android - RecyclerView Viewholder 重用

Question

我正在创建一个 RecyclerView，它会在用户触摸它时自行展开，并在用户再次触摸它时自行关闭。下面是我的代码:

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.RecViewHolder> {
    ArrayList<String> values;
    ArrayList<Integer> expandedPosition;
    public static class RecViewHolder extends RecyclerView.ViewHolder {
        ...
        private boolean resultsOpened = false;
        ...
        RelativeLayout favHeaderLayout;
        RelativeLayout favResultsLayout;

        public RecViewHolder (View itemView) {
            super(itemView);
            favHeaderLayout.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if (!resultsOpened) {
                        expandLayout();
                    } else {
                        favResultsLayout.setVisibility(View.GONE);
                        resultsOpened = false;
                    }
                }
            });

        }

        public void expandLayout() {
            favResultsLayout.setVisibility(View.VISIBLE);
            resultsOpened = true;
            //I populate my expanded layout here
        }
    }

    public RecyclerViewAdapter (Context context, ArrayList<String> values) {
        this.context = context;
        this.values= values;
    }

    @Override
    public RecViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_file, parent, false);
        RecViewHolder recViewHolder= new RecViewHolder(v);
        return recViewHolder;
    }

    @Override
    public void onBindViewHolder(RecViewHolder recViewHolder , int position) {
    }

    @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
    }

    @Override
    public int getItemCount() {
        return values.size();
    }

}

当我触摸第一个 View 时，它应该会自行展开。但是，当适配器有更多数据并且我触摸第一个 View 时，该 View 会展开，并且 RecyclerView 底部的另一个 View (例如第 8 个 View )也会展开。我如何确保只有被触摸的 View 展开而另一个保持关闭？

编辑

我已经尝试将展开的 View 位置存储在数组列表和 onBindViewHolder 中，检查哪些 View 已展开并仅展开它们:

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.RecViewHolder> {
    ArrayList<String> values;
    ArrayList<Integer> expandedPosition;
    public static class RecViewHolder extends RecyclerView.ViewHolder {
        ...
        private boolean resultsOpened = false;
        ...
        RelativeLayout favHeaderLayout;
        RelativeLayout favResultsLayout;

        public RecViewHolder (View itemView) {
            super(itemView);


        }

    }

    public RecyclerViewAdapter (Context context, ArrayList<String> values) {
        this.context = context;
        this.values= values;
    }

    @Override
    public RecViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_file, parent, false);
        RecViewHolder recViewHolder= new RecViewHolder(v);
        return recViewHolder;
    }

    @Override
    public void onBindViewHolder(RecViewHolder recViewHolder , int position) {
        recViewHolder.favResultsLayout.setVisibility(View.GONE);
        for(int i= 0; i < expandedPosition.size(); i ++){
            recViewHolder.favResultsLayout.setVisibility(View.VISIBLE);
        }
        recViewHolder.favHeaderLayout.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                     if (!expandedPosition.contains(position)) {
                        expandLayout(recViewHolder);
                        expandedPosition.add(position);
                    } else {
                        recViewHolder.favResultsLayout.setVisibility(View.GONE);
                        for(int i = 0; i < expandedPosition.size(); i ++){
                            if (expandedPosition.get(i) == position){
                                    expandedPosition.remove(i);
                            }
                        }
                    }
                }
            });
    }
    public void expandLayout() {
            favResultsLayout.setVisibility(View.VISIBLE);
            //I populate my expanded layout here
        }
    @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
    }

    @Override
    public int getItemCount() {
        return values.size();
    }

}

仍然没有运气:(

Answer 1

正如类(class)名称所说，这一切都是关于回收...

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.RecViewHolder> {
    ArrayList<String> values;
    SparseBooleanArray expanded = new SparseBooleanArray();
    public static class RecViewHolder extends RecyclerView.ViewHolder {
        //EDIT!!!!!
        public RecViewHolder (View itemView, final RecyclerViewAdapter adapter) {
        //rest of the code ...
        favHeaderLayout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) { 
                final int currentPosition = getAdapterPosition();
                //is a view at current position expanded?
                if(adapter.expanded.get(currentPosition ))
                    //if so it shouldn't be
                    adapter.expanded.delete(getAdapterPosition(currentPosition));
                else
                    //if not, expand
                    adapter.expanded.put(currentPosition, true);
                //wheeee inform the adapter to rebind
                adapter.notifyItemChanged(currentPosition);
                //setupExpanded(expanded.get(currentPosition)); 
            }
        });
        }
        protected void setupExpanded(boolean state) {
        //ONLY hide show layouts based on state
        }
    }
    @Override
    public RecViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_file, parent, false);
        RecViewHolder recViewHolder= new RecViewHolder(v, this);
        return recViewHolder;
    }

    @Override
    public void onBindViewHolder(RecViewHolder recViewHolder , int position)    {
        //this line should be self explanatory
        recViewHolder.setupExpanded(expanded.get(position));
    }

    //rest of the code
}