I am fetching data from movie database API and sometimes images do not load and sometimes it loads slowly. I am decoding images url to bitmap and then setting them to image view using adapter.Please tell where i am making mistake.I am getting images url right from API.
MainActivity.java:
package com.example.sahilshokeen.movie;
public class MainActivity extends Activity {
private RecyclerView recyclerView;
private GridLayoutManager manager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//checking network
ConnectivityManager connMgr = (ConnectivityManager)
getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
if (networkInfo != null && networkInfo.isConnected()) {
// fetch data
new FetchData().execute();
new Convert().execute();
} else {
// display error
Toast toast = Toast.makeText(this, "No Network", Toast.LENGTH_LONG);
toast.show();
}
//setting adapter
recyclerView = (RecyclerView) findViewById(R.id.recyclers);
manager = new GridLayoutManager(MainActivity.this, 2);
recyclerView.setAdapter(new Adapter());
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(manager);
}
public class FetchData extends AsyncTask<Void, Void, Void> {
private HttpURLConnection connection = null;
private BufferedReader reader = null;
private String json;
private String urlString = "http://api.themoviedb.org/3/movie/popular?api_key=b6f6fcfbb225d8c500e4404655ccadcc&certification=G";
private String image = " http://image.tmdb.org/t/p/w92/";
#Override
protected Void doInBackground(Void... params) {
//connecting to network
try {
URL url = new URL(urlString);
connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.connect();
StringBuffer buffer = new StringBuffer();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
String line;
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
json = buffer.toString();
//getting json data
try {
JSONObject object = new JSONObject(json);
JSONArray array = object.getJSONArray("results");
for (int i = 0; i < 6; i++) {
Data.objects[i] = array.getJSONObject(i);
Data.title[i] = Data.objects[i].getString("original_title");
Data.overview[i] = Data.objects[i].getString("overview");
Data.date[i] = Data.objects[i].getString("release_date");
Data.image[i] = Data.objects[i].getString("poster_path");
Data.vote[i] = Data.objects[i].getDouble("vote_average");
Data.image[i] = image + Data.image[i];
}
} catch (JSONException e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
public class Convert extends AsyncTask<Void, Void, Void>{
#Override
protected Void doInBackground(Void... params) {
for(int i=0;i<6;i++) {
try {
URL url = new URL(Data.image[i]);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
Data.bImage[i] = myBitmap;
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
if (id == R.id.action_refresh) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Adapter.java:
package com.example.sahilshokeen.movie;
public class Adapter extends RecyclerView.Adapter<Adapter.Holder> {
public static class Holder extends RecyclerView.ViewHolder {
public CardView cardView;
public ImageView imageView;
public Holder(View itemView) {
super(itemView);
cardView = (CardView) itemView.findViewById(R.id.card);
imageView = (ImageView) itemView.findViewById(R.id.images);
}
}
#Override
public Holder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.grid_item, parent, false);
Holder holder = new Holder(view);
return holder;
}
#Override
public void onBindViewHolder(Holder holder, int position) {
holder.imageView.setImageBitmap(Data.bImage[position]);
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
#Override
public int getItemCount() {
return Data.bImage.length;
}
}
Data.java:
package com.example.sahilshokeen.movie;
public class Data {
public static JSONObject[] objects = new JSONObject[6];
public static String[] title = new String[6];
public static String[] overview = new String[6];
public static String[] date = new String[6];
public static String[] image = new String[6];
public static Bitmap[] bImage = new Bitmap[6];
public static Double[] vote = new Double[6];
}
You are using InputStreamReader, which i think isn't necessary, It may as well be the reason why it is slow. I can't post this as a comment so I have to post as answer.
Try this code for doInBackground instead of using InputStreamReader.
//Call your method
new FetchData().execute("http://api.themoviedb.org/3/movie/popular?api_key=b6f6fcfbb225d8c500e4404655ccadcc&certification=G");
public class FetchData extends AsyncTask<String, Void, Void> {
#Override
protected Boolean doInBackground(String... urls) {
try {
HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 5000);
HttpConnectionParams.setSoTimeout(httpParameters, 5000);
//------------------>>
HttpGet httppost = new HttpGet(urls[0]);
HttpClient httpclient = new DefaultHttpClient(httpParameters);
HttpResponse response = httpclient.execute(httppost);
// StatusLine stat = response.getStatusLine();
int status = response.getStatusLine().getStatusCode();
if (status == 200) {
HttpEntity entity = response.getEntity();
String data = EntityUtils.toString(entity);
JSONObject jsono = new JSONObject(data);
JSONArray jarray = jsono.getJSONArray("results");
for (int i = 0; i < jarray.length(); i++) {
JSONObject object = jarray.getJSONObject(i);
//Get your data here Example : poster_path
object.getString("poster_path");
}
return true;
}
//------------------>>
} catch (ConnectTimeoutException e) {
Log.e("Timeout Exception: ", e.toString());
} catch (SocketTimeoutException ste) {
Log.e("Timeout Exception: ", ste.toString());
} catch (ParseException e1) {
e1.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
return false;
}
}
And you need to import this classes
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.net.SocketTimeoutException;
import java.util.ArrayList;
Use Library Such as Glide Or Picasso.!
#Override
public void onBindViewHolder(Holder holder, int position) {
// holder.imageView.setImageBitmap(Data.bImage[position]);
Glide.with(ctx)
.load(imageDownloadUrl)
.into(holder.imageView);
Picasso.with(context).load("").placeholder(Data.bImage[position]).into(holder.imageView);
or
//R.drawable.drawableName
Picasso.with(context).load(Data.bImage[position]).into(holder.imageView);
}
compile 'com.squareup.picasso:picasso:2.5.2'
compile 'com.github.bumptech.glide:glide:3.6.1'
compile 'com.android.support:support-v4:25.1.0'
Related
RecyclerView is updated after the search and mCallback returns null but before search works correctly.
AdapterHistorico.java
package com.beliasdev.cadjobel.adapter;
import android.content.Context;
import android.content.DialogInterface;
import android.support.v7.app.AlertDialog;
import android.support.v7.widget.RecyclerView;
import android.text.TextUtils;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import com.beliasdev.cadjobel.R;
import com.beliasdev.cadjobel.utility.DrawableHelper;
import com.bumptech.glide.Glide;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
public class AdapterHistorico extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private Spinner spinner1;
private String dateold;
private String datenew;
private String compareValue;
private String concluido;
private String em_andamento;
private String cancelado;
private String concluido1;
private String em_andamento1;
private String cancelado1;
private String status;
private Context context;
private LayoutInflater inflater;
private IProcessFilter mCallback;
private ArrayList<DataHistorico> data;
//List<DataHistorico> data= Collections.emptyList();
DataHistorico current;
int currentPos=0;
public AdapterHistorico(Context context, ArrayList<DataHistorico> data, IProcessFilter callback){
this.context=context;
inflater= LayoutInflater.from(context);
this.data=data;
mCallback = callback;
}
public interface IProcessFilter {
void onProcessFilter(DataHistorico produtos);
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view=inflater.inflate(R.layout.container_historico, parent,false);
MyHolder holder=new MyHolder(view);
return holder;
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
final DataHistorico pedidos = data.get(position);
values from list
MyHolder myHolder= (MyHolder) holder;
final DataHistorico current = data.get(position);
dateold = current.pData;
try {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat df2 = new SimpleDateFormat("dd/MM/yyyy 'ás' HH:mm:ss");
datenew = df2.format(format.parse(dateold));
} catch (ParseException e) {
e.printStackTrace();
}
myHolder.txtPedidoNumero.setText("N° " + current.pNumero);
myHolder.txtPedidoCliente.setText(current.pCliente);
myHolder.txtPedidoData.setText(datenew);
myHolder.txtPedidoTotal.setText("R$ " + current.pTotal);
myHolder.edtPedido.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
mCallback.onProcessFilter(pedidos); //NullPointerException here
}
});
// load image into imageview using glide
concluido = "concluido";
cancelado = "cancelado";
em_andamento= "em_andamento";
status = current.pStatus;
if (status.equals(concluido)) {
Glide.with(context).load(R.drawable.ic_pedido_concluido).into(myHolder.imgPedidoStatus);
} else if (status.equals(cancelado)) {
Glide.with(context).load(R.drawable.ic_pedido_cancelado).into(myHolder.imgPedidoStatus);
}else if (status.equals(em_andamento)) {
Glide.with(context).load(R.drawable.ic_pedido_em_andamento).into(myHolder.imgPedidoStatus);
}
}
// return total item from List
#Override
public int getItemCount() {
return data.size();
}
class MyHolder extends RecyclerView.ViewHolder{
TextView txtPedidoNumero;
TextView txtPedidoCliente;
ImageView imgPedidoStatus;
TextView txtPedidoData;
TextView txtPedidoTotal;
ImageView edtPedido;
// create constructor to get widget reference
public MyHolder(View itemView) {
super(itemView);
txtPedidoNumero= (TextView) itemView.findViewById(R.id.txtPedidoNumero);
txtPedidoCliente= (TextView) itemView.findViewById(R.id.txtPedidoCliente);
imgPedidoStatus= (ImageView) itemView.findViewById(R.id.imgPedidoStatus);
txtPedidoData = (TextView) itemView.findViewById(R.id.txtPedidoData);
txtPedidoTotal = (TextView) itemView.findViewById(R.id.txtPedidoTotal);
edtPedido = (ImageView) itemView.findViewById(R.id.edtPedido);
}
}
}
FragmentoHistorico.java
public class FragmentoHistorico extends Fragment implements AdapterHistorico.IProcessFilter {
[...]
public void onProcessFilter(DataHistorico pedidos) {
EditarPedidoDialog(pedidos);
}
private void EditarPedidoDialog(final DataHistorico pedidos){
LayoutInflater inflater = LayoutInflater.from(getActivity());
final View subView = inflater.inflate(R.layout.layout_edt_pedido, null);
[...]
private class ProcurarPedido extends AsyncTask<String, String, String> {
ProgressDialog pdLoading = new ProgressDialog(getActivity());
HttpURLConnection conn;
URL url = null;
private String searchQuery;
private View rootView;
public ProcurarPedido(String searchQuery, View rootView){
this.searchQuery=searchQuery;
this.rootView=rootView;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
//this method will be running on UI thread
pdLoading.setMessage("\tAguarde...");
pdLoading.setCancelable(false);
pdLoading.show();
}
#Override
protected String doInBackground(String... params) {
try {
// Enter URL address where your php file resides
url = new URL(ADMIN_PANEL_URL + "public/procurar-pedido-app.php");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return e.toString();
}
try {
// Setup HttpURLConnection class to send and receive data from php and mysql
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("POST");
// setDoInput and setDoOutput to true as we send and recieve data
conn.setDoInput(true);
conn.setDoOutput(true);
// add parameter to our above url
Uri.Builder builder = new Uri.Builder().appendQueryParameter("searchQuery", searchQuery);
String query = builder.build().getEncodedQuery();
OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
writer.write(query);
writer.flush();
writer.close();
os.close();
conn.connect();
} 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 data 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);
}
// Pass data to onPostExecute method
return (result.toString());
} else {
return("Erro na conexão!");
}
} 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
Log.v("result", result);
pdLoading.dismiss();
ArrayList<DataHistorico> data=new ArrayList<>();
if(result.equals("no rows")) {
mRVHistoricoInfo = (RecyclerView)rootView.findViewById(R.id.ListaHistoricoInfo);
mAdapter = new AdapterHistorico(getActivity(), data, null);
mRVHistoricoInfo.setAdapter(mAdapter);
mRVHistoricoInfo.setLayoutManager(new LinearLayoutManager(getActivity()));
data.clear();
Toast.makeText(getActivity(), "Não foram encontrados pedidos pelo nome do cliente informado.", Toast.LENGTH_LONG).show();
}else{
try {
data.clear();
JSONArray jArray = new JSONArray(result);
// Extract data from json and store into ArrayList as class objects
for (int i = 0; i < jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
DataHistorico historicoData = new DataHistorico();
historicoData.pNumero= json_data.getString("nid");
historicoData.pStatus= json_data.getString("pedido_status");
historicoData.pCliente= json_data.getString("pedido_cliente");
historicoData.pEndereco= json_data.getString("pedido_endereco");
historicoData.pData= json_data.getString("pedido_data");
historicoData.pTotal= json_data.getString("pedido_total");
data.add(historicoData);
}
mRVHistoricoInfo = (RecyclerView)rootView.findViewById(R.id.ListaHistoricoInfo);
mAdapter = new AdapterHistorico(getActivity(), data, null);
mRVHistoricoInfo.setAdapter(mAdapter);
mRVHistoricoInfo.setLayoutManager(new LinearLayoutManager(getActivity()));
} catch (JSONException e) {
// You to understand what actually error is and handle it appropriately
Toast.makeText(getActivity(),"Não foi possível contatar o servidor.", Toast.LENGTH_LONG).show();
}
}
}
}
[...]
This is the error:
java.lang.NullPointerException: Attempt to invoke interface method
'void
com.beliasdev.cadjobel.adapter.AdapterHistorico$IProcessFilter.onProcessFilter(com.beliasdev.cadjobel.adapter.DataHistorico)'
on a null object reference
You are sending null instead of listener as a parameter:
So change
mAdapter = new AdapterHistorico(getActivity(), data, null);
To
mAdapter = new AdapterHistorico(getActivity(), data, this);
I'm new coder of android and trying to get list of images in my server and database(mysql) but I got error and I don't know what is causing it...
the error is 'E/RecyclerView: No adapter attached; skipping layout' and it happen when I'm running, anyone can help me??
public class LoadListFromServer extends AsyncTask<String, Void, String> {
private RecyclerView recyclerView;
private Context context;
private ArrayList<ImageGalleryItem> imageGalleryItems;
private boolean pattern;
public LoadListFromServer(RecyclerView recyclerView, Context context, boolean pattern) {
this.recyclerView = recyclerView;
this.context = context;
this.pattern = pattern;
}
public ArrayList<ImageGalleryItem> getImageGalleryItems() {
return imageGalleryItems;
}
#Override
protected String doInBackground(String... strings) {
URL url;
HttpURLConnection urlConnection = null;
try {
url = new URL(strings[0]);
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestProperty("Content-type", "application/json");
int responseCode = urlConnection.getResponseCode();
if(responseCode == HttpURLConnection.HTTP_OK){
return readStream(urlConnection.getInputStream());
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String response) {
super.onPostExecute(response);
recyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager = new GridLayoutManager(context,2);
recyclerView.setLayoutManager(layoutManager);
imageGalleryItems = prepareData(response);
MyAdapter adapter = new MyAdapter(context, imageGalleryItems);
recyclerView.setAdapter(adapter);
}
private String readStream(InputStream in) {
BufferedReader reader = null;
StringBuffer response = new StringBuffer();
try {
reader = new BufferedReader(new InputStreamReader(in, "UTF-8"), 8);
String line = "";
while ((line = reader.readLine()) != null) {
response.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return response.toString();
}
private ArrayList<ImageGalleryItem> prepareData(String response) {
ArrayList<ImageGalleryItem> result = null;
try {
JSONArray jsonArray = new JSONArray(response);
result = new ArrayList<>(jsonArray.length());
for (int i=0; i < jsonArray.length(); i++) {
try {
JSONObject oneObject = jsonArray.getJSONObject(i);
String id = oneObject.getString("id");
String name = oneObject.getString("name");
result.add(new ImageGalleryItem(name, Long.parseLong(id), pattern));
} catch (JSONException e) {
e.printStackTrace();
}
}
} catch (JSONException e) {
e.printStackTrace();
}
if(result == null) {
return new ArrayList<>();
} else {
return result;
}
}
}
I wrote my adapter as MyAdapter.java:
class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private ArrayList<ImageGalleryItem> galleryList;
public MyAdapter(Context context, ArrayList<ImageGalleryItem> galleryList) {
this.galleryList = galleryList;
}
#Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.cell_layout, viewGroup, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(MyAdapter.ViewHolder viewHolder, int i) {
final ImageGalleryItem imageGalleryItem = galleryList.get(i);
viewHolder.title.setText(imageGalleryItem.getName());
viewHolder.img.setScaleType(ImageView.ScaleType.FIT_XY);
String imageFolderName;
final boolean isPattern = imageGalleryItem.isPattern();
if(isPattern) {
imageFolderName = viewHolder.img.getContext().getString(R.string.patterns_directory);
} else {
imageFolderName = viewHolder.img.getContext().getString(R.string.collections_directory);
}
LoadSVGFromServer loadSVGFromServer = new LoadSVGFromServer(viewHolder.img);
loadSVGFromServer.execute(viewHolder.img.getContext().getString(R.string.server_base_address)
+ imageFolderName
+ imageGalleryItem.getID() + ".svg");
viewHolder.img.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Activity activity = (Activity) v.getContext();
if(isPattern) {
Intent intent = new Intent(activity, ColoringActivity.class);
Bundle b = new Bundle();
b.putSerializable(activity.getString(R.string.CURRENT_COLLECTION_BUNDLE_KEY), imageGalleryItem);
intent.putExtras(b);
activity.startActivity(intent);
} else {
Intent intent = new Intent(activity, ShowPatternsActivity.class);
Bundle b = new Bundle();
b.putSerializable(activity.getString(R.string.CURRENT_COLLECTION_BUNDLE_KEY), imageGalleryItem);
intent.putExtras(b);
activity.startActivity(intent);
}
}
});
}
#Override
public int getItemCount() {
return galleryList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder{
private TextView title;
private ImageView img;
public ViewHolder(View view) {
super(view);
title = (TextView)view.findViewById(R.id.title);
img = (ImageView) view.findViewById(R.id.img);
}
}
}
You can setup your recyclerView and set items when data received.
activity code for setup recycler view:
public class MainActivity extends AppCompatActivity {
private MyAdapter mAdapter;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setupRecyclerView();
}
private void setupRecyclerView(){
recyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager = new GridLayoutManager(context,2);
recyclerView.setLayoutManager(layoutManager);
mAdapter = new MyAdapter(context);
recyclerView.setAdapter(mAdapter);
}
}
Pass adapter to async task:
public class LoadListFromServer extends AsyncTask<String, Void, String> {
private MyAdapter mAdapter;
private Context context;
private ArrayList<ImageGalleryItem> imageGalleryItems;
private boolean pattern;
public LoadListFromServer(MyAdapter adapter, Context context, boolean pattern) {
this.mAdapter = adapter;
this.context = context;
this.pattern = pattern;
}
public ArrayList<ImageGalleryItem> getImageGalleryItems() {
return imageGalleryItems;
}
#Override
protected String doInBackground(String... strings) {
URL url;
HttpURLConnection urlConnection = null;
try {
url = new URL(strings[0]);
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestProperty("Content-type", "application/json");
int responseCode = urlConnection.getResponseCode();
if(responseCode == HttpURLConnection.HTTP_OK){
return readStream(urlConnection.getInputStream());
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String response) {
super.onPostExecute(response);
imageGalleryItems = prepareData(response);
mAdapter.setItems(imageGalleryItems);
}
private String readStream(InputStream in) {
BufferedReader reader = null;
StringBuffer response = new StringBuffer();
try {
reader = new BufferedReader(new InputStreamReader(in, "UTF-8"), 8);
String line = "";
while ((line = reader.readLine()) != null) {
response.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return response.toString();
}
private ArrayList<ImageGalleryItem> prepareData(String response) {
ArrayList<ImageGalleryItem> result = null;
try {
JSONArray jsonArray = new JSONArray(response);
result = new ArrayList<>(jsonArray.length());
for (int i=0; i < jsonArray.length(); i++) {
try {
JSONObject oneObject = jsonArray.getJSONObject(i);
String id = oneObject.getString("id");
String name = oneObject.getString("name");
result.add(new ImageGalleryItem(name, Long.parseLong(id), pattern));
} catch (JSONException e) {
e.printStackTrace();
}
}
} catch (JSONException e) {
e.printStackTrace();
}
if(result == null) {
return new ArrayList<>();
} else {
return result;
}
}
}
Adapter with setItems method:
class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private ArrayList<ImageGalleryItem> galleryList;
public MyAdapter(Context context) {
}
#Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.cell_layout, viewGroup, false);
return new ViewHolder(view);
}
public void setItems(ArrayList<ImageGalleryItem> galleryList){
this.galleryList = galleryList;
notifyDataSetChanged();
}
#Override
public void onBindViewHolder(MyAdapter.ViewHolder viewHolder, int i) {
final ImageGalleryItem imageGalleryItem = galleryList.get(i);
viewHolder.title.setText(imageGalleryItem.getName());
viewHolder.img.setScaleType(ImageView.ScaleType.FIT_XY);
String imageFolderName;
final boolean isPattern = imageGalleryItem.isPattern();
if(isPattern) {
imageFolderName = viewHolder.img.getContext().getString(R.string.patterns_directory);
} else {
imageFolderName = viewHolder.img.getContext().getString(R.string.collections_directory);
}
LoadSVGFromServer loadSVGFromServer = new LoadSVGFromServer(viewHolder.img);
loadSVGFromServer.execute(viewHolder.img.getContext().getString(R.string.server_base_address)
+ imageFolderName
+ imageGalleryItem.getID() + ".svg");
viewHolder.img.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Activity activity = (Activity) v.getContext();
if(isPattern) {
Intent intent = new Intent(activity, ColoringActivity.class);
Bundle b = new Bundle();
b.putSerializable(activity.getString(R.string.CURRENT_COLLECTION_BUNDLE_KEY), imageGalleryItem);
intent.putExtras(b);
activity.startActivity(intent);
} else {
Intent intent = new Intent(activity, ShowPatternsActivity.class);
Bundle b = new Bundle();
b.putSerializable(activity.getString(R.string.CURRENT_COLLECTION_BUNDLE_KEY), imageGalleryItem);
intent.putExtras(b);
activity.startActivity(intent);
}
}
});
}
#Override
public int getItemCount() {
return galleryList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder{
private TextView title;
private ImageView img;
public ViewHolder(View view) {
super(view);
title = (TextView)view.findViewById(R.id.title);
img = (ImageView) view.findViewById(R.id.img);
}
}
}
I tried to implement for adding more items to my adapter but its refreshing every time instead of adding new items to bottom of the list.I searched through the internet but i didn't get the solution Here is my code:
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Calendar;
public class MainActivity extends AppCompatActivity {
private DataListAdapter dataListAdapter;
Activity _activity;
ArrayList<DataObject> dataArrayList;
private ListView lv;
private String jsonResult;
boolean loadingMore = false;
private DataObject dataObject;
private static final String TAG = MainActivity.class.getSimpleName();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
_activity = this;
lv = (ListView) findViewById(R.id.listView1);
View footerView = ((LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(R.layout.loading_view, null, false);
this.lv.addFooterView(footerView);
if (isOnline(_activity)) {
new LoadJsonData().execute();
scrollNotifyChange();
}
}
private void scrollNotifyChange() {
lv.setOnScrollListener(new AbsListView.OnScrollListener() {
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
//what is the bottom item that is visible
int lastInScreen = firstVisibleItem + visibleItemCount;
//is the bottom item visible & not loading more already? Load more!
if ((lastInScreen == totalItemCount) && !(loadingMore)) {
// //start a new thread for loading the items in the list
Thread thread = new Thread(null, loadMoreListItems);
thread.start();
}
}
});
}
private Runnable loadMoreListItems = new Runnable() {
#Override
public void run() {
//Set flag so we cant load new items 2 at the same time
loadingMore = true;
//Reset the array that holds the new items
//Simulate a delay, delete this on a production environment!
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
}
jsonResult = doInBackground();
runOnUiThread(returnRes);
}
};
private Runnable returnRes = new Runnable() {
#Override
public void run() {
onPostExecute(jsonResult);
loadingMore = false;
}
};
public String doInBackground() {
String jsonResult = "";
// jsonResult=get("https://datatables.net/examples/server_side/scripts/server_processing.php");
// return jsonResult;
InputStream inputStream = null;
String result = "";
try {
HttpClient httpclient = new DefaultHttpClient();
HttpGet request = new HttpGet("https://datatables.net/examples/server_side/scripts/server_processing.php");
HttpResponse httpResponse = httpclient.execute(request);
inputStream = httpResponse.getEntity().getContent();
if (inputStream != null) {
jsonResult = convertInputStreamToString(inputStream);
} else {
jsonResult = "Did not work!";
}
} catch (Exception e) {
Log.e(TAG, "GET failed", e);
}
return jsonResult;
}
public void onPostExecute(String result) {
try {
// progress.dismiss();
dataArrayList = new ArrayList<DataObject>();
JSONObject dataJsontObject = new JSONObject(result);
JSONArray dataJsonArray = dataJsontObject.getJSONArray("data");
for (int i = 0; i < dataJsonArray.length(); i++) {
JSONArray dataSubArray = dataJsonArray.getJSONArray(i);
dataObject = new DataObject();
dataObject.setName((String) dataSubArray.get(0));
dataObject.setType((String) dataSubArray.get(1));
dataObject.setProfession((String) dataSubArray.get(2));
dataObject.setCountry((String) dataSubArray.get(3));
dataObject.setCurrency((String) dataSubArray.get(5));
dataArrayList.add(dataObject);
}
dataListAdapter = new DataListAdapter(dataArrayList);
dataListAdapter.add(dataObject);
// lv.setAdapter(dataListAdapter);
// dataListAdapter.add(dataObject);
dataListAdapter.notifyDataSetChanged();
lv.setAdapter(dataListAdapter);
lv.smoothScrollToPosition(dataListAdapter.getCount());
} catch (JSONException e) {
e.printStackTrace();
}
}
public static boolean isOnline(Context context) {
ConnectivityManager cm =
(ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
return netInfo != null && netInfo.isConnectedOrConnecting();
}
private class LoadJsonData extends AsyncTask<Void, Void, String> {
ProgressDialog progress;
#Override
protected void onPreExecute() {
super.onPreExecute();
progress = ProgressDialog.show(_activity, "Progress",
"Please wait", true);
}
#Override
protected String doInBackground(Void... params) {
String jsonResult = "";
// jsonResult=get("https://datatables.net/examples/server_side/scripts/server_processing.php");
// return jsonResult;
InputStream inputStream = null;
String result = "";
try {
HttpClient httpclient = new DefaultHttpClient();
HttpGet request = new HttpGet("https://datatables.net/examples/server_side/scripts/server_processing.php");
HttpResponse httpResponse = httpclient.execute(request);
inputStream = httpResponse.getEntity().getContent();
if (inputStream != null) {
jsonResult = convertInputStreamToString(inputStream);
} else {
jsonResult = "Did not work!";
}
} catch (Exception e) {
Log.e(TAG, "GET failed", e);
}
return jsonResult;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
try {
progress.dismiss();
if(loadingMore)
{
// listViwe.removeFooterView(loadingFooter);
loadingMore = false;
}
dataArrayList = new ArrayList<DataObject>();
JSONObject dataJsontObject = new JSONObject(result);
JSONArray dataJsonArray = dataJsontObject.getJSONArray("data");
for (int i = 0; i < dataJsonArray.length(); i++) {
JSONArray dataSubArray = dataJsonArray.getJSONArray(i);
DataObject dataObject = new DataObject();
dataObject.setName((String) dataSubArray.get(0));
dataObject.setType((String) dataSubArray.get(1));
dataObject.setProfession((String) dataSubArray.get(2));
dataObject.setCountry((String) dataSubArray.get(3));
dataObject.setCurrency((String) dataSubArray.get(5));
dataArrayList.add(dataObject);
}
dataListAdapter = new DataListAdapter(dataArrayList);
lv.setAdapter(dataListAdapter);
dataListAdapter.notifyDataSetChanged();
} catch (JSONException e) {
e.printStackTrace();
if(loadingMore)
{
// listViwe.removeFooterView(loadingFooter);
loadingMore = false;
}
}
}
}
public class DataListAdapter extends BaseAdapter {
ArrayList<DataObject> dataListObject = new ArrayList<DataObject>();
public DataListAdapter(ArrayList<DataObject> dataListObject) {
this.dataListObject = dataListObject;
}
#Override
public int getCount() {
return dataListObject.size();
}
#Override
public Object getItem(int position) {
return dataListObject.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
public void add(DataObject dataObject){
// Log.v("AddView", country.getCode());
this.dataListObject.add(dataObject);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
if (convertView == null) {
LayoutInflater inflater = LayoutInflater.from(_activity);
convertView = inflater.inflate(R.layout.single_row, null);
holder = new ViewHolder();
holder.name = (TextView) convertView.findViewById(R.id.name);
holder.type = (TextView) convertView.findViewById(R.id.type);
holder.profession = (TextView) convertView.findViewById(R.id.profession);
holder.country = (TextView) convertView.findViewById(R.id.country);
holder.currency = (TextView) convertView.findViewById(R.id.currecy);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
final DataObject current = dataListObject.get(position);
holder.name.setText("Name--" + current.getName());
holder.type.setText("Type--" + current.getType());
holder.profession.setText("Professoion--" + current.getProfession());
holder.country.setText("Country--" + current.getCountry());
holder.currency.setText("Currency--" + current.getCurrency());
return convertView;
}
}
static class ViewHolder {
TextView name;
TextView type;
TextView profession;
TextView country;
TextView currency;
}
public static String convertInputStreamToString(InputStream inputStream) throws IOException {
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
String line = "";
String result = "";
while ((line = bufferedReader.readLine()) != null) {
result += line;
}
inputStream.close();
return result;
}
}
you need to create an adapter inside onCreate method
like this:
ArrayList<DataObject> list;
onCreate() {
list=new ArrayList();
ListAdapter dataListAdapter =new ListAdapter(list) // creating an adapter with empty list of data
listView.setAdpater(adpater);
}
then, in onPostExceute() method :
add data to the ArrayList and notifythe adapter
like this:
onPostExecute(){
....
.....
list.add(dataObject); //here you can add 'n' number of object to the list
dataListAdapter.notifyDataSetChanged(); // notify the adapter to update the listview
.....
}
EDIT : I updated this answer as per #user3422948 request
DataListAdapter dataListAdapter;
ArrayList<DataObject> dataArrayList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
_activity = this;
//edit: declare your arraylist and adapter here
dataArrayList = new ArrayList<DataObject>();
dataListAdapter = new DataListAdapter(dataArrayList);
lv = (ListView) findViewById(R.id.listView1);
View footerView = ((LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(R.layout.loading_view, null, false);
this.lv.addFooterView(footerView);
if (isOnline(_activity)) {
new LoadJsonData().execute();
scrollNotifyChange();
}
}
......
.......
public void onPostExecute(String result) {
try {
// progress.dismiss();
//dataArrayList = new ArrayList<DataObject>(); //edit
JSONObject dataJsontObject = new JSONObject(result);
JSONArray dataJsonArray = dataJsontObject.getJSONArray("data");
for (int i = 0; i < dataJsonArray.length(); i++) {
JSONArray dataSubArray = dataJsonArray.getJSONArray(i);
dataObject = new DataObject();
dataObject.setName((String) dataSubArray.get(0));
dataObject.setType((String) dataSubArray.get(1));
dataObject.setProfession((String) dataSubArray.get(2));
dataObject.setCountry((String) dataSubArray.get(3));
dataObject.setCurrency((String) dataSubArray.get(5));
dataArrayList.add(dataObject);
}
//edit: your creating new adapter for every execution
//dataListAdapter = new DataListAdapter(dataArrayList);
//dataListAdapter.add(dataObject);
// lv.setAdapter(dataListAdapter);
// dataListAdapter.add(dataObject);
dataListAdapter.notifyDataSetChanged();
//lv.setAdapter(dataListAdapter);
lv.smoothScrollToPosition(dataListAdapter.getCount());
} catch (JSONException e) {
e.printStackTrace();
}
}
the problem is for every execution you are creating new Adapter
you should see this link how to use notifyDataSetChanged in listView
AsyncTask spawns a new intelligent thread on its own, runs things in background and also posts results of UI thread in onPostExecute method.
You should not call the methods of AsyncTask on your own. Android does it by itself. Instead of calling a new thread in scrollchangelistener,like:
Thread thread = new Thread(null, loadMoreListItems);
call
new LoadJsonData().execute();
you don't need two Runnable threads to do the same thing your asyncTask does.
The problem is this code of yours:
dataListAdapter = new DataListAdapter(dataArrayList);
lv.setAdapter(dataListAdapter);
Every time your scrolling reaches the end, it eventually calls the onPostExecute method to post results on the UI. But here you are making a new Adapter eveytime with a new dataset which is why it always refreshes the whole list.
Remove this part and set it inside onCreate of your Activity.Add new values to your adapter's datalist in onPostExecute.
Then just do a notifyDataSetChanged inside onPostExecute of your AsyncTask.
I'm trying to pass an Arraylist with Objects obtained from a JSON, and pass to another fragment in Android Studio.
Here is the class that i want to receive the array
#Override
public View onCreateView(LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_car, container, false);
new AsyncTaskParseJson().execute();
mRecyclerView = (RecyclerView) view.findViewById(R.id.rv_list);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.addOnItemTouchListener(new RecyclerViewTouchListener( getActivity(), mRecyclerView, this ));
LinearLayoutManager llm = new LinearLayoutManager(getActivity());
llm.setOrientation(LinearLayoutManager.VERTICAL);
mRecyclerView.setLayoutManager(llm);
CarAdapter adapter = new CarAdapter(getActivity(), mList);
mRecyclerView.setAdapter( adapter );
return view;
}
That is my class that is creating the array:
public class AsyncTaskParseJson extends AsyncTask<String, String, String> {
final String TAG = "AsyncTaskParseJson.java";
String yourJsonStringUrl = "http://marciowelben.servidorturbo.net/getjson.php";
JSONArray dataJsonArr = null;
#Override
protected void onPreExecute() {}
#Override
protected String doInBackground(String... arg0) {
try {
JsonParser jParser = new JsonParser();
JSONObject json = jParser.getJSONFromUrl(yourJsonStringUrl);
dataJsonArr = json.getJSONArray("emp_info");
for (int i = 0; i < dataJsonArr.length(); i++) {
JSONObject c = dataJsonArr.getJSONObject(i);
// Storing each json item in variable
String firstname = c.getString("employee name");
String lastname = c.getString("employee no");
Car d = new Car(firstname, lastname, R.mipmap.ic_launcher );
listAux.add(d);
}
} catch (JSONException e) {
e.printStackTrace();
}
mList = listAux;
return null;
}
}
So i just want to populate my Recyclerview with this array.
Since you are adding the adapter first before waiting for the data to return you will have to call notifyDataSetChanged() for the adapter to redraw the list after it is done parsing. Another way of accomplishing this is waiting for the result to come back and then set the adapter. See below
public class MainActivity extends AppCompatActivity {
private static final String TAG = "RecyclerViewExample";
private List<FeedItem> feedItemList = new ArrayList<FeedItem>();
private RecyclerView mRecyclerView;
private MyRecyclerAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/* Initialize recyclerview */
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
/*Downloading data from below url*/
final String url = "http://javatechig.com/api/get_category_posts/?dev=1&slug=android";
new AsyncHttpTask().execute(url);
}
public class AsyncHttpTask extends AsyncTask<String, Void, Integer> {
#Override
protected void onPreExecute() {
setProgressBarIndeterminateVisibility(true);
}
#Override
protected Integer doInBackground(String... params) {
InputStream inputStream = null;
Integer result = 0;
HttpURLConnection urlConnection = null;
try {
/* forming th java.net.URL object */
URL url = new URL(params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
/* for Get request */
urlConnection.setRequestMethod("GET");
int statusCode = urlConnection.getResponseCode();
/* 200 represents HTTP OK */
if (statusCode == 200) {
BufferedReader r = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
StringBuilder response = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
response.append(line);
}
parseResult(response.toString());
result = 1; // Successful
}else{
result = 0; //"Failed to fetch data!";
}
} catch (Exception e) {
Log.d(TAG, e.getLocalizedMessage());
}
return result; //"Failed to fetch data!";
}
#Override
protected void onPostExecute(Integer result) {
setProgressBarIndeterminateVisibility(false);
/* Download complete. Lets update UI */
if (result == 1) {
adapter = new MyRecyclerAdapter(MainActivity.this, feedItemList);
mRecyclerView.setAdapter(adapter);
} else {
Log.e(TAG, "Failed to fetch data!");
}
}
}
private void parseResult(String result) {
try {
JSONObject response = new JSONObject(result);
JSONArray posts = response.optJSONArray("posts");
/*Initialize array if null*/
if (null == feedItemList) {
feedItemList = new ArrayList<FeedItem>();
}
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.optJSONObject(i);
FeedItem item = new FeedItem();
item.setTitle(post.optString("title"));
item.setThumbnail(post.optString("thumbnail"));
feedItemList.add(item);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
1.Design Recycleview in layout
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingTop="10dp"
android:layout_weight="1"
/>
2.add dependency in gradle.build
compile 'com.android.support:recyclerview-v7:23.1.1'
3.Write the code in Activity
public class DoctorInformationActivity extends AppCompatActivity {
String URL="YOUR URL";
JSONArray Cities=null;
ArrayList<DocotorInformation> doctorList =new ArrayList<DocotorInformation>();
Sqlitedatabase sql;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.doctor_information_listview);
sql=new Sqlitedatabase(getApplicationContext());
ConnectivityManager connectivityManager
= (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
if(activeNetworkInfo != null && activeNetworkInfo.isConnected())
{
Toast.makeText(getApplicationContext()," connect",Toast.LENGTH_LONG).show();
new JSONAsyncTask().execute();
}
else
{
ArrayList<DocotorInformation> listdata=sql.getAllContacts();
doctorList=listdata;
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
DoctorAdapter mAdapter = new DoctorAdapter(getApplicationContext(), doctorList);
recyclerView.setAdapter(mAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
Toast.makeText(getApplicationContext(),"Not connect",Toast.LENGTH_LONG).show();
}
}
private class JSONAsyncTask extends AsyncTask<String, Void, JSONArray> {
private ProgressDialog dialog = new ProgressDialog(DoctorInformationActivity.this);
#Override
protected void onPreExecute() {
this.dialog.setMessage("Please wait");
this.dialog.show();
}
#Override
protected JSONArray doInBackground(String... urls) {
try {
//------------------>>
HttpGet httppost = new HttpGet(URL);
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = httpclient.execute(httppost);
// StatusLine stat = response.getStatusLine();
int status = response.getStatusLine().getStatusCode();
if (status == 200) {
HttpEntity entity = response.getEntity();
String data = EntityUtils.toString(entity);
JSONObject jsono = new JSONObject(data);
Cities = jsono.getJSONArray("SearchDoctorsData");
return Cities;
}
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
return Cities;
}
protected void onPostExecute(JSONArray result) {
dialog.dismiss();
System.out.println(result);
for (int i = 0; i < result.length(); i++) {
JSONObject c = null;
try {
DocotorInformation doc=new DocotorInformation();
c = result.getJSONObject(i);
doc.setName(c.getString("DoctorName"));
doc.setNumber(c.getString("Mobile"));
doctorList.add(doc);
sql.insertData(doc);
} catch (JSONException e) {
e.printStackTrace();
}
}
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
DoctorAdapter mAdapter = new DoctorAdapter(getApplicationContext(), doctorList);
recyclerView.setAdapter(mAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
}
}
}
public class DoctorAdapter extends RecyclerView.Adapter<DoctorAdapter.ViewHolder> {
private ArrayList<DocotorInformation> countries;
Context con;
public DoctorAdapter(Context c ,ArrayList<DocotorInformation> countries) {
this.con=c;
this.countries = countries;
}
#Override
public DoctorAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.doctor_textviews, viewGroup, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(DoctorAdapter.ViewHolder viewHolder, int i) {
viewHolder.name.setText(countries.get(i).getName());
viewHolder.number.setText(countries.get(i).getNumber());
}
#Override
public int getItemCount() {
return countries.size();
}
public class ViewHolder extends RecyclerView.ViewHolder{
private TextView name,number;
public ViewHolder(View view) {
super(view);
name = (TextView)view.findViewById(R.id.name);
number = (TextView)view.findViewById(R.id.numebr);
}
}
}
I am trying to get a response from a service (the response comes in json).
I made my checks if the device is connected and now I need to make the http request to the service. I found out on other questions that I have to use a background thread but I am not sure I got a working sample.
So I need to find out how I can make a connection to a given uri and read the response.
My service needs to get a content header application/json in orderto return a json, so before the request I need to set this header as well.
Thank you in advance
UPDATE
package com.example.restfulapp;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.provider.Settings;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.concurrent.ExecutionException;
public class MainActivity extends Activity {
private int code = 0;
private String value = "";
private ProgressDialog mDialog;
private Context mContext;
private String mUrl ="http://192.168.1.13/myservice/upfields/";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (!isOnline())
{
displayNetworkOption ("MyApp", "Application needs network connectivity. Connect now?");
}
try {
JSONObject s = getJSON(mUrl);
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
public class Get extends AsyncTask<Void, Void, String> {
#Override
protected String doInBackground(Void... arg) {
String linha = "";
String retorno = "";
mDialog = ProgressDialog.show(mContext, "Please wait", "Loading...", true);
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(mUrl);
try {
HttpResponse response = client.execute(get);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) { // Ok
BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
while ((linha = rd.readLine()) != null) {
retorno += linha;
}
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return retorno;
}
#Override
protected void onPostExecute(String result) {
mDialog.dismiss();
}
}
public JSONObject getJSON(String url) throws InterruptedException, ExecutionException {
setUrl(url);
Get g = new Get();
return createJSONObj(g.get());
}
private void displayNetworkOption(String title, String message){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder
.setTitle(title)
.setMessage(message)
.setPositiveButton("Wifi", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
startActivity(new Intent(Settings.ACTION_WIFI_SETTINGS));
}
})
.setNeutralButton("Data", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
startActivity(new Intent(Settings.ACTION_DATA_ROAMING_SETTINGS));
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
return;
}
})
.show();
}
private boolean isOnline() {
ConnectivityManager cm =
(ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
if (netInfo != null && netInfo.isConnectedOrConnecting()) {
return true;
}
return false;
}
}
This throws errors:
Gradle: cannot find symbol method setUrl(java.lang.String)
Gradle: cannot find symbol method createJSONObj(java.lang.String)
After derogatory responses from EvZ who think that he was born knowing everything, I ended up with a subclass MyTask that I call like this inside the onCreate of my Activity.
new MyTask().execute(wserviceURL);
private class MyTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
URL myurl = null;
try {
myurl = new URL(urls[0]);
} catch (MalformedURLException e) {
e.printStackTrace();
}
URLConnection connection = null;
try {
connection = myurl.openConnection();
} catch (IOException e) {
e.printStackTrace();
}
connection.setConnectTimeout(R.string.TIMEOUT_CONNECTION);
connection.setReadTimeout(R.string.TIMEOUT_CONNECTION);
HttpURLConnection httpConnection = (HttpURLConnection) connection;
httpConnection.setRequestProperty("Content-Type", getString(R.string.JSON_CONTENT_TYPE));
int responseCode = -1;
try {
responseCode = httpConnection.getResponseCode();
} catch (SocketTimeoutException ste) {
ste.printStackTrace();
}
catch (Exception e1) {
e1.printStackTrace();
}
if (responseCode == HttpURLConnection.HTTP_OK) {
StringBuilder answer = new StringBuilder(100000);
BufferedReader in = null;
try {
in = new BufferedReader(new InputStreamReader(httpConnection.getInputStream()));
} catch (IOException e) {
e.printStackTrace();
}
String inputLine;
try {
while ((inputLine = in.readLine()) != null) {
answer.append(inputLine);
answer.append("\n");
}
} catch (IOException e) {
e.printStackTrace();
}
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
httpConnection.disconnect();
return answer.toString();
}
else
{
//connection is not OK
httpConnection.disconnect();
return null;
}
}
#Override
protected void onPostExecute(String result) {
String userid = null;
String username = null;
String nickname = null;
if (result!=null)
{
try {
//do read the JSON here
} catch (JSONException e) {
e.printStackTrace();
}
}
//stop loader dialog
mDialog.dismiss();
}
}
lory105's answer guided me to somewhere near the answer, thanx.
here is an example of how to process the HTTP response and convert to JSONObject:
/**
* convert the HttpResponse into a JSONArray
* #return JSONObject
* #param response
* #throws IOException
* #throws IllegalStateException
* #throws UnsupportedEncodingException
* #throws Throwable
*/
public static JSONObject processHttpResponse(HttpResponse response) throws UnsupportedEncodingException, IllegalStateException, IOException {
JSONObject top = null;
StringBuilder builder = new StringBuilder();
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
for (String line = null; (line = reader.readLine()) != null;) {
builder.append(line).append("\n");
}
String decoded = new String(builder.toString().getBytes(), "UTF-8");
Log.d(TAG, "decoded http response: " + decoded);
JSONTokener tokener = new JSONTokener(Uri.decode(builder.toString()));
top = new JSONObject(tokener);
} catch (JSONException t) {
Log.w(TAG, "<processHttpResponse> caught: " + t + ", handling as string...");
} catch (IOException e) {
Log.e(TAG, "caught: " + e, e);
} catch (Throwable t) {
Log.e(TAG, "caught: " + t, t);
}
return top;
}
From Android 3+, the http connections must be done within a separate thread. Android offers a Class named AsyncTask that help you do it.
Here you can find a good example of an AsyncTask that performs an http request and receives a JSON response.
Remember that in the doInBackgroud(..) method you CAN'T modify the UI such as to launch a Toast, to change activity or others. You have to use the onPreExecute() or onPostExecute() methods to do this.
ADD
For the mDialog and mContext variables, add the code below, and when you create the JSONTask write new JSONTask(YOUR_ACTIVITY)
public abstract class JSONTask extends AsyncTask<String, Void, String> {
private Context context = null;
ProgressDialog mDialog = new ProgressDialog();
public JSONTask(Context _context){ context=_context; }
..