its my json file
{"VisitorsList":[{"VisitorID":"09005451","VisitorName":" xxxx","VisitorPhon":"","VisitorAddr":"xxxx","GeoCode":"","AutoKey":1},{"VisitorID":"09005468","VisitorName":"xxxxxx","VisitorPhon":"09005468","VisitorAddr":"xxxx","GeoCode":"","AutoKey":2}]}
and i wanna read and show information from this file to a ListView
my VisitorsListActivity is:
public class VisitorsListActivity extends AppCompatActivity {
public ListView lstVisitors;
static VisitorsList visitorsList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.visitor_list);
try {
//********************************** COMELETE THIS SECTION *********************************************
new JsonHelper.GetJsonData(new JsonHelper.GetJsonData.AsyncResponse() {
#Override
public void processFinish(String output) {
try {
if (output == null) output = "";
if (output.equals("")) {
Toast.makeText(getApplicationContext(),
"No Visitor Founded",
Toast.LENGTH_LONG)
.show();
return;
}
//960105--------------------
else if (output.equals("401")) {
Toast.makeText(getApplicationContext(),
"Error 401",
Toast.LENGTH_LONG)
.show();
return;
}
//--------------------------------------
Log.i("LOG", "output" + output);
Gson gson = new Gson();
output = output.substring(1, output.length() - 1);
/*Toast.makeText(getApplicationContext(),
output,
Toast.LENGTH_LONG)
.show();*/
visitorsList = new VisitorsList();
visitorsList = gson.fromJson(output, VisitorsList.class);
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(),
"exception",
Toast.LENGTH_LONG)
.show();
}
}
}).execute("http://192.168.1.162:8014/api/Visitors");
//************************************ visitor list is null :| *******************************************
/*if( visitorsList == null) {
Toast.makeText(getApplicationContext(),
"data is nul",
Toast.LENGTH_LONG)
.show();
}*/
AdapterVisitor customAdapter = new AdapterVisitor(this, R.layout.visitor_list, visitorsList.VisitorsList);
customAdapter.notifyDataSetChanged();
lstVisitors.setAdapter(customAdapter);
lstVisitors.requestFocus();
final ViewGroup layoutClear = (ViewGroup) findViewById(R.id.layoutClear);
layoutClear.setVisibility(View.GONE);
} catch (Exception e) {
e.getMessage();
}
} }
and VisitorsList:
public class VisitorsList {
public VisitorsList() {}
public ArrayList<Visitors> VisitorsList;}
Visitors:
public class Visitors {
public String VisitorID;
public String VisitorName;
public String VisitorPhon;
public String VisitorAddr;
public String GeoCode;
public int AutoKey;}
and always visitor list which created by Gson is null. i dont know maybe my problem is in reading from json or maybe visitors class ...
jsonhelper :
public class JsonHelper {
public static class GetJsonData extends AsyncTask<String, Void, String> {
public interface AsyncResponse {
void processFinish(String output);
}
public AsyncResponse delegate = null;
public GetJsonData(AsyncResponse delegate) {
this.delegate = delegate;
}
#Override
protected String doInBackground(String... strUrl) {
String str = strUrl[0];
URLConnection urlConn = null;
BufferedReader bufferedReader = null;
try {
URL url = new URL(str);
urlConn = url.openConnection();
urlConn.setReadTimeout(300000);
urlConn.setConnectTimeout(5000);
bufferedReader = new BufferedReader(new InputStreamReader(urlConn.getInputStream(), "utf-8"), 8);
StringBuffer stringBuffer = new StringBuffer();
String line;
while ((line = bufferedReader.readLine()) != null) {
stringBuffer.append(line);
}
String tmpJson = stringBuffer.toString().replace("\\", "");
return tmpJson;
} catch (Exception ex) {
ex.getMessage();
return null;
} finally {
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
#Override
protected void onPostExecute(String response) {
delegate.processFinish(response);
}
}
public static class SetJsonData extends AsyncTask<String, Void, String> {
String responseServer;
public interface AsyncResponse {
void processFinish(String output);
}
public AsyncResponse delegate = null;
public SetJsonData(AsyncResponse delegate) {
this.delegate = delegate;
}
#Override
protected String doInBackground(String... param) {
URL url;
String response = null;
try {
url = new URL(param[0]);
HttpURLConnection conn = null;
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(20000);
conn.setConnectTimeout(10000);//950718
conn.setRequestMethod("GET");
conn.setDoInput(true);
conn.setDoOutput(true);
OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
writer.write(param[1]);
writer.flush();
writer.close();
os.close();
int responseCode = conn.getResponseCode();
if (responseCode == HttpsURLConnection.HTTP_OK) {
String line;
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line = br.readLine()) != null) {
response += line;
}
} else {
response = (String.valueOf(responseCode));
String line;
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getErrorStream()));//950427
while ((line = br.readLine()) != null) {
}
}
return response;
} catch (IOException e1) {
e1.getMessage();
return null;
} catch (Exception e) {
e.getMessage();
return null;
}
}
#Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
try {
super.onPostExecute(result);
delegate.processFinish(result);
} catch (Exception e) {
e.getMessage();
}
}
}}
your visitors class is missing annotations.
use this to convert it properly:
http://www.jsonschema2pojo.org/
Check this https://kylewbanks.com/blog/Tutorial-Android-Parsing-JSON-with-GSON
to read the JSON with GSON.
well at first read AsyncResponse so you are using asynchronous request is that what are doing ?
An asynchronous request doesn't block the client so it continue executing the code when the response is back it will execute what is inside the callback.
But you are calling the customAdapter.notifyDataSetChanged(); outside processFinish() you need to call it inside or call the Adapter work inside the processFinish method.
public class VisitorsList {
public VisitorsList() {}
public ArrayList VisitorsList= new ArrayList<>();}
Should be like this... Intialization is missing.
VisitorsList class :
public class VisitorsList {
#SerializedName("VisitorsList")
public List<VisitorsList> VisitorsList;
public static class VisitorsList {
#SerializedName("VisitorID")
public String VisitorID;
#SerializedName("VisitorName")
public String VisitorName;
#SerializedName("VisitorPhon")
public String VisitorPhon;
#SerializedName("VisitorAddr")
public String VisitorAddr;
#SerializedName("GeoCode")
public String GeoCode;
#SerializedName("AutoKey")
public int AutoKey;
}
}
delete this line
output = output.substring(1, output.length() - 1);
and get your result:
Gson gson = new Gson();
visitorsList=gson.fromJson(output), new TypeToken<VisitorsList>() { }.getType());
i change VisitorsListActivity same as below . and set a condition before call adapter to be sure reading information from json has been finished, this worked correctly :
new JsonHelper.GetJsonData(new JsonHelper.GetJsonData.AsyncResponse() {
#Override
public void processFinish(String output) {
try {
if (output == null) output = "";
if (output.equals("")) {
Toast.makeText(getApplicationContext(),
"No Visitor Founded",
Toast.LENGTH_LONG)
.show();
return;
}
else if (output.equals("401")) {
Toast.makeText(getApplicationContext(),
"Error 401",
Toast.LENGTH_LONG)
.show();
return;
}
Log.i("LOG", "output" + output);
Gson gson = new Gson();
output = output.substring(1, output.length() - 1);
try {
visitorsList = new VisitorsList();
visitorsList = gson.fromJson(output, VisitorsList.class);
if(visitorsList != null) {
d.cancel();
adapter = new AdapterVisitor(visitorsList.VisitorsList);
adapter.notifyDataSetChanged();
lstVisitors.setAdapter(adapter);
lstVisitors.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// ******
Object o = lstVisitors.getItemAtPosition(position);
Intent i = new Intent(getApplicationContext(),DateSelectorActivity.class);
Visitors v = (Visitors) o;
i.putExtra("VisitorID", v.VisitorID);
startActivity(i);
}
});
}
}catch (Exception e) {
Log.i("LOG", getAssets().toString() + "exception" + e);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}).execute(url);
Related
I try to create synchronized threads, but I always get the following error: android.os.NetworkOnMainThreadException.
I've read more posts, but they don't work for me.
Below I write the code blocks that do not work for me:
1.
final SyncApp syncJob = new SyncApp();
Thread t = new Thread (new Runnable () {
#Override
public void run () {
synchronized (syncJob) {
String s = syncJob.insert (newJobs, GlobalVariables.URL_LOCALHOST + "jobs");
txtState.setText (s);
}}});
}
});
t.Start ();
// t.run ();
2.
myClass.runOnUiThread(new Runnable() {
public void run() {...}
})
3.
Running code in main thread from another thread
SyncApp:
public class SyncApp {
synchronized public String insert(List<Jobs> job, String... params) {
URL url = null;
HttpURLConnection conn = null;
try {
url = new URL(params[0]);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json");
conn.setDoInput(true);
conn.setDoOutput(true);
String str = new Gson().toJson(job);
byte[] outputInBytes = str.getBytes();
OutputStream os = conn.getOutputStream();
os.write( outputInBytes );
os.flush();
int responseCode=conn.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
String line;
BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line=br.readLine()) != null) {
response+=line;
}
}
else {
response=conn.getResponseMessage();
}
return response;
} catch (Exception e) {
e.printStackTrace();
} finally {
conn.disconnect();
}
return null;
}
}
I need to call a thread, wait for the answer and call another thread. Their answers I must use them in the activity
I need to call a thread, wait for the answer and call another thread.
Their answers I must use them in the activity
Example using async tasks to accomplish objective.
In this code, let A be your activity which needs to call a thread,
wait for the answer and call another thread. Customize as needed.
Since you never wait in UI threads, callbacks are used to accomplish synchronization.
Let A be your activity class:
public class A extends Activity {
// some method in activity where you launch a background thread (B)
// which then completes and invokes callback which then creates and launches
// a background thread (C) which then completes and invokes a callback.
//
// In callback C, you are on the UI thread.
protected void someMethod() {
new B(new B.CallbackB() {
public void result(Object o) {
new C(new C.CallbackC() {
public void result(Object o, Object answerFromB) {
// OK - C is now done and we are on UI thread!
// 'o' is answer from C
// 'answerFromB' also provided
}
}, o).execute(new Object());
}
).execute(new Object());
}
}
Define a class B:
public class B extends AsyncTask<Object, Void, Object> {
public static interface CallbackB {
void result(Object o);
}
private CallbackB cb;
public B (CallbackB cb) {
this.cb = cb;
}
protected Object doInBackground(Object... params) {
// do work and return an answer.
return new Object();
}
protected void onPostExecute(Object result) {
if (cb != null) {
cb.result(result);
}
}
}
Define a class C:
public class C extends AsyncTask<Object, Void, Object> {
public static interface CallbackC {
void result(Object o, Object answerFromB);
}
private CallbackC cb;
private Object answerFromB;
public C (CallbackC cb, Object answerFromB) {
this.cb = cb;
this.answerFromB = answerFromB;
}
protected Object doInBackground(Object... params) {
// do work and return an answer.
return new Object();
}
protected void onPostExecute(Object result) {
if (cb != null) {
cb.result(result, answerFromB);
}
}
}
For reference:
https://stackoverflow.com/a/9963705/2711811
My solution is:
public class Sync extends AppCompatActivity {
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sync_server);
dao = new DAO(this);
txtState = findViewById(R.id.txt_log);
btnSincro = findViewById(R.id.btn_sincro);
btnSincro.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
countCall = 0;
callFlow();
}
});
btnHome = findViewById(R.id.btn_home);
btnHome.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(SyncServerActivity.this, MainActivity.class);
startActivity(intent);
}
});
}
private void callFlow() {
switch (countCall) {
case 0:
templates = toTemplate("url");
break;
case 1:
jobs = toJobs("url");
break;
case 2:
job = ... //select item
res = sendJobs(jobs, "url");
break;
default:
runOnUiThread(new Runnable() {
#Override
public void run() {
btnSincro.setEnabled(true);
txtState.append("\n\nEND");
}
});
}
}
private void nextStep() {
setText(txtState, "\nSync \n" + countCall + "/3");
countCall++;
callFlow();
}
private void setText(final TextView text, final String value) {
runOnUiThread(new Runnable() {
#Override
public void run() {
text.setText(value);
}
});
}
public List<Templates> toTemplate(final String... params) {
final List<Templates> list = new ArrayList<>();
Thread t = new Thread(new Runnable() {
#Override
public void run() {
URL url = null;
BufferedReader reader = null;
HttpURLConnection connection = null;
try {
url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
int responseCode = connection.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
String finalJson = buffer.toString();
JSONObject parentObject = new JSONObject(finalJson);
JSONArray parentArray = parentObject.getJSONArray("data");
for (int i = 0; i < parentArray.length(); i++) {
Templates item = new Gson().fromJson(parentArray.get(i).toString(), Templates.class);
list.add(item);
}
} else {
response = connection.getResponseMessage();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null)
connection.disconnect();
try {
if (reader != null)
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
nextStep(); //call next Thread
}
}
});
t.start();
return list;
}
public List<Jobs> toJobs(final String... params) {
final List<Jobs> list = new ArrayList<>();
Thread t = new Thread(new Runnable() {
#Override
public void run() {
URL url = null;
BufferedReader reader = null;
HttpURLConnection connection = null;
try {
url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
int responseCode = connection.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
String finalJson = buffer.toString();
JSONObject parentObject = new JSONObject(finalJson);
JSONArray parentArray = parentObject.getJSONArray("data");
for (int i = 0; i < parentArray.length(); i++) {
Jobs item = new Gson().fromJson(parentArray.get(i).toString(), Jobs.class);
list.add(item);
}
} else {
response = connection.getResponseMessage();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null)
connection.disconnect();
try {
if (reader != null)
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
nextStep();
}
}
});
t.start();
return list;
}
public Boolean sendJobs(final List<Jobs> job, final String... params) {
final Boolean[] result = {false};
Thread t = new Thread(new Runnable() {
#Override
public void run() {
URL url = null;
HttpURLConnection conn = null;
try {
url = new URL(params[0]);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json");
conn.setDoInput(true);
conn.setDoOutput(true);
String str = new Gson().toJson(job);
Log.d(TAG, str);
byte[] outputInBytes = str.getBytes();
OutputStream os = conn.getOutputStream();
os.write(outputInBytes);
os.flush();
int responseCode = conn.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
String line;
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line = br.readLine()) != null) {
response += line;
}
result[0] = true;
} else {
response = conn.getResponseMessage();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
conn.disconnect();
nextStep();
}
}
});
t.start();
return result[0];
}
}
Whenever a thread ends, it calls the nextStep() method, which starts the next trhead.
I am a newbie in android and I've been working around pagination with recyclercview. I am receiving my data from a server(running php) and returning it in a JSON format which brings the data in bunches like 1-10, 11-20... so on. I call notifyDataSetChanged with this. But the problem is recyclerview scrolls back to the top when retrieving more data instead of retaining the current position. How do I go about this?
When scrollbar gets to the bottom, it triggers the asynctask
AsynTask:
public class LoadRecharge extends AsyncTask<String, String, String> {
private boolean socketTimeout = false;
Context context;
public static final String TAG = "custom_message";
public AsyncResponse delegate = null;
private String server_url = "https://blockgator.com/mobile/endless.php";
public LoadRecharge(Context ctxt, AsyncResponse asyncResponse) {
delegate = asyncResponse;
context = ctxt;
}
#Override
protected String doInBackground(String... params) {
if (connectGoogle()) {
String post_data = "";
try {
URL url = new URL(server_url);
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setDoOutput(true);
httpURLConnection.setDoInput(true);
OutputStream outputStream = httpURLConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
post_data = URLEncoder.encode("page", "UTF-8") + "=" + URLEncoder.encode(params[0], "UTF-8");
bufferedWriter.write(post_data);
bufferedWriter.flush();
outputStream.close();
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"));
String result = "";
String line = "";
while ((line = bufferedReader.readLine()) != null) {
result += line;
}
bufferedReader.close();
inputStream.close();
httpURLConnection.disconnect();
return result;
} catch (IOException e) {
Log.e(TAG, "error: " + e.getMessage());
}
} else {
this.socketTimeout = true;
}
return null;
}
#Override
protected void onPreExecute() {
arr.add(null);
scrollAdapter.notifyItemInserted(arr.size() - 1);
}
#Override
protected void onPostExecute(String result) {
arr.remove(arr.size() - 1);
scrollAdapter.notifyItemRemoved(arr.size());
if (this.socketTimeout) {
Toast.makeText(context, "unable to connect to server", Toast.LENGTH_SHORT).show();
} else {
delegate.processFinish(result);
}
}
public boolean connectGoogle() {
try {
HttpURLConnection urlc = (HttpURLConnection) (new URL("http://www.google.com").openConnection());
urlc.setConnectTimeout(3000);
urlc.connect();
return (urlc.getResponseCode() == 200);
} catch (IOException e) {
e.printStackTrace();
return false;
}
}
}
#Override
public void processFinish(String output) {
try {
JSONObject jsonObject = new JSONObject(output);
if (jsonObject.get("status").toString().equals("success")) {
JSONArray jsonarr = jsonObject.getJSONArray("data");
String columns[] = {"id", "bill_amount", "bill_price", "variation"};
for (int i = 0; i < jsonarr.length(); i++) {
ArrayList<String> temp = new ArrayList<>();
for (String column : columns) {
temp.add(jsonarr.getJSONObject(i).getString(column));
}
arr.add(temp);
setAdapter(arr);
}
} else if (jsonObject.get("status").toString().equals("end")) {
total = "end";
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(this, "exception from json", Toast.LENGTH_LONG).show();
} catch (NullPointerException e) {
Toast.makeText(this, "Unable to connect to server...", Toast.LENGTH_LONG).show();
Toast.makeText(this, "Null from json", Toast.LENGTH_LONG).show();
}
}
public void setAdapter(ArrayList<ArrayList<String>> arr) {
recycler.setAdapter(scrollAdapter);
scrollAdapter.notifyDataSetChanged();
scrollAdapter.setLoading();
scrollAdapter.setOnItemClickListener(this);
scrollAdapter.setOnLoadMoreListener(this);
}
Remove this line recycler.setAdapter(scrollAdapter); You need to set your adapter just once either in Activity's onCreate method or Fragment's onCreateView method.
In setAdapter() you dont need to do recycler.setAdapter(scrollAdapter); again, just do it at the beginning
I do something similar, but reversed, working as chat
messages.addAll(0, oldMessages);
mAdapter.notifyItemRangeInserted(0, oldMessages.size());
mAdapter.notifyItemChanged(oldMessages.size());
mAdapter.setLoaded();
Im adding the old messages of the char to the messages.
Then notifing the adapter I have updated the source
I uses the 0 to put at the beginning
public class GetPlaceSearchTask extends AsyncTask<String , Void ,String>
{
private Context context;
private ProgressDialog dialog;
public static final String SEND_RESULT_SEARCH_BROADCAST_FROM_TASK = "send_result_search";
private String API_LOCATION = "https://maps.googleapis.com/maps/api/place/nearbysearch/" +
"json?location=-33.8670522,151.1957362&radius=500&type=restaurant&name=cruise&key=";
public GetPlaceSearchTask(Context context) {
this.context = context;
}
protected void onPreExecute() {
if (context != null) {
dialog = new ProgressDialog(context);
dialog.setTitle("Downloading");
dialog.show();
}
}
#Override
protected String doInBackground(String... params) {
HttpsURLConnection connection = null;
BufferedReader reader = null;
StringBuilder builder = new StringBuilder();
try {
URL url = new URL(String.format(API_LOCATION, params[0], params[1]));
connection = (HttpsURLConnection) url.openConnection();
if (connection.getResponseCode() != HttpsURLConnection.HTTP_OK) {
return null;
}
reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
builder.append(line);
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
if (connection != null) {
connection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return builder.toString();
}
#Override
protected void onPostExecute(String result) {
if (dialog != null) {
dialog.dismiss();
}
Intent intent = new Intent(SEND_RESULT_SEARCH_BROADCAST_FROM_TASK);
intent.putExtra("result_search", result);
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
}
public static class GetPlaceSearchTextTask extends AsyncTask<String , Void , String>{
private String API_TEXT = "https://maps.googleapis.com/maps/api/place/textsearch/" +
"json?query=%1$s&location=[%2$s,%3$s]&radius=5000&key=";
public static final String SEND_BROADCAST_RESULT_TEXT_FROM_TASK = "sand_text_result";
private Context context;
private ProgressDialog dialog ;
public GetPlaceSearchTextTask(Context context){
this.context = context;
}
#Override
protected void onPreExecute() {
if (context != null) {
dialog = new ProgressDialog(context);
dialog.setTitle("Downloading");
dialog.show();
}
}
#Override
protected String doInBackground(String... params) {
HttpsURLConnection connection = null;
BufferedReader reader = null;
StringBuilder builder = new StringBuilder() ;
try {
URL url = new URL(API_TEXT + params[0] + params[1] + params[2]) ;
connection = (HttpsURLConnection) url.openConnection();
if (connection.getResponseCode() != HttpsURLConnection.HTTP_OK){
return null;
}
reader = new BufferedReader(new InputStreamReader(connection.getInputStream())) ;
String line;
while ((line=reader.readLine())!= null){
builder.append(line);
}`enter code here`
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
if (connection!=null)
connection.disconnect();
if (reader!=null)
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
return builder.toString();
}
#Override
protected void onPostExecute(String result_text) {
if (dialog!=null){
dialog.dismiss();
}`enter code here`
Intent intent = new Intent(SEND_BROADCAST_RESULT_TEXT_FROM_TASK);
intent.putExtra("text" , result_text);
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
}
}
}
i need your help. I want to send a URL Request, get response and create a JSON Object. My first try was totally wrong. Now I found a tutorial and made a new try.
My Activity looks like:
public class Patienten extends Activity {
//Beacon Elemente
private String UUID;
private String Major;
private String Minor;
private TextView output;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_patienten);
output = (TextView) findViewById(R.id.output);
UpdateBeaconInformation();
Button cmdHit = (Button) findViewById(R.id.cmd_hit);
cmdHit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
new JSONTask().execute("//http://kusber-web.de/JsonTest.txt");
}
});
setTitle(Surname + ", " + FirstName);
// output.setText(output.getText().toString() + "Gefundener Patient:\n" + "Name: " + Surname + ", " + FirstName + "\nGeb.-Dat: " + Birthdate);
}
Then I created a new Java Class and built an asyncTask with it. But I can't access to the textview output in onPostExecute to update it.
public class JSONTask extends AsyncTask<String, String, String> {
#Override
protected String doInBackground(String... urls) {
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
//http://kusber-web.de/JsonTest.txt
//http://nilsbenning.selfhost.me/PatientFinder.php?beacon_comID=5181f8a3-7354-46ac-b22d-952ec395ab06&beacon_major=12&beacon_minor=249
URL url = new URL(urls[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer buffer = new StringBuffer();
String line;
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
return buffer.toString();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
output.setText(result);
}
}
What is my mistake? Why I can't access to it? I saw it as a solution here but didn't get it to work:
https://stackoverflow.com/a/12252717/5743912
Hope you can help me now! :)
You probably want to fix this (remove leading slashes):
new JSONTask().execute("//http://kusber-web.de/JsonTest.txt");
In your JSONTask you can reference members of Patienten by using Patienten.this. So in onPostExecute you should change this:
output.setText(result);
to:
Patienten.this.output.setText(result);
I am trying to make an app which executes an image search and displays the image results in a grid. Since the Google Image Search API is deprecated and will no longer be available shortly, I am trying to use the Bing Search API.
However, I am getting the following error:
java.io.IOException: No authentication challenges found
at libcore.net.http.HttpURLConnectionImpl.getAuthorizationCredentials(HttpURLConnectionImpl.java:427)
at libcore.net.http.HttpURLConnectionImpl.processAuthHeader(HttpURLConnectionImpl.java:407)
at libcore.net.http.HttpURLConnectionImpl.processResponseHeaders(HttpURLConnectionImpl.java:356)
at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:292)
at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:168)
at libcore.net.http.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:271)
I am following the example in http://learn-it-stuff.blogspot.com/2012/09/using-bing-custom-search-inside-your.html. If anyone has experienced this issue, or can help me out, that would be much appreciated. Thanks!
Here is my code thus far:
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
AsyncTask <Void, Void, Void> task = new AsyncTask <Void, Void, Void> () {
protected Void doInBackground(Void... args) {
// Uri uri = Uri.parse("https://www.google.com/search?tbm=isch&q=penguin");
// Intent intent = new Intent(Intent.ACTION_VIEW, uri);
// startActivity(intent);
/*-------------------------Bing search-------------------------*/
String searchText = "Hello World";
searchText = searchText.replace(" ", "%20");
String accountKey = "MY_APP_ID";
accountKey = accountKey.replace("+", "%2B");
byte[] accountKeyBytes = Base64.encodeBase64((accountKey + ":" + accountKey).getBytes());
String accountKeyEnc = new String(accountKeyBytes);
URL url;
try {
url = new URL(
"https://api.datamarket.azure.com/Bing/Search/v1/"
+ "Image?Query=%27" + searchText + "%27");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "application/json");
conn.setRequestProperty("Authorization", "Basic " + accountKeyEnc);
BufferedReader br = new BufferedReader(new InputStreamReader(
(conn.getInputStream())));
StringBuilder sb = new StringBuilder();
String output;
System.out.println("Output from Server .... \n");
while ((output = br.readLine()) != null) {
sb.append(output);
}
conn.disconnect();
System.out.println(sb);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
};
task.execute();
}
}
The following code worked for me:
public class SearchAsyncTask extends AsyncTask<Void, Void, Void> {
private final String TAG = getClass().getName();
private String mSearchStr;
private int mNumOfResults = 0;
private Callback mCallback;
private BingSearchResults mBingSearchResults;
private Error mError;
public SearchAsyncTask(String searchStr, int numOfResults, Callback callback) {
mSearchStr = searchStr;
mNumOfResults = numOfResults;
mCallback = callback;
}
#Override
protected Void doInBackground(Void... params) {
try {
String searchStr = URLEncoder.encode(mSearchStr);
String numOfResultsStr = mNumOfResults <= 0 ? "" : "&$top=" + mNumOfResults;
String bingUrl = "https://api.datamarket.azure.com/Bing/SearchWeb/v1/Web?Query=%27" + searchStr + "%27" + numOfResultsStr + "&$format=json";
String accountKey = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX";
byte[] accountKeyBytes = Base64.encodeBase64((accountKey + ":" + accountKey).getBytes());
String accountKeyEnc = new String(accountKeyBytes);
URL url = null;
url = new URL(bingUrl);
URLConnection urlConnection = url.openConnection();
urlConnection.setRequestProperty("Authorization", "Basic " + accountKeyEnc);
InputStream response = urlConnection.getInputStream();
String res = readStream(response);
Gson gson = (new GsonBuilder()).create();
mBingSearchResults = gson.fromJson(res, BingSearchResults.class);
Log.d(TAG, res);
//conn.disconnect();
} catch (Exception e) {
e.printStackTrace();
mError = new Error(e.getMessage(), e);
//Log.e(TAG, e.getMessage());
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (mCallback != null) {
mCallback.onComplete(mBingSearchResults, mError);
}
}
private String readStream(InputStream in) {
BufferedReader reader = null;
StringBuilder sb = new StringBuilder();
try {
reader = new BufferedReader(new InputStreamReader(in));
String line = "";
while ((line = reader.readLine()) != null) {
//System.out.println(line);
sb.append(line + "\n");
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return sb.toString();
}
public interface Callback {
void onComplete(Object o, Error error);
}
}
To parse the result:
public class BingSearchResults {
public ResultsContent d;
public static class ResultsContent {
public Result[] results;
public String __next;
}
public static class Result {
public String ID;
public String Title;
public String Description;
public String DisplayUrl;
public String Url;
public Metadata __metadata;
}
public static class Metadata {
public String uri;
public String type;
}
public Result[] getResults(){
if (d == null)
return null;
return d.results;
}
public String getNextUrl(){
if (d == null)
return null;
return d.__next;
}
public boolean isEmpty(){
return (d == null || d.results == null || d.results.length == 0);
}
public int size(){
if (d == null || d.results == null)
return 0;
return d.results.length;
}
}
You also need to include the external jars commons-codec-1.9.jar and gson-2.2.4.jar
Little bit change occur in this code sometimes compilation bug of encoder generate problem byte[] accountKeyBytes = Base64.encodeBase64((accountKey + ":" + accountKey).getBytes());