【发布时间】：2021-07-13 10:56:22
【问题描述】：
我有一个问题，响应调用中的 notifyDataSetChanged() 将清除 recyclerview，但如果使用 onClick 手动启动适配器，则 recyclerview 可以工作。在调用 notifyDataSetChanged() 之前，我已经测试了 List 里面有项目，所以我不确定这里有什么问题。
[Main Activity] 这可行，但我必须手动单击 bnQuery。
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
apiInterface = API_client.getClient().create(APIInterface.class);
etCoin = (EditText) findViewById(R.id.etCoin);
bnQuery = (Button) findViewById(R.id.bnQuery);
rcvMain = findViewById(R.id.rcvMain);
getCoinData("2");
//initRCV_Main();
bnQuery.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//getCoinData("2");
initRCV_Main();
}
});
}
private void initRCV_Main() {
rcvMainAdp = new rcvMainAdapter(cList);
rcvMain.setAdapter(rcvMainAdp);
rcvMain.setLayoutManager(new LinearLayoutManager(this));
}
private void getCoinData(String coinLimit){
Call<cInfoPack> call = apiInterface.doGetCoinData(coinLimit);
call.enqueue(new Callback<cInfoPack>() {
@Override
public void onResponse(Call<cInfoPack> call, Response<cInfoPack> response) {
cInfoPack list = response.body();
List<cData> listSorter = new ArrayList<>();
listSorter.addAll(list.getData());
Collections.sort(listSorter, new SortbyVolChg());
cList.clear();
cList = listSorter;
System.out.println("list " + list.getData().get(0).getQuote());
System.out.println("listSorter " + listSorter.get(0).getQuote());
System.out.println("cList " + cList.get(0).getQuote());
//rcvMainAdp.notifyDataSetChanged();
}
@Override
public void onFailure(Call<cInfoPack> call, Throwable t) {
Toast.makeText(MainActivity.this, "onFailure", Toast.LENGTH_SHORT).show();
Log.d("XXXX", t.getLocalizedMessage());
call.cancel();
}
});
}
[主要活动] 如果我在 onCreate 期间启动 recyclerview 并在 getCoinData 期间使用 notifyDataSetChanged()，我会得到一个空白的 recycleview。 system.out 显示列表中都包含信息。
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
apiInterface = API_client.getClient().create(APIInterface.class);
etCoin = (EditText) findViewById(R.id.etCoin);
bnQuery = (Button) findViewById(R.id.bnQuery);
rcvMain = findViewById(R.id.rcvMain);
getCoinData("2");
initRCV_Main();
bnQuery.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//getCoinData("2");
//initRCV_Main();
}
});
}
private void initRCV_Main() {
rcvMainAdp = new rcvMainAdapter(cList);
rcvMain.setAdapter(rcvMainAdp);
rcvMain.setLayoutManager(new LinearLayoutManager(this));
}
private void getCoinData(String coinLimit){
Call<cInfoPack> call = apiInterface.doGetCoinData(coinLimit);
call.enqueue(new Callback<cInfoPack>() {
@Override
public void onResponse(Call<cInfoPack> call, Response<cInfoPack> response) {
cInfoPack list = response.body();
List<cData> listSorter = new ArrayList<>();
listSorter.addAll(list.getData());
Collections.sort(listSorter, new SortbyVolChg());
cList.clear();
cList = listSorter;
System.out.println("list " + list.getData().get(0).getQuote());
System.out.println("listSorter " + listSorter.get(0).getQuote());
System.out.println("cList " + cList.get(0).getQuote());
rcvMainAdp.notifyDataSetChanged();
}
@Override
public void onFailure(Call<cInfoPack> call, Throwable t) {
Toast.makeText(MainActivity.this, "onFailure", Toast.LENGTH_SHORT).show();
Log.d("XXXX", t.getLocalizedMessage());
call.cancel();
}
});
}
[适配器]
public class rcvMainAdapter extends RecyclerView.Adapter<rcvMainAdapter.ViewHolder> {
private List<cData> idxCoin;
//ItemClickListener itemClickListener;
rcvMainAdapter(List<cData> data) {this.idxCoin = data;}
@NonNull
@NotNull
@Override
public ViewHolder onCreateViewHolder(@NonNull @NotNull ViewGroup parent, int viewType) {
Context context = parent.getContext();
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.rcv_main,parent, false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}
@Override
public void onBindViewHolder(@NonNull @NotNull ViewHolder holder, int position) {
cData cdata = idxCoin.get(position);
TextView tvSym = holder.tvSymbol;
tvSym.setText(cdata.getSymbol());
TextView tvQuo = holder.tvQuote;
BigDecimal tvQuote_BD = new BigDecimal(cdata.getQuote().getuSD().getPrice().toString());
tvQuote_BD.setScale(6, RoundingMode.DOWN);
tvQuo.setText(tvQuote_BD.toString());
TextView tvV24 = holder.tvVolume24;
BigDecimal tvVolume24_BD = new BigDecimal(cdata.getQuote().getuSD().getVolume24h().toString());
BigInteger tvVolume24_BI = tvVolume24_BD.toBigInteger();
tvV24.setText(tvVolume24_BI.toString());
}
@Override
public int getItemCount() {
return idxCoin.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
TextView tvSymbol, tvQuote, tvVolume24;
public ViewHolder(@NonNull @NotNull View itemView) {
super(itemView);
tvSymbol = itemView.findViewById(R.id.tvSymbol);
tvQuote = itemView.findViewById(R.id.tvQuote);
tvVolume24 = itemView.findViewById(R.id.tvVolume24);
//itemView.setOnClickListener(this);
}
}
/*
public interface ItemClickListener{
void onItemClick(View view, int position);
}
*/
}
PS：对于垃圾编码表示歉意，因为这是自学并修改了网上找到的一些代码。
【问题讨论】：
-
你的变量名真的很混乱，希望它们对你更有意义，以后没有其他人需要查看这段代码:) 不知道为什么东西以
c为前缀。据我所知，我看不到您如何更改适配器的内容。你没有像adapter.items = foo这样的东西，然后是通知声明
标签： java android android-recyclerview