Wicket - DropDownChoice POJO to Property Model

Question

Little problem with DropDownChoice. I build a DropDownChoice with a list of Object. Take for example:

public MyClass 
  private String code;
  private String description;
[...]

than take another Object

public FormModelObject
   private String code;

I can easly build the DropDownChoice selecting what show (description property) and what obtain (code property) using ChoiceRender.

Unfortunally the DropDownChoice return the entire Object (MyClass) and I cannot set the property Code inside FormModelObject (it simply launch a toString() method on MyClass).

How can I obtain it without using Ajax?

Thanks

Why would you? You have backing Model for the DDC that implements IModel and can simply access the object and the code property from it? — bert, Aug 22 '12 at 13:20

score 1 · Answer 1 · answered Aug 22 '12 at 14:02

Try with model chaining. You should replace variable code of the form with a property model built like this:

//this is the model of your DropDownChoice
Model<MyClass> myModel = new Model<MyClass>();
//...

PropertModel myCode = new PropertModel(myModel, "code");

Now use myCode instead of code in your form.

score 1 · Accepted Answer · answered Aug 22 '12 at 19:00

Well, you could override method onModelChanged() of DropDownChoice and update residenceZipCode with the new value. Something like :

DropDownChoice<City> drop = new DropDownChoice<City>("residenceZipCode",new Model(), cityList,new ChoiceRenderer<City>("name", "zipcode")){
     onModelChanged(){
       String newZipCode =  (String)PropertyResolver.getValue("zipCode",getModelObject());
       PropertyResolver.setValue("residenceZipCode", res, newZipCode, new  PropertyResolverConverter());
     }

};

DropDownChoice must have its own model.

score 1 · Answer 3 · answered Aug 23 '12 at 05:57

Take a look at DDC's type argument: In your case it's City, thus the DDC works with City objects.

If you don't want that, change the type and the compiler will guide you the way:

DropDownChoice<String> drop = new DropDownChoice<String>("residenceZipCode",zipCodesList,new CityChoiceRenderer());

class CityChoiceRenderer implements IChoiceRenderer<String> {
  Object getDisplayValue(String zipCode) {
    return zipCodeToName(zipCode);
  }

  String getIdValue(String zipCode, int index) {
    return zipCode;
  }
}

score 0 · Answer 4 · answered Aug 22 '12 at 14:25

Its bettere to write some code:

    class City {
      private String zipCode;
      private String name;
    }

    class Residence {
      private String residenceZipCode;
    }

protected Residence res;

public ResidenceForm() {
  super("form", new CompoundPropertyModel<Residence>(res));

  List<City> cityList = someManager().loadAllCity();

  DropDownChoice<City> drop = new DropDownChoice<City>("residenceZipCode",cityList,new ChoiceRenderer<City>("name", "zipcode"));
add(drop);

Now. I cannot change Residence or City and I cannot write code inside onSubmit button's method.

What I want is zipcode inside Residence. What I obtain now is the equivalent of City.toString()

Wicket - DropDownChoice POJO to Property Model

4 Answers4