Constructor Detail

• ChoiceProvider

  public ChoiceProvider()

Method Detail

• getDisplayValue

  public abstract String getDisplayValue(T object)

  Get the value for displaying to an end user.

  Parameters:

  object - the actual object

  Returns:

  the value meant for displaying to an end user

• getIdValue

  public abstract String getIdValue(T object)

  This method is called to get the id value of an object (used as the value attribute of a choice element) The id can be extracted from the object like a primary key, or if the list is stable you could just return a toString of the index.

  Note that the given index can be -1 if the object in question is not contained in the available choices.

  Parameters:

  object - The object for which the id should be generated

  index - The index of the object in the choices list.

  Returns:

  String

• query

  public abstract void query(String term,
           int page,
           Response<T> response)

  Queries application for choices that match the search term and adds them to the response

  Parameters:

  term - search term

  page - requested search term results page

  response - aggregate for matching choices as well as other response options

• toJson

  protected void toJson(T choice,
            org.apache.wicket.ajax.json.JSONWriter writer)
                 throws org.apache.wicket.ajax.json.JSONException

  Converts the specified choice to Json.

  At the very least each choice should contain an id attribute. If no custom rendering function is specified, the text attribute should also be provided

  Example: If mapping a User {Long id, String name} using default rendering the code should look like this:

   toJson(User choice, JSONWriter writer)
   {
          writer.key("id").value(choice.getId()).key("text").value(choice.getName());
   }
   

  Parameters:

  choice - choice to convert

  writer - Json writer that should be used to covnert the choice

  Throws:

  org.apache.wicket.ajax.json.JSONException

• toChoices

  public abstract Collection<T> toChoices(Collection<String> ids)

  Converts a list of choice ids back into application's choice objects. When the choice provider is attached to a single-select component the ids collection will contain exactly one id, and a collection containing exactly one choice should be returned.

  Parameters:

  ids - collection containing choice ids

  Returns:

  collection containing application choice objects

• detach

  public void detach()

  Specified by:

  detach in interface org.apache.wicket.model.IDetachable