Recycleview复选框状态不断变化

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    private List<Item> itemList;

    public MyAdapter(List<Item> itemList) {
        this.itemList = itemList;
    }

    public class ViewHolder extends RecyclerView.ViewHolder {
        public CheckBox checkBox;

        public ViewHolder(View itemView) {
            super(itemView);
            checkBox = itemView.findViewById(R.id.checkbox);
        }
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_layout, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, final int position) {
        final Item item = itemList.get(position);
        holder.checkBox.setChecked(item.isSelected());

        holder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                item.setSelected(isChecked);
            }
        });
    }

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

    public List<Item> getSelectedItems() {
        List<Item> selectedItems = new ArrayList<>();
        for (Item item : itemList) {
            if (item.isSelected()) {
                selectedItems.add(item);
            }
        }
        return selectedItems;
    }
}

public class Item {
    private boolean isSelected;
    // other item data

    public boolean isSelected() {
        return isSelected;
    }

    public void setSelected(boolean selected) {
        isSelected = selected;
    }
}