我正在开发应用程序时遇到一些问题，我的问题是，如果第一次打开recycleview来获取数据显示完全正确，则意味着第一次没有问题就正确显示数据，但是应用程序再次关闭，请重新打开recyclerview来不显示数据。我在工作改造库上使用mysql数据库thanx前进。
RecyclerView recyclerView;
EditText searchcard;
Superdent_Invi_fetct.Adapter adapter;
FloatingActionButton rotationbtn;
List<Supert_Invigilator_Model> data;
String supert_id, hall_id;
LinearLayoutManager layoutManager;
SharedPreferences sharedPreferences;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_superdent__invi_fetct);
supert_id = getIntent().getStringExtra("id");
hall_id = getIntent().getStringExtra("hall_id");
rotationbtn = findViewById(R.id.rotat_float_btn);
searchcard = (EditText) findViewById(R.id.searchcard);
recyclerView = (RecyclerView) findViewById(R.id.std_report_list);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
searchcard.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
Log.e("onTextChanged: ", s.toString());
if (adapter != null) {
if (!s.toString().isEmpty()) {
Filter filter = adapter.getFilter();
filter.filter(s.toString());
adapter.notifyDataSetChanged();
}
} else {
searchcard.setError("List is Empty");
}
}
@Override
public void afterTextChanged(Editable s) {
Filter filter = adapter.getFilter();
filter.filter(s.toString());
}
});
rotationbtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
screenscape();
}
});
ShowReport();
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
switch (requestCode) {
case 555:
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Permission Granted
// createShopingPdf();
} else {
// Permission Denied
Toast.makeText(this, "WRITE_EXTERNAL Permission Denied", Toast.LENGTH_SHORT)
.show();
}
break;
default:
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
public void ShowReport() {
HashMap<String, String> map = new HashMap<>();
map.put("id", supert_id);
map.put("hall_id", hall_id);
Invi_std_Api apiInterface = ApiClient.getClient().create(Invi_std_Api.class);
Call<List<Supert_Invigilator_Model>> call = apiInterface.getsuperdentinvigilator(map);
call.enqueue(new Callback<List<Supert_Invigilator_Model>>() {
@Override
public void onResponse(Call<List<Supert_Invigilator_Model>> call, Response<List<Supert_Invigilator_Model>> response) {
data = response.body();
Log.e("size", "onResponse: " + data.size());
adapter = new Superdent_Invi_fetct.Adapter(Superdent_Invi_fetct.this, data);
recyclerView.setAdapter(adapter);
}
@Override
public void onFailure(Call<List<Supert_Invigilator_Model>> call, Throwable t) {
Log.e("Exception", "onFailure: " + t.getMessage());
}
});
}
public void screenscape() {
int orientation = getResources().getConfiguration().orientation;
switch (orientation) {
case Configuration.ORIENTATION_LANDSCAPE:
runOnUiThread(new Runnable() {
@Override
public void run() {
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
});
break;
case Configuration.ORIENTATION_PORTRAIT:
runOnUiThread(new Runnable() {
@Override
public void run() {
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
}
});
break;
}
}
public class Adapter extends RecyclerView.Adapter<Superdent_Invi_fetct.Adapter.MyViewHolder> implements Filterable {
Context context;
List<Supert_Invigilator_Model> data;
List<Supert_Invigilator_Model> copyList;
public Adapter(Context context, List<Supert_Invigilator_Model> data) {
this.context = context;
this.data = data;
this.copyList = data;
}
@NonNull
@Override
public Superdent_Invi_fetct.Adapter.MyViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.invigilator_record_spt, viewGroup, false);
return new Superdent_Invi_fetct.Adapter.MyViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull Superdent_Invi_fetct.Adapter.MyViewHolder holder, int i) {
final Supert_Invigilator_Model model = data.get(i);
// holder.tvid.setText(copyList.get(i).getInvigId());
holder.tvinvname.setText(copyList.get(i).getName());
holder.tvhall.setText(copyList.get(i).getTitle());
holder.tvroleid.setText(copyList.get(i).getRoleId());
holder.tvhallid.setText(copyList.get(i).getHallId());
}
@Override
public int getItemCount() {
return copyList.size();
}
@Override
public Filter getFilter() {
Filter filter = new Filter() {
@SuppressWarnings("unchecked")
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
copyList = (List<Supert_Invigilator_Model>) results.values;
notifyDataSetChanged();
}
@Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults results = new FilterResults();
List<Supert_Invigilator_Model> FilteredArrList = new ArrayList<>();
if (data == null) {
data = new ArrayList<>();
}
if (constraint == null || constraint.length() == 0) {
results.count = data.size();
results.values = data;
} else {
constraint = constraint.toString().toLowerCase();
for (int i = 0; i < data.size(); i++) {
String item = data.get(i).getName();
if (item.toLowerCase().contains(constraint.toString())) {
FilteredArrList.add(new Supert_Invigilator_Model(
data.get(i).getCnic(),
data.get(i).getDeptId(),
data.get(i).getFName(),
data.get(i).getHallId(),
data.get(i).getId(),
data.get(i).getInvigId(),
data.get(i).getName(),
data.get(i).getPassword(),
data.get(i).getRoleId(),
data.get(i).getRoll(),
data.get(i).getSupertId(),
data.get(i).getTitle(),
data.get(i).getUserId()));
}
}
results.count = FilteredArrList.size();
results.values = FilteredArrList;
}
return results;
}
};
return filter;
}
public class MyViewHolder extends RecyclerView.ViewHolder {
TextView tvid, tvinvname, tvhall, tvroleid, tvhallid;
public MyViewHolder(@NonNull View itemView) {
super(itemView);
// tvid = itemView.findViewById(R.id.tID);
tvinvname = itemView.findViewById(R.id.tIviglatorName);
tvhall = itemView.findViewById(R.id.tHallName);
tvroleid = itemView.findViewById(R.id.troleid);
tvhallid = itemView.findViewById(R.id.thallid);
}
public List<Supert_Invigilator_Model> getList() {
Log.e("getList: ", "" + copyList);
return copyList;
}
}
}
}
设置适配器后，尝试以adapter.notifyDataSetChanged();方法调用ShowReport。
此外，请勿尝试在ShowReport方法中设置适配器。尝试使用另一个列表在onCreate中进行设置，然后只需在ShowReport方法中将该响应添加到该列表中即可。
而且，请尝试调试代码，以便您知道为什么第二次运行中不显示数据。