Question

I would still need some help with my dynamic selectlist.

I have the sript:

function getMains(element) {
var subjectgroup = element.value;

  var select_element;

  select_element = '#mains';


$(select_element).html('');
$(select_element).append($("<option></option>").attr("value","none").html(""));
 //   $(select_element).append($("<option></option>").attr("value","all").html(""));
   if (element.value==''||element.value=='none'||element.value=='all')
  return;
 $.ajax({
  type: 'GET',
  url: 'getmainsubjects.html',
  dataType: 'json',
  data: ({id:data}),
  success: function(data) {
    $.each(function(data) {
      if (!subjectgroup) {
                                                                                                                                      $(select_element).append($("                                                                  <option>").attr("value",data.id,"items",data).html(data.description));
   } else {
    $(select_element).append($("<option>").attr("value",data.id,"items",data).html(data.description));
}

    });
  },
  error: function(data) {
    //alert("This failed!");
       }
     });

   }  

 $('select#subjectgroups').ready(function(){
  $("select#subjectgroups").find("option").each(function(i) {
  if ($(this).val()!='all'&&$(this).val()!='none') {
    $(this).append( " " + $(this).val() );
  }
});

});

   $('select#mains').ready(function(){
  $("select#mains").find("option").each(function(i) {
    if ($(this).val()!='all'&&$(this).val()!='none') {
     $(this).append( " " + $(this).val() );
    }
 });
});

And the method:

@RequestMapping(method = RequestMethod.GET, params="id", value = "/getmainsubjects")
     @ResponseBody
   public String getMainSubjects( @RequestParam("id") int id) {


    List<MainSubjectsSimple> mains = database.getMainSubjectsSimple(id,   Localization.getLanguage());
    //System.out.println(mains.size());
    HashMap hm = new HashMap();



     for (MainSubjectsSimple mss: mains) {
        try {

            hm.put("id",mss.getId());
            hm.put("description", mss.getDescription());

        } catch (NoSuchMessageException e) {
            //hm.add(Integer.valueOf(mss.getId().toString(), translate(mss.getTranslationCode(),new Locale("fi")));
        }
    }
    String json = null;
    String _json = null;

    try {
        _json = HtmlEntityEncoder.encode(JsonUtils.javaToStr(hm));

    } catch (Exception e) {

    }
    return _json;
}

I think I’m not looping the right values. Mains selectlist should be populated based on other selectlist so that the object’s id is the value and description the label. Right now calling the url written in script returns only first object as json, not all of them, and the objects are not shown in mains selectlist.

Answer 1

You are putting the same keys over and over again to the Map hm:

HashMap hm = new HashMap();

 for (MainSubjectsSimple mss: mains) {
    try {

        hm.put("id",mss.getId());
        hm.put("description", mss.getDescription());

    } catch (NoSuchMessageException e) {
        //hm.add(Integer.valueOf(mss.getId().toString(),

translate(mss.getTranslationCode(),new Locale(“fi”)));
}
}

You need to use different keys for each entry in mains or use a collection (e.g. ArrayList) of Maps. An example of the latter:

List hms = new ArrayList();

     for (MainSubjectsSimple mss: mains) {
        try {
            HashMap hm = new HashMap();

            hm.put("id",mss.getId());
            hm.put("description", mss.getDescription());

            hms.add(hm);

        } catch (NoSuchMessageException e) {
            //hm.add(Integer.valueOf(mss.getId().toString(), translate(mss.getTranslationCode(),new Locale("fi")));
        }
    }

    ...

    try {
        _json = HtmlEntityEncoder.encode(JsonUtils.javaToStr(hms));

    } catch (Exception e) {

    }

I’m not familiar with the utils (JsonUtils) you are using so this might not work directly but the principle is the same anyways.