     filters: {}
     onFilter: Function.prototype
     onChoose: Function.prototype
+
+  componentWillMount: ->
+    # refs for the choices
+    @choiceButtons = []
 
   getFilteredChoices: ->
     for choiceID in @props.task.choicesOrder

            <button
              autoFocus={choiceID is @props.focusedChoice}
              key={choiceID + i}
              type="button"
              className="survey-task-chooser-choice-button #{'survey-task-chooser-choice-button-chosen' if chosenAlready}"
              onClick={@props.onChoose.bind null, choiceID}

      3

  render: ->
    @choiceButtons = []

    filteredChoices = @getFilteredChoices()

    thumbnailSize = @whatSizeThumbnails filteredChoices
