Question

我在recyclerView里面制作了一张卡片列表。当卡被保留一段时间后，其数据库中相应的条目将被删除，因此必须删除该卡。可以通过调用设置新的更新适配器来完成。但是我无法在onBindViewHolder中使用setAdapter函数，因为我不知道如何获得相同的recyclelerView。请帮忙。

CODE：

public class RecyclerViewAdapterMain extends RecyclerView.Adapter<RecyclerViewAdapterMain.ViewHolder> {

String[] strings;
DBManager dbManager;

public RecyclerViewAdapterMain(String[] arrayList) {
    this.strings = arrayList;
}

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

@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
    holder.textView.setText(strings[position]);
    holder.cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(holder.itemView.getContext(),SecondActivity.class);
            Bundle bundle = new Bundle();
            bundle.putString("list",strings[position]);
            intent.putExtras(bundle);
            holder.itemView.getContext().startActivity(intent);
            //overridePendingTransition(R.anim.abc_fade_in,R.anim.abc_fade_out);
        }
    });
    holder.cardView.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(final View view) {
            DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    switch (which){
                        case DialogInterface.BUTTON_POSITIVE:
                            dbManager = new DBManager(holder.itemView.getContext(),null,null,1);
                            dbManager.deleteList(strings[position]);
                            String[] strings = dbManager.showLists();
                            RecyclerViewAdapterMain recyclerViewAdapter = new RecyclerViewAdapterMain(strings);
                            //I WANT TO SET UPDATED ADAPTER HERE
                            break;

                        case DialogInterface.BUTTON_NEGATIVE:
                            //No button clicked
                            break;
                    }
                }
            };
            AlertDialog.Builder builder = new AlertDialog.Builder(holder.itemView.getContext());
            builder.setMessage("Are you sure that you want to delete \""+strings[position]+"\"?").setPositiveButton("Yes", dialogClickListener)
                    .setNegativeButton("No", dialogClickListener).show();
            return true;
        }
    });


}

@Override
public int getItemCount() {
    return strings.length;
}

public class ViewHolder extends RecyclerView.ViewHolder{
    CardView cardView;
    TextView textView;
    public ViewHolder(View itemView) {
        super(itemView);
        textView = (TextView) itemView.findViewById(R.id.textView);
        cardView = (CardView) itemView.findViewById(R.id.cardView);
    }
}

}

Answer 1

在onBindViewHolder中的Adapter类中编写

photolist.remove(i);
notifyItemRemoved(i);
notifyItemRangeChanged(i, photolist.size());
notifyDataSetChanged();

Answer 2

您需要更新现有变量

String[] strings;

然后告诉RecyclerView重绘项目。

notifyItemRemoved(position);

或

notifyDataSetChanged();

然后你得到

case DialogInterface.BUTTON_POSITIVE:
                        dbManager = new DBManager(holder.itemView.getContext(),null,null,1);
                        dbManager.deleteList(strings[position]);
                        strings = dbManager.showLists();
                        notifyItemRemoved(position);
                        break;

Answer 3

试试这个

RecyclerViewAdapterMain.this.notifyItemRemoved(position);

如何在其适配器的onBindViewHolder中更新recyclerView？

3 个答案: