Question

所以我有这两个arraylists：

ArrayList<String> a = new ArrayList();
ArrayList<String> b = new ArrayList();

a.add("bear","lion","bird","goose","cat");
b.add("car","bike");

然后我将它们添加到一个新的arraylist：

ArrayList<ArrayList<String>> list = new ArrayList();

list.add(a);
list.add(b);

然后，我将此arraylist设置为customlerview的自定义适配器。在这个适配器中，我还将这两个arraylists（在最后一个arraylist中）设置为recyclerview，它是适配器的项目视图。因此，它是另一个recyclerview的自定义适配器内的recyclerview。

然而，当我调试应用程序时，第一个包含5个项目的arraylist在recyclerview上只显示2个。像第二个arraylist。然后，当我删除第二个arraylist并再次调试应用程序时，第一个arraylist将显示其真实值。

如果我在recyclerview显示错误值后调用notifyDataSetChanged（），它将显示其真值。所以，我认为是因为某些视图（我不知道如果它是recyclelerview，片段或其他东西）还没有正确加载。

我该如何解决这个问题？谢谢。

修改这是我的适配器代码：

 public class MyAdapter extends RecyclerView.Adapter<AdapterNearMe.MyViewHolder> {

    private Context context;
    private List<List<String>> list;

    public class MyViewHolder extends RecyclerView.ViewHolder {
         public RecyclerView rView;

         public MyViewHolder(View view) {
              super(view);
              rView = (RecyclerView) view.findViewById(R.id.rview);
         }
     }

     public MyAdapter (Context context, List<List<String>> list) {
         this.context= context;
         this.list = list;
     }

     @Override
     public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
         View itemView = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.item_near_me, parent, false);

         return new MyViewHolder(itemView);
     }

     @Override
     public void onBindViewHolder(final MyViewHolder holder, final int position) {
        final List<String> newList= list.get(position);

        holder.rView.setAdapter(new AdapterRView(context,newList));
        holder.rView.setLayoutManager(new GridLayoutManager(context,3));
     }

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

Answer 1

RecyclerView's bindViewHolder为您提供了在单元格view上设置属性的功能，而不是为父adapter设置RecylerView。

@Override
public void onBindViewHolder(final MyViewHolder holder, final int position) {

// This should single Model rather than List
final List<Model> newList= list.get(position);

// Instead of creating another recyclerview, check how to create section view
holder.rView.setAdapter(new AdapterRView(context,newList));
holder.rView.setLayoutManager(new GridLayoutManager(context,3));
}

Answer 2

如何在onCreateViewHolder（）方法中设置适用于recyclerview的适配器（带空arraylist）？然后用真实数据填充它，然后在onBindViewHolder（）中调用notifyDataSetChange（）？

public class MyAdapter extends RecyclerView.Adapter<AdapterNearMe.MyViewHolder> {

private Context context;
private List<List<String>> list;

public class MyViewHolder extends RecyclerView.ViewHolder {
     public RecyclerView rView;

     public MyViewHolder(View view) {
          super(view);
          rView = (RecyclerView) view.findViewById(R.id.rview);
          rView.setLayoutManager(new GridLayoutManager(context,3));
     }
 }

 public MyAdapter (Context context, List<List<String>> list) {
     this.context= context;
     this.list = list;
 }

 @Override
 public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
     View itemView = LayoutInflater.from(parent.getContext())
        .inflate(R.layout.item_near_me, parent, false);

     MyViewHolder holder = new MyViewHolder(itemView);
     holder.rView.setAdapter(new AdapterRView(context, new ArrayList<String>));

     return holder;

 }

 @Override
 public void onBindViewHolder(final MyViewHolder holder, final int position) {
    final List<String> newList = list.get(position);

    AdapterRView adapter = holder.rView.getAdapter();
    if (adapter != null) {
        adapter.swapList(newList);
        adapter.notifyDataSetChanged();
    }
 }

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

您需要添加一个额外的方法来交换AdapterRView.class的列表：

public class AdapterRView.class {

....

private List<String> list;

    public void swapList(List<String> list) {
        this.list = list;
    }
}

在另一个recyclerview

2 个答案: