I recently started learning JSON to use in my apps. I found a weather API (openweathermap.org) and used it on my app. the app runs fine but when I press Button, nothing happens. my source code:
import android.content.Context;
import android.hardware.input.InputManager;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import java.io.*;
import java.net.*;
import java.util.*;
import android.util.*;
import android.view.*;
import android.view.inputmethod.InputMethodManager;
import android.widget.*;
import org.json.*;
public class MainActivity extends AppCompatActivity {
EditText city;
TextView weather, description;
DownloadTask DownloadTask;
public void showWeather (View view)
{
InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(city.getWindowToken(), 0);
try
{
String encodedCityName = URLEncoder.encode(city.getText().toString(), "UTF-8");
DownloadTask = new DownloadTask();
DownloadTask.execute("http://api.openweathermap.org/data/2.5/weather?q=" + encodedCityName + "&appid=812f300ec742971975bbde9a2e0ac0c1");
}
catch (UnsupportedEncodingException e)
{
e.printStackTrace();
Toast.makeText(getApplicationContext(), "Error!", Toast.LENGTH_LONG).show();
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
city = (EditText) findViewById(R.id.city);
weather = (TextView) findViewById(R.id.weather);
description = (TextView) findViewById(R.id.description);
}
public class DownloadTask extends AsyncTask<String, Void, String>
{
#Override
protected String doInBackground(String... urls) {
String result = "";
URL url;
HttpURLConnection connection = null;
try
{
url = new URL(urls[0]);
connection = (HttpURLConnection) url.openConnection();
InputStream in = connection.getInputStream();
InputStreamReader reader = new InputStreamReader(in);
int data = reader.read();
while (data != 1)
{
char current = (char) data;
result += current;
data = reader.read();
}
return result;
}
catch (Exception e)
{
e.printStackTrace();
Toast.makeText(getApplicationContext(), "Error!", Toast.LENGTH_LONG);
}
return null;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
Log.i("Weather content", result);
try
{
JSONObject jsonObject = new JSONObject(result);
String weatherInfo = jsonObject.getString("weather");
Log.i("Weather Content", weatherInfo);
JSONArray jsonArray = new JSONArray(weatherInfo);
String getMain = "";
String getDescription = "";
for (int i = 0; i < jsonArray.length(); i++)
{
JSONObject jsonPart = jsonArray.getJSONObject(i);
getMain = jsonPart.getString("main");
getDescription = jsonPart.getString("description");
Log.i("Main", getMain);
}
if (getMain != "" && getDescription != "")
{
weather.setText(getMain);
description.setText(getDescription);
}
}
catch (JSONException e)
{
e.printStackTrace();
Toast.makeText(getApplicationContext(), "Error!", Toast.LENGTH_LONG);
}
}
}
}
none of Toasts and Logs work.
You have an error in reading the data. You should stop reading when getting -1 not 1.
while (data != -1)
{
char current = (char) data;
result += current;
data = reader.read();
}
Related
I am trying to use android studio to access a streaming/internet API. My API call works in Eclipse without using AsyncTask so I'm trying to use AsyncTask in Android Studio to call the API but I'm not sure why it's not working. The way I use the buffered reader and input stream are the same as the way I used them in eclipse when the call works. I also have permission to use internet in my AndroidManifest.xml.
Note: I took out my API key for obvious reasons.
import android.content.Intent;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.os.AsyncTask;
import android.view.View;
import android.widget.EditText;
import android.view.View.OnClickListener;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener {
private static final String TAG_DEBUG = MainActivity.class.getName();
public static final String TAG_ID = "id";
public static final String TAG_CURRENTTEMP = "currenttemp";
public static final String TAG_MAXTEMP = "maxtemp";
public static final String TAG_MINTEMP = "mintemp";
private EditText enteredzip;
private String zip;
private Button button;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
enteredzip = (EditText) findViewById(R.id.editText);
button = (Button) findViewById(R.id.button);
button.setOnClickListener(this);
}
public void onClick(View v) {
zip = enteredzip.getText().toString();
new RetrieveFeedTask().execute();
}
class RetrieveFeedTask extends AsyncTask<Void, Void, String> {
private Exception exception;
protected void onPreExecute() {
}
protected String doInBackground(Void... urls) {
String BASE_URL = "http://api.openweathermap.org/data/2.5/weather?zip=";
String API_CALL = "&APPID=key";
// Do some validation here
HttpURLConnection con = null;
InputStream is = null;
String bufferedOutput = "";
try {
con = (HttpURLConnection) (new URL(BASE_URL + zip + API_CALL)).openConnection();
con.setRequestMethod("GET");
con.setDoInput(true);
con.setDoOutput(true);
con.connect();
StringBuffer buffer = new StringBuffer();
is = con.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = null;
while((line = br.readLine()) != null)
buffer.append(line + "\r\n");
is.close();
con.disconnect();
bufferedOutput = buffer.toString();
return bufferedOutput;
}
catch(Exception e) {
Log.e("ERROR", e.getMessage(), e);
return null;
} finally {
try{
is.close();
}catch(Throwable T){}
try{
con.disconnect();
}catch(Throwable T){}
}
}
protected void onPostExecute(String response) {
if(response == null) {
//response = "THERE WAS AN ERROR";
//Toast.makeText(MainActivity.this, getResources().getString(R.string.error_et), Toast.LENGTH_LONG).show();
return;
}
//Log.i("INFO", response);
// TODO: check this.exception
// TODO: do something with the feed
Toast.makeText(MainActivity.this, response, Toast.LENGTH_LONG).show();
String id = "";
String currenttemp = "";
String maxtemp = "";
String mintemp = "";
for (int i = 0; i < response.length(); i++) {
if (response.substring(i, i + 2).equals("id")) {
id = response.substring(i + 4, i + 7);
break;
}
}
for (int i = 0; i < response.length(); i++) {
if (response.substring(i, i + 4).equals("temp")) {
currenttemp = response.substring(i + 6, i + 9);
break;
}
}
for (int i = 0; i < response.length(); i++) {
if (response.substring(i, i + 8).equals("temp_min")) {
mintemp = response.substring(i + 10, i + 13);
break;
}
}
for (int i = 0; i < response.length(); i++) {
if (response.substring(i, i + 8).equals("temp_max")) {
maxtemp = response.substring(i + 10, i + 13);
break;
}
}
launchMain2Activity(id, currenttemp, maxtemp, mintemp);
}
}
private void launchMain2Activity(String id, String currenttemp, String maxtemp, String mintemp) {
Intent Main2Activity = new Intent(MainActivity.this, Main2Activity.class);
Main2Activity.putExtra(TAG_ID, id);
Main2Activity.putExtra(TAG_CURRENTTEMP, currenttemp);
Main2Activity.putExtra(TAG_MAXTEMP, maxtemp);
Main2Activity.putExtra(TAG_MINTEMP, mintemp);
startActivity(Main2Activity);
}
try to use this :
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8")) ;
UTF-8 is a method for encoding Unicode characters using 8-bit sequences.
MainActivivity.java
package com.example.anubhav.notesapp;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity2 extends AppCompatActivity {
String url;
EditText et;
TextView t1;
Button btn;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
et = (EditText)findViewById(R.id.editText2);
t1 = (TextView)findViewById(R.id.textView3);
btn = (Button)findViewById(R.id.button);
url = dictionaryEntries();
}
public void requestApiButtonClick(View v)
{
MyDictionaryRequest myDictionaryRequest = new MyDictionaryRequest(this,t1);
myDictionaryRequest.execute(url);
}
private String dictionaryEntries() {
final String language = "en";
final String word = et.getText().toString();
final String word_id = word.toLowerCase();
return "https://od-api.oxforddictionaries.com:443/api/v1/entries/" + language + "/" + word_id;
}
}
DictionaryRequest.java
public class MyDictionaryRequest extends AsyncTask<String,Integer,String> {
final String app_id = "your_apiId";
final String app_key = "Your api_key";
String myurl;
TextView t1;
Context context;
Handler h = new Handler();
MyDictionaryRequest(Context context,TextView t1){
this.context = context;
this.t1=t1;
}
#Override
protected String doInBackground(String... strings) {
myurl = strings[0];
try {
URL url = new URL(myurl);
HttpsURLConnection urlConnection = (HttpsURLConnection) url.openConnection();
urlConnection.setRequestProperty("Accept","application/json");
urlConnection.setRequestProperty("app_id",app_id);
urlConnection.setRequestProperty("app_key",app_key);
// read the output from the server
BufferedReader reader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
StringBuilder stringBuilder = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
stringBuilder.append(line + "\n");
}
return stringBuilder.toString();
}
catch (Exception e) {
e.printStackTrace();
return e.toString();
}
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
String def;
try{
JSONObject js = new JSONObject(s);
JSONArray results = js.getJSONArray("results");
JSONObject lentries = results.getJSONObject(0);
JSONArray lArray= lentries.getJSONArray("lexicalEntries");
JSONObject entries = lArray.getJSONObject(0);
JSONArray e = entries.getJSONArray("entries");
JSONObject senses = e.getJSONObject(0);
JSONArray sensesArray = senses.getJSONArray("senses");
JSONObject d = sensesArray.getJSONObject(0);
JSONArray de = d.getJSONArray("definitions");
def=de.getString(0);
t1.setText(def);
Toast.makeText(context,def,Toast.LENGTH_SHORT).show();
}catch (Exception e)
{
e.printStackTrace();
}
}
}
Everthing is working fine in this code except that I can't get the word's meaning through edit text.
To be more specific :
The code works fine when I add
final String word = "car";
in dictionaryEntries() under Mainactivity.java
but nothing is displayed when :
final String word = et.getText().toString();
you have to move one of your code :
public void requestApiButtonClick(View v) {
MyDictionaryRequest myDictionaryRequest = new MyDictionaryRequest(this, t1);
url = dictionaryEntries();
myDictionaryRequest.execute(url);
}
I am trying to update the data using swipeRefreshLayout, but every time I swipe down to refresh it is only circling but not refreshing.
Can you please help me how to fix it.
package com.reader.ashishyadav271.hackernewsreader;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteStatement;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.widget.SwipeRefreshLayout;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import org.json.JSONArray;
import org.json.JSONObject;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
public class MainActivity extends Activity {
SwipeRefreshLayout mSwipeRefreshLayout;
Map<Integer, String> articleURLs = new HashMap<>();
Map<Integer, String> articleTitles = new HashMap<>();
ArrayList<Integer> articleIds = new ArrayList<>();
SQLiteDatabase articlesDB;
ArrayList<String> titles = new ArrayList<>();
ArrayAdapter arrayAdapter;
ArrayList<String> urls = new ArrayList<>();
ArrayList<String> content = new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSwipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.activity_main_swipe_refresh_layout);
mSwipeRefreshLayout.setColorSchemeResources(R.color.red, R.color.green, R.color.blue, R.color.yellow);
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
refreshContent();
}
});
ListView listView = (ListView) findViewById(R.id.listView);
arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, titles);
listView.setAdapter(arrayAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent i = new Intent(getApplicationContext(), Main2Activity.class);
i.putExtra("articleUrl", urls.get(position));
i.putExtra("content", content.get(position));
startActivity(i);
}
});
articlesDB = this.openOrCreateDatabase("Articles", MODE_PRIVATE, null);
articlesDB.execSQL("CREATE TABLE IF NOT EXISTS articles (id INTEGER PRIMARY KEY, articleId INTEGER, url VARCHAR, title VARCHAR, content VARCHAR)");
updateListView();
DownloadTask task = new DownloadTask();
try {
task.execute("https://hacker-news.firebaseio.com/v0/topstories.json?print=pretty");
} catch (Exception e) {
e.printStackTrace();
}
}
private void refreshContent() {
arrayAdapter.notifyDataSetChanged();
titles.clear();
updateListView();
mSwipeRefreshLayout.setRefreshing(false);
}
public void updateListView() {
try {
Log.i("UI UPDATED", "DONE");
Cursor c = articlesDB.rawQuery("SELECT * FROM articles", null);
int contentIndex = c.getColumnIndex("content");
int urlIndex = c.getColumnIndex("url");
int titleIndex = c.getColumnIndex("title");
c.moveToFirst();
titles.clear();
urls.clear();
while (c != null) {
titles.add(c.getString(titleIndex));
urls.add(c.getString(urlIndex));
content.add(c.getString(contentIndex));
c.moveToNext();
}
arrayAdapter.notifyDataSetChanged();
}catch (Exception e) {
e.printStackTrace();
}
}
public class DownloadTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
String result = "";
URL url;
HttpURLConnection urlConnection;
try {
url = new URL(urls[0]);
urlConnection = (HttpURLConnection) url.openConnection();
InputStream in = urlConnection.getInputStream();
InputStreamReader reader = new InputStreamReader(in);
int data = reader.read();
while (data != -1) {
char current = (char) data;
result += current;
data = reader.read();
}
JSONArray jsonArray = new JSONArray(result);
articlesDB.execSQL("DELETE FROM articles");
for (int i = 0; i < 20; i++) {
String articleId = jsonArray.getString(i);
url = new URL("https://hacker-news.firebaseio.com/v0/item/" + articleId + ".json?print=pretty");
urlConnection = (HttpURLConnection) url.openConnection();
in = urlConnection.getInputStream();
reader = new InputStreamReader(in);
data = reader.read();
String articleInfo = "";
while (data != -1 ) {
char current = (char) data;
articleInfo += current;
data = reader.read();
}
JSONObject jsonObject = new JSONObject(articleInfo);
String articleTitle = jsonObject.getString("title");
String articleURL = jsonObject.getString("url");
String articleContent = "";
/*
url = new URL(articleURL);
urlConnection = (HttpURLConnection) url.openConnection();
in = urlConnection.getInputStream();
reader = new InputStreamReader(in);
data = reader.read();
while (data != -1 ) {
char current = (char) data;
articleInfo += current;
data = reader.read();
}
*/
articleIds.add(Integer.valueOf(articleId));
articleTitles.put(Integer.valueOf(articleId), articleTitle);
articleURLs.put(Integer.valueOf(articleId), articleURL);
String sql = "INSERT INTO articles (articleId, url, title, content) VALUES (? , ? , ? , ?)";
SQLiteStatement statement = articlesDB.compileStatement(sql);
statement.bindString(1, articleId);
statement.bindString(2, articleURL);
statement.bindString(3, articleTitle);
statement.bindString(4, articleContent);
statement.execute();
}
}catch (Exception e) {
e.printStackTrace();
}
return result;
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
refreshContent();
}
}
}
It look like synchronism problem. I can see you load data from DownloadTask and put all of data to database. RefreshMethod query data from database.
I assume if DownloadTask do not finish yet, database isn't updated and RefreshMethod would get nothing from database. So, It is only circling but not refreshing.
To solve synchronism problem, the right application flow should be: Raise PullToRefresh Event -> execute DownloadTask -> Wait until DownloadTask finish, RefreshMethod query database for data.
Code looks like:
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
DownloadTask task = new DownloadTask();
try {
task.execute("https://hacker-news.firebaseio.com/v0/topstories.json?print=pretty");
} catch (Exception e) {
e.printStackTrace();
}
}
});
I have a form having one edittext and an autocompleteview. And a button to search things based on this form. In this form I can either give value in edittext and autocompleteview may be empty and vice versa. On this basis I have passed value of these view to another activity where I made a webservice call and then fetch result.
This is activity where these view are presents:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_patient_section);
getSupportActionBar().hide();
searchByNameEditText = (EditText) findViewById(R.id.searchByNameEditText);
searchByAddressEditText = (EditText) findViewById(R.id.searchByAddressEditText);
searchButton = (Button) findViewById(R.id.searchButton);
autoCompleteTextView = (AutoCompleteTextView) findViewById(R.id.selectStateSpinner);
ArrayAdapter<String> adapter = new ArrayAdapter<>(this,
android.R.layout.simple_dropdown_item_1line,
getResources().getStringArray(R.array.state_arrays));
autoCompleteTextView.setAdapter(adapter);
patientUtilityButton = (Button) findViewById(R.id.patientUtilityButton);
patientUtilityButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
PopupMenu popupMenu = new PopupMenu(PatientSectionActivity.this, patientUtilityButton);
popupMenu.getMenuInflater().inflate(R.menu.patient_utility_button_popmenu, popupMenu.getMenu());
popupMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
#Override
public boolean onMenuItemClick(MenuItem item) {
String patientUtilityMenuItem = item.toString();
patientUtilityButton.setText(patientUtilityMenuItem);
return true;
}
});
popupMenu.show();
}
});
autoCompleteTextView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
selectedStateValue = (String) parent.getItemAtPosition(position);
}
});
doctorName = searchByNameEditText.getText().toString();
// Search Button
searchButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (!selectedStateValue.equals(" ") || doctorName.equals(" ")){
Intent intent = new Intent(PatientSectionActivity.this, DoctorNameActivity.class);
intent.putExtra("State Name", selectedStateValue);
startActivity(intent);
} else if (!doctorName.equals(" ") || selectedStateValue.equals(" ")){
Intent intent = new Intent(PatientSectionActivity.this, DoctorNameActivity.class);
intent.putExtra("Name", doctorName);
startActivity(intent);
}
}
});
}
And in other activity, I get these extras from intent and make webservice call in AsyncTask but my app is crashing. Please any one help me as I am new in android.
This is my other activity
import android.content.Intent;
import android.net.Uri;
import android.os.AsyncTask;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.ProgressBar;
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.net.HttpURLConnection;
import java.net.URL;
public class DoctorNameActivity extends ActionBarActivity {
ArrayAdapter<String> doctorAdapter;
ListView listView;
ProgressBar progressBar;
String doctorName;
String selectedStateValue;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_doctor_name);
progressBar = (ProgressBar) findViewById(R.id.progress);
listView = (ListView) findViewById(R.id.listView);
Intent intent = getIntent();
selectedStateValue = intent.getStringExtra("State Name");
doctorName = intent.getStringExtra("Name");
if (!selectedStateValue.equals(" ") || doctorName.equals(" ")){
FetchDoctorName fetchDoctorName = new FetchDoctorName();
fetchDoctorName.execute(selectedStateValue);
}else if (!doctorName.equals(" ") || selectedStateValue.equals(" ")){
FetchDoctorName fetchDoctorName = new FetchDoctorName();
fetchDoctorName.execute(doctorName);
}
}
private class FetchDoctorName extends AsyncTask<String, Void, String[]>{
private final String LOG_TAG = FetchDoctorName.class.getSimpleName();
public String[] parseDoctorName(String jsonString) throws JSONException{
final String DOCTOR_NAME_ARRAY = "name";
JSONObject object = new JSONObject(jsonString);
JSONArray array = object.getJSONArray(DOCTOR_NAME_ARRAY);
String[] doctorNamesResult = new String[array.length()];
for (int i = 0 ; i < array.length(); i++){
String doctorName = array.getString(i);
Log.v(LOG_TAG, doctorName);
doctorNamesResult[i] = doctorName;
}
return doctorNamesResult;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
progressBar.setVisibility(ProgressBar.VISIBLE);
}
#Override
protected String[] doInBackground(String... params) {
// These two need to be declared outside the try/catch
// so that they can be closed in the finally block.
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
// Will contain the raw JSON response as a string.
String doctorJsonString = null;
try {
final String BASE_URL = "http://mycityortho.com/display_result.php";
final String NAME_PARAM = "name";
final String STATE_PARAM = "state";
URL url = null;
if (params[0].equals(doctorName)){
Uri uri = Uri.parse(BASE_URL).buildUpon()
.appendQueryParameter(NAME_PARAM, params[0])
.build();
url = new URL(uri.toString());
Log.v(LOG_TAG, url.toString());
}else if (params[0].equals(selectedStateValue)){
Uri uri = Uri.parse(BASE_URL).buildUpon()
.appendQueryParameter(STATE_PARAM, params[0])
.build();
url = new URL(uri.toString());
Log.v(LOG_TAG, url.toString());
}
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
doctorJsonString = buffer.toString();
Log.v(LOG_TAG, doctorJsonString);
} catch (IOException e) {
Log.e(LOG_TAG, "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
return null;
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
try {
return parseDoctorName(doctorJsonString);
}catch (JSONException e){
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String[] result) {
progressBar.setVisibility(ProgressBar.GONE);
if (result != null){
doctorAdapter = new ArrayAdapter<>(DoctorNameActivity.this, android.R.layout.simple_list_item_1, result);
listView.setAdapter(doctorAdapter);
}
}
}
As per your code you are sending only one value in intent that is "State Name" or "Name" but in other activity you are trying to receive both value, that why you get null pointer exception.
So use the following code to solve this error.
searchButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (!selectedStateValue.equals(" ") || doctorName.equals(" ")){
Intent intent = new Intent(PatientSectionActivity.this, DoctorNameActivity.class);
intent.putExtra("State Name", selectedStateValue);
intent.putExtra("Name", " ");
startActivity(intent);
} else if (!doctorName.equals(" ") || selectedStateValue.equals(" ")){
Intent intent = new Intent(PatientSectionActivity.this, DoctorNameActivity.class);
intent.putExtra("State Name", " ");
intent.putExtra("Name", doctorName);
startActivity(intent);
}
}
});
package com.example.m2mai;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.sql.Timestamp;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import org.json.JSONArray;
import org.json.JSONObject;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;
public class RetrieveActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_retrieve);
}
public void getStream(View v)
{
new MyAsyncTask().execute();
}
private class MyAsyncTask extends AsyncTask<String, Void, String>
{
ArrayList<String> mNameList = new ArrayList<String>();
public ArrayList<String> atList=new ArrayList<String>();
public ArrayList<String> dataList=new ArrayList<String>();
protected String doInBackground(String... params)
{
return getData();
}
public long getDateTo()
{
EditText toText = (EditText)findViewById(R.id.dateTo);
String To = toText.getText().toString();
DateFormat dateFormatTo = new SimpleDateFormat("dd/MM/yyyy");
Date dateTo = null;
try {
dateTo = dateFormatTo.parse(To);
} catch (java.text.ParseException e) {
.runOnUiThread(new Runnable(){
public void run() {
Toast.makeText(getApplicationContext(),"Please key in the correct input", Toast.LENGTH_LONG).show();
}
});
e.printStackTrace();
}
long timeTo = dateTo.getTime();
new Timestamp(timeTo);
return timeTo/1000;
}
protected String getData()
{
String toTS = ""+getDateTo();
String decodedString="";
String returnMsg="";
String request = "http://api.carriots.com/devices/defaultDevice#eric3231559.eric3231559/streams/?order=-1&max=10&at_to="+toTS;
URL url;
HttpURLConnection connection = null;
try {
url = new URL(request);
connection = (HttpURLConnection) url.openConnection();
connection.addRequestProperty("carriots.apikey", "1234567");
connection.addRequestProperty("Content-Type", "application/json");
connection.setRequestMethod("GET");
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
while ((decodedString = in.readLine()) != null)
{
returnMsg+=decodedString;
}
in.close();
connection.disconnect();
JSONObject nodeRoot = new JSONObject(returnMsg);
JSONArray res = nodeRoot.getJSONArray("result");
for (int i = 0; i < res.length(); i++)
{
JSONObject childJSON = res.getJSONObject(i);
if (childJSON.get("data")!=null)
{
String value = childJSON.getString("data");
dataList.add(value);
JSONObject node=new JSONObject(value);
atList.add(node.get("temperature").toString());
}
}
}
catch (Exception e)
{
e.printStackTrace();
returnMsg=""+e;
}
return returnMsg;
}
protected void onPostExecute(String result)
{
for(int i = 0; i < atList.size(); i++)
{
ListView mainListView = (ListView) findViewById(R.id.listView1);
ArrayAdapter<String> mArrayAdapter = new ArrayAdapter<String>(RetrieveActivity.this,android.R.layout.simple_list_item_1,mNameList);
mainListView.setAdapter(mArrayAdapter);
mNameList.add(atList.get(i).toString());
mArrayAdapter.notifyDataSetChanged();
}
Toast.makeText(getApplicationContext(),result, Toast.LENGTH_SHORT).show();
EditText myData1=(EditText)findViewById(R.id.editText1);
myData1.setText(atList.get(0));
}
}
}
How can I actually display a toast without stoping it? Whenever it falls into the catch it is not responding.
............................................................................................................................................................................................................................................................................
If you are using try-catch in a worker thread and want to display Toast, then I am afraid it is not going to work. You will have to do it in Main(UI) thread.
Try following:
try {
dateTo = dateFormatTo.parse(To);
}
catch (java.text.ParseException e) {
your_activity_context.runOnUiThread(new Runnable(){
public void run() {
Toast.makeText(getApplicationContext(),"Please key in the correct input", Toast.LENGTH_LONG).show();
}
});
e.printStackTrace();
}
Try following:
In getDateTo():
try {
dateTo = dateFormatTo.parse(To);
} catch (java.text.ParseException e) {
runOnUiThread(new Runnable(){
public void run() {
Toast.makeText(getApplicationContext(),"Please key in the correct input", Toast.LENGTH_LONG).show();
}
});
e.printStackTrace();
return -1L; // attention here
}
In getData():
long dateTo = -1L;
if((dateTo = getDateTo()) == -1L){
return null;
}
String toTS = "" + getDateTo();
In onPostExecute:
if(result == null) {
return;
}
Make boolean flag = false; globally.
Inside catch block make flag = true;
Run Toast inside an if block like
if (flag) {
Toast.makeText(this, "Sorry, Couldn't find anything!", Toast.LENGTH_LONG).show();
}
inside your onclick method.