android recyclerview分组怎么实现

要实现Android RecyclerView的分组功能，可以按照以下步骤进行：

1. 创建一个包含分组数据和子项数据的数据结构。可以使用一个包含分组名称和子项列表的对象来表示每个分组。例如：

public class GroupData { private String groupName; private List<ItemData> itemList; // getter and setter methods } public class ItemData { private String itemName; // getter and setter methods } 

2. 创建一个RecyclerView的Adapter类，继承自RecyclerView.Adapter。在Adapter类中，需要创建两个ViewHolder类，一个用于显示分组，另一个用于显示子项。例如：

public class GroupViewHolder extends RecyclerView.ViewHolder { private TextView groupNameTextView; public GroupViewHolder(View itemView) { super(itemView); groupNameTextView = itemView.findViewById(R.id.group_name_textview); } public void bind(GroupData groupData) { groupNameTextView.setText(groupData.getGroupName()); } } public class ItemViewHolder extends RecyclerView.ViewHolder { private TextView itemNameTextView; public ItemViewHolder(View itemView) { super(itemView); itemNameTextView = itemView.findViewById(R.id.item_name_textview); } public void bind(ItemData itemData) { itemNameTextView.setText(itemData.getItemName()); } } public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { private List<GroupData> groupList; // constructor and other methods @Override public int getItemCount() { return groupList.size(); } @Override public int getItemViewType(int position) { if (position < 0 || position >= groupList.size()) { return -1; } return groupList.get(position).getItemList().isEmpty() ? 0 : 1; } @NonNull @Override public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) { LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext()); if (viewType == 0) { View view = layoutInflater.inflate(R.layout.group_layout, parent, false); return new GroupViewHolder(view); } else { View view = layoutInflater.inflate(R.layout.item_layout, parent, false); return new ItemViewHolder(view); } } @Override public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) { if (holder instanceof GroupViewHolder) { ((GroupViewHolder) holder).bind(groupList.get(position)); } else if (holder instanceof ItemViewHolder) { ((ItemViewHolder) holder).bind(groupList.get(position).getItemList().get(0)); } } } 

3. 在Activity或Fragment中，创建RecyclerView并设置Adapter。例如：

RecyclerView recyclerView = findViewById(R.id.recycler_view); recyclerView.setLayoutManager(new LinearLayoutManager(this)); MyAdapter myAdapter = new MyAdapter(groupList); recyclerView.setAdapter(myAdapter); 

这样就可以实现RecyclerView的分组功能了。