我正在尝试从JSON获取数据，但它似乎不起作用。永远不会调用OnBindViewHolder ......
适配器代码：
public class AdapterRallye extends RecyclerView.Adapter<AdapterRallye.MyViewHolder> implements View.OnClickListener {
private Context context;
private View.OnClickListener listener;
private List<DataRallye> data;
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView Rallye_Nom;
public ImageView Rallye_Foto;
public TextView Rallye_Provincia;
public TextView Rallye_DataI;
public TextView Rallye_Tipus;
// create constructor to get widget reference
public MyViewHolder(final View itemView) {
super(itemView);
Rallye_Nom = (TextView) itemView.findViewById(R.id.tv_nom);
Rallye_Foto = (ImageView) itemView.findViewById(R.id.iv_foto);
Rallye_Provincia = (TextView) itemView.findViewById(R.id.tv_provincia);
Rallye_DataI = (TextView) itemView.findViewById(R.id.tv_datai);
Rallye_Tipus = (TextView) itemView.findViewById(R.id.tv_tipus);
}
}
// create constructor to innitilize context and data sent from MainActivity
public AdapterRallye(List<DataRallye> dadesrally) {
this.data = dadesrally;
}
// Inflate the layout when viewholder created
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.container_rallye, parent, false);
view.setOnClickListener(this);
return new MyViewHolder(view);
}
// Bind data
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
// Get current position of item in recyclerview to bind data and assign values from list
DataRallye current = data.get(position);
holder.Rallye_Nom.setText(current.getRallyeNom());
holder.Rallye_Tipus.setText(current.getRallyeTipus());
holder.Rallye_DataI.setText(current.getRallyeDataI());
holder.Rallye_Provincia.setText(current.getRallyeProvincia());
holder.Rallye_Provincia.setTextColor(ContextCompat.getColor(context, R.color.colorAccent));
// load image into imageview using glide
Glide.with(context).load("http://rallyecat.esy.es/fotos/" + current.getRallyeFoto())
.placeholder(R.drawable.rallyecatlogo)
.error(R.drawable.rallyecatlogo)
.into(holder.Rallye_Foto);
}
public void setOnClickListener(View.OnClickListener listener) {
this.listener = listener;
}
@Override
public void onClick(View view) {
if (listener != null)
listener.onClick(view);
}
// return total item from List
@Override
public int getItemCount() {
return data.size();
}
}
碎片代码：
public class FragmentRally extends Fragment {
public FragmentRally() {
// Required empty public constructor
}
private List<DataRallye> llistarallyes = new ArrayList<>();
private RecyclerView recyclerView;
private AdapterRallye mAdapter;
private Intent intent;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_fragment_rally, container, false);
recyclerView = (RecyclerView) rootView.findViewById(R.id.llistarallyes);
mAdapter = new AdapterRallye(llistarallyes);
recyclerView.setAdapter(mAdapter);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getContext());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
new AsyncFetch().execute();
mAdapter.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
intent = new Intent(getActivity(), ActivitatDetalls.class);
intent.putExtra("nombarra", llistarallyes.get(recyclerView.getChildAdapterPosition(view)).getRallyeNom());
startActivity(intent);
}
});
return rootView;
}
// CONNECTION_TIMEOUT and READ_TIMEOUT are in milliseconds
public static final int CONNECTION_TIMEOUT = 10000;
public static final int READ_TIMEOUT = 15000;
private class AsyncFetch extends AsyncTask<String, String, String> {
ProgressDialog pdLoading = new ProgressDialog(getActivity());
HttpURLConnection conn;
URL url = null;
@Override
protected void onPreExecute() {
super.onPreExecute();
//this method will be running on UI thread
pdLoading.setMessage("\tCarregant...");
pdLoading.setCancelable(false);
pdLoading.show();
}
@Override
protected String doInBackground(String... params) {
try {
// Enter URL address where your json file resides
// Even you can make call to php file which returns json llistarallyes
url = new URL("http://www.rallyecat.esy.es/Obtenir_events.php");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return e.toString();
}
try {
// Setup HttpURLConnection class to send and receive llistarallyes from php and mysql
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("GET");
// setDoOutput to true as we recieve llistarallyes from json file
//conn.setDoOutput(true);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return e1.toString();
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made
if (response_code == HttpURLConnection.HTTP_OK) {
// Read llistarallyes sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
StringBuilder result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line + "\n");
}
// Pass llistarallyes to onPostExecute method
return (result.toString());
} else {
Toast.makeText(getActivity(), "No hi ha connexió a internet.",
Toast.LENGTH_LONG).show();
return ("No hi ha connexió a internet.");
}
} catch (IOException e) {
e.printStackTrace();
return e.toString();
} finally {
conn.disconnect();
}
}
@Override
protected void onPostExecute(String result) {
//this method will be running on UI thread
pdLoading.dismiss();
try {
JSONArray jArray = new JSONArray(result);
// Extract llistarallyes from json and store into ArrayList as class objects
for (int i = 0; i < jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
DataRallye dadesrallye = new DataRallye();
dadesrallye.setRallyeNom(json_data.getString("nom"));
dadesrallye.setRallyeTipus(json_data.getString("tipus"));
dadesrallye.setRallyeDataI(json_data.getString("datai"));
dadesrallye.setRallyeProvincia(json_data.getString("provincia"));
dadesrallye.setRallyeFoto(json_data.getString("foto"));
llistarallyes.add(dadesrallye);
}
} catch (JSONException e) {
Toast.makeText(getActivity(), e.toString(), Toast.LENGTH_LONG).show();
}
}
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public ViewHolder(LayoutInflater inflater, ViewGroup parent) {
super(inflater.inflate(R.layout.fragment_fragment_rally, parent, false));
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Context context = v.getContext();
Intent intent = new Intent(v.getContext(), ActivitatDetalls.class);
context.startActivity(intent);
}
});
}
}
}
我已经看到问题已经解决的其他StackOverflow帖子，但我一直在尝试很多用户说的解决方案，但没有一个正在运行......
谢谢！
答案 0 :(得分：0)
尝试在onPostExecute（）方法中调用mAdapter.notifyDataSetChanged();。
您需要在进行更改后通知适配器。