春季形式：选择-多个默认情况下不选择第一个选项

Question

I have been working on a Spring project that makes use of the Spring form taglib ( http://www.springframework.org/tags/form ).

I am using some multiple select boxes to indicate some options (Country, factory,...)
When I pass an entire list to the select - all is well: the first option of the select list is selected by default. However, when a user is from a specific country, the list is filtered and only his country is shown. In this case the first element is not selected by default.

JSP page:

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<form:select path="countryValues" multiple="true" size="9" style="width:192px;" cssErrorClass="field-error">
    <form:options items="${command.countries}" itemValue="countryCode" itemLabel="correctDisplayString"/>                                       
</form:select>

Command.java

public List<CountryMaster> getCountries() {
    return countries;
}

public void setCountries(List<CountryMaster> countries) {
    this.countries = countries;
}

Controller.java

@RequestMapping(value = "/overview", method = RequestMethod.GET)
public String overview(HttpServletRequest request, Model model) {
    Attrs attrs = getAttrs(request);
    UserLocale.initUser(getUser(request));
    User user = UserLocale.getUser();
    List<FactoryMaster> factoryList = getFactoryList(attrs);
    List<CountryMaster> countryList = getCountryList(attrs);
    Command command = initCommand(attrs);
    model.addAttribute(command);
    if(user.hasRole(User.NORMAL)&& user.getCountryCode() != null){

        if(countries == null){
             countries=  getDaoBuilder().getDaoCountry().countryMap();               
         }

        String isoCode = countries.get(user
                .getCountryCode());
        List<CountryMaster> buffer = new ArrayList<CountryMaster>();
        for(CountryMaster i : countryList){
            if(isoCode.equalsIgnoreCase(i.getIsoCode())){
                buffer.add(i);                  
            }
        }
        System.out.println("List size: "+buffer.size());
        command.setCountries(buffer);       
    }
    else{
        command.getCountries().addAll(getCountryList(attrs));
    }

    command.getModels().addAll(getModelList(attrs));
    command.setBrands(getBrandList(attrs));
    return "/reporting/overview";
}
private List<CountryMaster> getCountryList(Attrs attrs) {
    List<CountryMaster> result = new ArrayList<CountryMaster>();
    CountryMaster ct = new CountryMaster(CountryMaster.ISO_COUNTRY_JOKER, 00);
    ct.setDescription("ALL");
    result.add(ct);
    result.addAll(attrs.countryList);
    return result;
}

On the HTML page, I can see in other lists that the first element has the attribute selected="selected" . Anybody have any idea why this is not the case when I manipulate my list? Or does anyone know what is resposible for this selected attribute allocation? (Is this javascript, java attribute,...?)

Thanks in advance!

Answer 1

Turns out the value of the listbox can be set: this piece of code made it quite an easy fix:

public String overview(HttpServletRequest request, Model model) {
Attrs attrs = getAttrs(request);
UserLocale.initUser(getUser(request));
User user = UserLocale.getUser();
List<FactoryMaster> factoryList = getFactoryList(attrs);
List<CountryMaster> countryList = getCountryList(attrs);
Command command = initCommand(attrs);
model.addAttribute(command);
if(user.hasRole(User.NORMAL)&& user.getCountryCode() != null){

    if(countries == null){
         countries=  getDaoBuilder().getDaoCountry().countryMap();               
     }

    String isoCode = countries.get(user
            .getCountryCode());
    List<CountryMaster> buffer = new ArrayList<CountryMaster>();
    for(CountryMaster i : countryList){
        if(isoCode.equalsIgnoreCase(i.getIsoCode())){
            buffer.add(i);                  
        }
    }
    System.out.println("List size: "+buffer.size());
    command.setCountries(buffer); 

    // FIXED SELECTION OF ELEMENT
    command.setFactoryValues(new String[]{isoCode});
    // FIXED SELECTION OF ELEMENT   

}
else{
    command.getCountries().addAll(getCountryList(attrs));
}

    command.getModels().addAll(getModelList(attrs));
    command.setBrands(getBrandList(attrs));
    return "/reporting/overview";
}

This way, you set the value of the listbox using code, and when the page is opened - the value is already there, making it selected by default.