JSF h:selectManyCheckbox inside ui:repeat via Map entry

Question

我遇到了问题，当我将值作为 String 放入 <ui:repeat> 内的 List<String> 时，当我按下按钮时，我看到 List<String> 只包含 ui:repeat 的最后一个元素的记录。

<ui:repeat value="#{util:toList(test.mapQestionsWithAnswers)}" var="entry">
                <h:inputHidden value="#{entry.key.questionId}" />
                <h:outputText value="#{entry.key.question}"
                    rendered="#{not empty entry.value}" />
                <p:selectManyCheckbox value="#{test.questionAnswerList}"
                    layout="pageDirection">
                    <f:selectItems value="#{entry.value}" var="ans"
                        itemValue="#{entry.key.questionId} #{ans.answer.answerId}"
                        itemLabel="${ans.answer.answer}" />
                </p:selectManyCheckbox>
            </ui:repeat>

来自 Baluscanswer How to show hashmap values in jsf? 的 util:toList 的想法

//已更新 我在不使用地图的情况下重写了这段代码

<ui:repeat value="${test.questionList}" var="question">
                <h:outputText value="#{question.question}"
                    rendered="#{not empty question}" />
                <p:selectManyCheckbox value="#{test.questionAnswerList}"
                    layout="pageDirection">
                    <f:selectItems value="#{question.questionAnswers}" var="ans"
                        itemValue="#{ans.questionAnswerIdentifer.questionId} #{ans.questionAnswerIdentifer.answerId}"
                        itemLabel="#{ans.answer.answer}" />
                </p:selectManyCheckbox>
            </ui:repeat>

但这对我没有帮助，我可以进入List<String>，只需将<ui:repeat/> 中最后一个问题的问题答案配对。好像每次迭代之后 questionAnswerList 都变空了

//好吧，我看了一些文章Primefaces ManyCheckbox inside ui:repeat calls setter method only for last loop

我决定使用地图地图>

但在这部分错误ClassCastException String cannot be cast to List

public List<String> getQuestionAnswerList() {
    // return questionAnswerList;
    List<String> selectedQuestionAnswer = new ArrayList<String>();
    if (!selectedItems.isEmpty()) {
        Set<Long> idsSet = selectedItems.keySet();
        for(Long questionId : idsSet){              
            List<String> questionAnswerPair = selectedItems.get(questionId);
            selectedQuestionAnswer.addAll(questionAnswerPair);
        }
    }
    return selectedQuestionAnswer;
}
<p:selectManyCheckbox value="#{test.selectedItems[question.questionId]}"
                    layout="pageDirection">
                    <f:selectItems value="#{question.questionAnswers}" var="ans"
                        itemValue="#{ans.questionAnswerIdentifer.questionId} #{ans.questionAnswerIdentifer.answerId}"
                        itemLabel="#{ans.answer.answer}" />
                </p:selectManyCheckbox> 

如何在List<String> 中获取所有选择的值？

Answer 1

您可以制作一个映射（例如称为myMap），其中键为entry.key，值将是与questionAnswerList 相同类型的列表

类似

<p:selectManyCheckbox value="#{test.myMap[entry.key].questionAnswerList}"
    layout="pageDirection">
    <f:selectItems value="#{entry.value}" var="ans"
        itemValue="#{entry.key.questionId} #{ans.answer.answerId}"
        itemLabel="${ans.answer.answer}" />
</p:selectManyCheckbox>