使用jQuery JS从CDN和下面使用代码

<script src="//code.jquery.com/jquery-1.11.0.min.js"></script> 
<script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script> 

<script type="text/javascript"> 
$(document).ready(function() { 
    $('#event').change(function(event) { 
     var event = $("select#event").val(); 

     $.getJSON('populateEventDate', { 
      eventName : event 
     }, function(jsonResponse) { 
      $('#ajaxResponse').text(jsonResponse.dummyMsg); 
      var select = $('select#eventDate'); 
      select.find('option').remove(); 
      $.each(jsonResponse.edList, function(key, value) { 
       $('<option>').val(key).text(value).appendTo(select); 
      }); 
     }); 
    }); 
}); 

</script>

如果您还有其他错误，请回复我。

来源

2014-06-24 07:10:11

感谢帕特的建议。不过，我从您的文章得到了主意，并有修改struts.xml中包括以下行动

<action name="getEvents" class="qBook.AjaxJsonAction" > 
     <result name="success">/index.jsp</result> 
    </action> 
    <action name="ajaxAction" class="qBook.AjaxJsonAction" method="TestABC"> 
     <result type="json">/index.jsp</result> 
    </action>

首先行动 - 获得在网页加载和第二动作第一个下拉数据得到第一的数据基于选择的值在AJAX调用的帮助下下来。您的评论真的帮了我，再次'谢谢你'。

来源

2014-07-03 06:10:29 vipin

为什么我的第二个下拉菜单没有被填充？

回答

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