在基于测验的应用程序中使用嵌套的 setOnClickListener 的 RecyclerView

Question

我对基于测验的应用程序的基本功能的实现有疑问。简而言之，我在 ArrayList<Question> 中有“问题”和“答案”（对于此示例，每个 Question 都有自己的 ArrayList<Answer>、3）我曾经在使用 MVVM 管理的片段中填充 RecyclerView 的适配器。

这是我的 onBindViewHolder 函数：

  ...
  
  override fun onBindViewHolder(holder: MyViewHolder, position: Int) {        
 
  ...

    val curQuest = myDataset[position]    
    val shuffledAnswers = curQuest.answers


    holder.ans1.text = shuffledAnswers[0].answer_text
    holder.ans1.setOnClickListener {
        it.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.selected_ans_quiz)
        holder.ans2.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
        holder.ans3.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
    }

    holder.ans2.text = shuffledAnswers[1].answer_text
    holder.ans2.setOnClickListener {
        it.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.selected_ans_quiz)
        holder.ans1.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
        holder.ans3.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
    }

    holder.ans3.text = shuffledAnswers[2].answer_text
    holder.ans3.setOnClickListener {
        it.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.selected_ans_quiz)
        holder.ans2.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
        holder.ans1.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
    }
 }

一切正常，但 select 的答案：如果我 select 第一个问题的答案 (myDataset[0])，[=43] 的视图也会发生变化=]N+0 列表中的元素，其中 N 是由 RecyclerView

加载的项目的最大块数

如何在 RecyclerView 中为每个子元素设置正确的属性而不在 onBindViewHolder 加载的第 N 个元素之后传播？

可以修复还是我必须改变实现方式？

编辑：我刚刚尝试了另一种方法，但结果相同，使用的是接口：

QuizAdapter.kt

  ...
  
  override fun onBindViewHolder(holder: MyViewHolder, position: Int) {        
 
  ...

    val curQuest = myDataset[position]    
    val shuffledAnswers = curQuest.answers


    holder.ans1.text = shuffledAnswers[0].answer_text
    holder.ans1.setOnClickListener {
        mCallback.onClick(shuffledAnswers[0],position,it,holder.ans2,holder.ans3)
    }

    holder.ans2.text = shuffledAnswers[1].answer_text
    holder.ans2.setOnClickListener {
        mCallback.onClick(shuffledAnswers[1],position,it,holder.ans1,holder.ans3)
    }

    holder.ans3.text = shuffledAnswers[2].answer_text
    holder.ans3.setOnClickListener {
        mCallback.onClick(shuffledAnswers[2],position,it,holder.ans2,holder.ans1)
 }

 interface OnItemClickListener{
      fun onClick(answerSelected: Answer?, questPosition: Int, selectedItemView: View, firstItemView: View, secondItemView: View)
 }

QuizFragment.kt

...

        mAdapter = QuizAdapter(this)
        listQuestions.apply {
            setHasFixedSize(true)
            layoutManager = LinearLayoutManager(activity)
            adapter = mAdapter
            itemAnimator = DefaultItemAnimator()
        }
        mAdapter.setOnItemClickListener(object : QuizAdapter.OnItemClickListener{
            override fun onClick(answerSelected: Answer?,
                                 questPosition: Int,
                                 selectedItemView: View,
                                 firstItemView: View,
                                 secondItemView: View) {
                Snackbar.make(selectedItemView, "Your answer for $questPosition is ${answerSelected!!.isCorrect}.",
                        Snackbar.LENGTH_SHORT)
                        .setAction("Action", null).show()
                selectedItemView.background = ContextCompat.getDrawable(requireContext(),R.drawable.selected_ans_quiz)
                firstItemView.background = ContextCompat.getDrawable(requireContext(),R.drawable.default_ans_quiz)
                secondItemView.background = ContextCompat.getDrawable(requireContext(),R.drawable.default_ans_quiz)
                quizViewModel.chosenAnswers[questPosition] = answerSelected
            }
        })

        fab_endQuiz.setOnClickListener { view ->
            Snackbar.make(view, quizViewModel.chosenAnswers.toString(), Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show()
            //parentFragment?.findNavController()?.navigate(R.id.action_quizFragment_to_nav_home)
        }

如您所见，使用 FAB，我可以测试 selected 答案的正确性，看起来没问题，地图上充满了用户选择，即使 [=50] 有变化=]ion（地图位置，代表问题，修改正确）。但是背景颜色在不同的位置保持混合（当前在 RecyclerView 中可见的颜色加上前面的其他颜色），如前所述。

Answer 1

如果有用的话，我找到了解决办法。我向 Answer class 添加了一个布尔值，以便 RecyclerView 必须检查何时在 xml 中构建其列表，混合我之前所做的 [=16] =]

QuizAdapter.kt

  ...
  
  override fun onBindViewHolder(holder: MyViewHolder, position: Int) {        
 
  ...

    val curQuest = myDataset[position]    
    val shuffledAnswers = curQuest.answers


    holder.ans1.text = shuffledAnswers[0].answer_text
    if(shuffledAnswers[0].isSelected)
        holder.ans1.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.selected_ans_quiz)
    else
        holder.ans1.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
    holder.ans1.setOnClickListener {
        shuffledAnswers[0].isSelected = true
        shuffledAnswers[1].isSelected = false
        shuffledAnswers[2].isSelected = false
        mCallback.onClick(shuffledAnswers[0],position,it,holder.ans2,holder.ans3)
    }

    holder.ans2.text = shuffledAnswers[1].answer_text
    if(shuffledAnswers[1].isSelected)
        holder.ans2.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.selected_ans_quiz)
    else
        holder.ans2.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
    holder.ans2.setOnClickListener {
        shuffledAnswers[0].isSelected = false
        shuffledAnswers[1].isSelected = true
        shuffledAnswers[2].isSelected = false
        mCallback.onClick(shuffledAnswers[1],position,it,holder.ans1,holder.ans3)
    }

    holder.ans3.text = shuffledAnswers[2].answer_text
    if(shuffledAnswers[2].isSelected)
        holder.ans3.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.selected_ans_quiz)
    else
        holder.ans3.background = ContextCompat.getDrawable(parentFragment.requireContext(),R.drawable.default_ans_quiz)
    holder.ans3.setOnClickListener {
        shuffledAnswers[0].isSelected = false
        shuffledAnswers[1].isSelected = false
        shuffledAnswers[2].isSelected = true
        mCallback.onClick(shuffledAnswers[2],position,it,holder.ans1,holder.ans2)
    }
 }

 interface OnItemClickListener{
      fun onClick(answerSelected: Answer?, questPosition: Int, selectedItemView: View, firstItemView: View, secondItemView: View)
 }

QuizFragment.kt

        mAdapter.setOnItemClickListener(object : QuizAdapter.OnItemClickListener{
            override fun onClick(answerSelected: Answer?,
                                 questPosition: Int,
                                 selectedItemView: View,
                                 firstItemView: View,
                                 secondItemView: View) {

                selectedItemView.background = ContextCompat.getDrawable(requireContext(),R.drawable.selected_ans_quiz)
                firstItemView.background = ContextCompat.getDrawable(requireContext(),R.drawable.default_ans_quiz)
                secondItemView.background = ContextCompat.getDrawable(requireContext(),R.drawable.default_ans_quiz)
                quizViewModel.chosenAnswers[questPosition] = answerSelected
            }
        })

在基于测验的应用程序中使用嵌套的 setOnClickListener 的 RecyclerView

RecyclerView with nested setOnClickListener in a quiz based app

android

kotlin

android-recyclerview

onclicklistener

android-viewholder