使用 RecyclerView 的可扩展 CardView

Expandable CardView using RecyclerView

我正在尝试使用 Recyclerview 制作可扩展的 CardView。我能够看到列表,但是当我点击一些卡片视图并滚动时,其他一些视图也会展开。 就像当我点击位置“0”并滚动然后位置“17”也被展开时..

这是我的代码:

My chapter_cardview.xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">


    <android.support.v7.widget.CardView
        android:id="@+id/cv"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginBottom="4dp"
        android:layout_marginEnd="4dp"
        android:layout_marginLeft="4dp"
        android:layout_marginRight="4dp"
        android:layout_marginStart="4dp"
        android:layout_marginTop="4dp"
        android:theme="@style/Theme.AppCompat.Light.DarkActionBar"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="1.0">

        <android.support.constraint.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <TextView
                android:id="@+id/chapter_detail"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_marginEnd="8dp"
                android:layout_marginLeft="8dp"
                android:layout_marginRight="8dp"
                android:layout_marginStart="8dp"
                android:text="TextView"
                android:visibility="gone"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/chapter_title" />

            <TextView
                android:id="@+id/chapter_title"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_marginBottom="4dp"
                android:layout_marginEnd="8dp"
                android:layout_marginLeft="8dp"
                android:layout_marginRight="8dp"
                android:layout_marginStart="8dp"
                android:layout_marginTop="4dp"
                android:text="TextView"
                app:layout_constraintBottom_toTopOf="@+id/chapter_detail"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent" />
        </android.support.constraint.ConstraintLayout>
    </android.support.v7.widget.CardView>


</android.support.constraint.ConstraintLayout>

My MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    static private List<chapter_title>mDataset;

    // Provide a reference to the views for each data item
    // Complex data items may need more than one view per item, and
    // you provide access to all the views for a data item in a view holder
    public static class ViewHolder extends RecyclerView.ViewHolder {
        // each data item is just a string in this case
        public CardView mCardView;
        private TextView mchapter_tile;
        private TextView mchapter_detail;
        public ViewHolder(View itemview) {
            super(itemview);

            mCardView = itemView.findViewById(R.id.cv);
            mchapter_tile = itemview.findViewById(R.id.chapter_title);
            mchapter_detail = itemview.findViewById(R.id.chapter_detail);
        }
    }

    // Provide a suitable constructor (depends on the kind of dataset)
    public MyAdapter(List<chapter_title> myDataset) {
        mDataset = myDataset;
    }

    // Create new views (invoked by the layout manager)
    @Override
    public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                                   int viewType) {
        // create a new view
        ViewHolder vh = null;
        View view = (View) LayoutInflater.from(parent.getContext())
                .inflate(R.layout.chapter_cardview, parent, false);
        vh = new ViewHolder(view);

        Log.e("viewType: ", ""+viewType);
        if (viewType == 1)
            vh.mchapter_detail.setVisibility(View.VISIBLE);
        else
            vh.mchapter_detail.setVisibility(View.GONE);

        return vh;
    }


    // Replace the contents of a view (invoked by the layout manager)
    @Override
    public void onBindViewHolder(ViewHolder holder, final int position) {
        // - get element from your dataset at this position
        // - replace the contents of the view with that element
        holder.mchapter_tile.setText(mDataset.get(position).title);
        holder.mCardView.setTag(position);

        holder.mCardView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int position = (Integer)v.getTag();
                boolean isShown = MyAdapter.mDataset.get(position).isExpanded;
                Log.e("Clicked on:", ""+ position);

                if(isShown)
                {
                    MyAdapter.mDataset.get(position).isExpanded = false;
                    ((CardView)v).findViewById(R.id.chapter_detail).setVisibility(View.GONE);
                }
                else
                {
                    ((CardView)v).findViewById(R.id.chapter_detail).setVisibility(View.VISIBLE);
                    MyAdapter.mDataset.get(position).isExpanded = true;
                }



            }
        });


    }

    @Override
    public int getItemViewType(int position)
    {

      //  Log.e("getItemType, position", position+"");
        if(mDataset.get(position).isExpanded==true)
            return 1;
        else
            return 0;
    }

    // Return the size of your dataset (invoked by the layout manager)
    @Override
    public int getItemCount() {
  //      Log.e("list size", mDataset.size()+"");
        return mDataset.size()-50;

    }
}



`

适配器文件中有一些更改。在绑定视图时,我们首先根据我们设置视图可见性的结果检查 isExpanded。下面是适配器的代码。

public class MyAdapter 扩展 RecyclerView.Adapter { 私有列表 mDataset;

    // Provide a reference to the views for each data item
    // Complex data items may need more than one view per item, and
    // you provide access to all the views for a data item in a view holder
    public static class ViewHolder extends RecyclerView.ViewHolder {
        // each data item is just a string in this case
        public CardView mCardView;
        private TextView mchapter_tile;
        private TextView mchapter_detail;
        public ViewHolder(View itemview) {
            super(itemview);

            mCardView = itemView.findViewById(R.id.cv);
            mchapter_tile = itemview.findViewById(R.id.chapter_title);
            mchapter_detail = itemview.findViewById(R.id.chapter_detail);
        }
    }

    // Provide a suitable constructor (depends on the kind of dataset)
    public MyAdapter(List<chapter_title> myDataset) {
        mDataset = myDataset;
    }

    // Create new views (invoked by the layout manager)
    @Override
    public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                                   int viewType) {
        // create a new view
        ViewHolder vh = null;
        View view = (View) LayoutInflater.from(parent.getContext())
                .inflate(R.layout.stack_question_2, parent, false);
        vh = new ViewHolder(view);
        return vh;
    }


    // Replace the contents of a view (invoked by the layout manager)
    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) {
        // - get element from your dataset at this position
        // - replace the contents of the view with that element
        final chapter_title chapter_title = mDataset.get(position);
        holder.mchapter_tile.setText(chapter_title.title);
        holder.mCardView.setTag(position);

        if (chapter_title.isExpanded)
            holder.mchapter_detail.setVisibility(View.VISIBLE);
        else
            holder.mchapter_detail.setVisibility(View.GONE);

        holder.mCardView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {


                if(mDataset.get(position).isExpanded)
                {
                    mDataset.get(position).isExpanded = false;
                    ((CardView)v).findViewById(R.id.chapter_detail).setVisibility(View.GONE);
                }
                else
                {
                    ((CardView)v).findViewById(R.id.chapter_detail).setVisibility(View.VISIBLE);
                    mDataset.get(position).isExpanded = true;
                }
                //notifyDataSetChanged();
                notifyItemChanged(position);
            }
        });


    }

    @Override
    public int getItemViewType(int position)
    {
        //  Log.e("getItemType, position", position+"");
        if(mDataset.get(position).isExpanded==true)
            return 1;
        else
            return 0;
    }

    // Return the size of your dataset (invoked by the layout manager)
    @Override
    public int getItemCount() {
        //      Log.e("list size", mDataset.size()+"");
        return mDataset.size();
    }
}

希望对您有所帮助。