Here is my java android code which should pass 'Preferred hotels' string to a php file and later read what have been passed.
sendSubMenuDetail("Preferred hotels");
This is evoked at the activity load. Whose function is below:
public void sendSubMenuDetail(String suggestion){
String urlSuffix = "?suggestion="+suggestion;
class RegisterUser extends AsyncTask<String, Void, String> {
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(ActivitySubMenu.this, "Please Wait",null, true, true);
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
loading.dismiss();
Toast.makeText(getBaseContext(),s,Toast.LENGTH_LONG).show();
}
#Override
protected String doInBackground(String... params) {
String s = params[0];
BufferedReader bufferedReader = null;
try {
URL url = new URL(address+s);
HttpURLConnection con = (HttpURLConnection) url.openConnection();
bufferedReader = new BufferedReader(new InputStreamReader(con.getInputStream()));
String result;
result = bufferedReader.readLine();
return result;
}catch(Exception e){
return null;
}
}
}
RegisterUser ru = new RegisterUser();
ru.execute(urlSuffix);
}
The output dislayed in a toast here is 'Preferred' instead of 'Preferred hotels'. I tried figuring out what the problem might be with no success.
Related
Just as a practicing exercise i'm trying to make an app that fetches a JSON from a URL.
I found the following code in other thread here in stackoverflow and it works just fine. My problem is that the URL is hardcoded, and i need it to be an input by the user. What should i change/add?
public class MainActivity extends AppCompatActivity {
Button btnHit;
TextView txtJson;
ProgressDialog pd;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnHit = (Button) findViewById(R.id.btnHit);
txtJson = (TextView) findViewById(R.id.tvJsonItem);
btnHit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
new JsonTask().execute("Url address here");
}
});
}
private class JsonTask extends AsyncTask<String, String, String> {
protected void onPreExecute() {
super.onPreExecute();
pd = new ProgressDialog(MainActivity.this);
pd.setMessage("Please wait");
pd.setCancelable(false);
pd.show();
}
protected String doInBackground(String... params) {
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(params[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+"\n");
Log.d("Response: ", "> " + line); //here u ll get whole response..... :-)
}
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);
if (pd.isShowing()){
pd.dismiss();
}
txtJson.setText(result);
}
}
}
This is the thread where i got that code from:
Get JSON Data from URL Using Android?
Create a constructor in your async Task
private class JSONTask extends AsyncTask<String, String, String> {
String url;
public JSONTask(String url){
this.url=url;
}
use the url string in place of params[0]
And wherever you call your async task do it like this
new JSONTask(textView.getText()).execute()
This should solve it.
Else you can directly use the do in background variable params.
So the problem is that you are using a TextView. TextView does not recieve inputs.
EditText does.
Make these Changes:
TextView txtJson;
In your OnCreate change this:
txtJson = (EditText) findViewById(R.id.tvJsonItem);
btnHit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
new JsonTask().execute(txtJson.getText());
}
});
Now in your xml file change the Button to EditText.
Hope this helps.
If I have this background worker file in my android application and it gets data from my database how can I pass the string 'result' to another class?
The background worker connects to my server and then using php it connects to a database.
public class BackgroundWorker extends AsyncTask<String,Void,String> {
Context context;
AlertDialog alertDialog;
BackgroundWorker (Context ctx) {
context = ctx;
}
#Override
public String doInBackground(String... params) {
String type = params[0];
String specials_url = "";
if(type.equals("venue click")) {
try {
//String user_name = params[1];
URL url = new URL(specials_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"));
// String post_data = URLEncoder.encode("user_name","UTF-8")+"="+URLEncoder.encode(user_name,"UTF-8");
// bufferedWriter.write(post_data);
bufferedWriter.flush();
bufferedWriter.close();
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 (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
#Override
protected void onPreExecute() {
alertDialog = new AlertDialog.Builder(context).create();
alertDialog.setTitle("Info");
}
#Override
protected void onPostExecute(String result) {
alertDialog.setMessage(result);
alertDialog.show();
// String temp = "login success";
// if (result.equals(temp)) {
// Intent intent = new Intent(context, Register.class);
// context.startActivity(intent);
// }
}
#Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
}
You need a listener. This will allow you to notify back when the AsyncTask is done.
Define the listener by creating an interface, like this:
public interface IListener
{
void onCompletedTask(String result);
}
On the task store a reference to the listener.
private IListener mListener;
// Pass the reference to the constructor.
public BackgroundWorker(IListener listener)
{
mListener = listener;
}
Then you notify the listener like this.
#Override
protected void onPostExecute(String result)
{
mListener.onCompletedTask(result);
}
Best way to get a callback from background thread is to use interfaces as a callback from AsyncTask for example:
create an interface that can be called in onPostExecute()
public interface ResponseCallback {
void onRespond(String result);
}
and before calling asynckTask define it like this:
ResponseCallback cpk = new ResponseCallback() {
#Override
public void onRespond(String result) {
//code to be done after calling it from onPostExecute
}
};
and pass cpk to the constructor of of the asynckTask and call it in onPostExecute like that:
if(cpk!=null){
cpk.onRespond(result);
}
of course you can modify the signature of the interface to what ever you want.
I am trying to get information about user by access_token... I have tried a lot of variants for doing this. Although some variants work in the API console but they don't in application.
public class AuthActivity extends AccountAuthenticatorCompatActivity {
private static final String TAG = AuthActivity.class.getSimpleName();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_auth);
Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse(vcs.getAccessRequest()));
startActivity(i);
}
#Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
Uri data = intent.getData();
if(null != data) {
final String accessToken = data.getQueryParameter("code");
AuthTask authTask = new AuthTask(accessToken);
authTask.execute();
}
}
private class AuthTask extends AsyncTask<Void, Void, String> {
private final String mAccessToken;
private final VCS vcs = new Bitbucket();
public AuthTask(final String accessToken) {
mAccessToken = accessToken;
}
#Override
protected String doInBackground(Void... params) {
try {
URL url = new URL("https://api.bitbucket.org/2.0/user");
HttpsURLConnection connection = (HttpsURLConnection)url.openConnection();
connection.addRequestProperty("Authorization", "Bearer " + mAccessToken);
connection.setRequestMethod("GET");
//connection.setRequestProperty("access_token", mAccessToken);
int responseCode = connection.getResponseCode();
BufferedReader in = new BufferedReader(
new InputStreamReader(connection.getInputStream()));
String inputLine;
StringBuilder response = new StringBuilder();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
return response.toString();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String str) {
}
}
}
All requests are work where access token not need. But I cannot use access by token. I really try a lot of ways. Please, post code that will be work. What I do wrong? I don't understand.
So I'm trying to read a message from the server by HttpURLConnection in a AsyncTask class. The problem is, when i send the request to read the data from the server, it just keeps displaying the ProgresssDialog, like it doesn't read the data from the server:
public class MainActivity extends Activity{
EditText name, password;
Button login;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
name = (EditText) findViewById(R.id.name);
password = (EditText) findViewById(R.id.password);
login = (Button) findViewById(R.id.login);
login.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String serverURL = "http://192.168.1.1/my/text.php";
LongOperation longOperation = new LongOperation();
longOperation.execute(serverURL);
}
});
}
private class LongOperation extends AsyncTask<String, Void, Void> {
private String content;
private String error = null;
private ProgressDialog dialog = new ProgressDialog(MainActivity.this);
TextView uiUpdate = (TextView) findViewById(R.id.output);
#Override
protected void onPreExecute() {
uiUpdate.setText("Output : ");
dialog.setMessage("Downloading source..");
dialog.show();
}
#Override
protected Void doInBackground(String... urls) {
try {
URL url = new URL(urls[0]);
HttpURLConnection client = (HttpURLConnection)url.openConnection();
client.connect();
InputStream inputStream = client.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
content = bufferedReader.readLine();
bufferedReader.close();
inputStream.close();
client.disconnect();
} catch (IOException e) {
error = e.getMessage();
}
return null;
}
#Override
protected void onPostExecute(Void unused) {
dialog.dismiss();
if (error != null) {
uiUpdate.setText("Output : "+error);
} else {
uiUpdate.setText("Output : "+content);
}
}
I already tryed before the connectivity to server via HttpClient, so thats not the problem.Thanks!
Try debugging it and see if OnPostExecute() method is getting called or not.!
This seems to get stuck in your stream reader code. Also, add a connection timeout of, say, 5-10 seconds for better user experience.!
Moreover, there seems to be an issue with your return type of doInBackground() method and input parameter type of OnPostExecute() method. As per your AsyncTask definition, they both should be string, isnt it?
See this
Try remove client.connect();
try {
URL url = new URL(urls[0]);
HttpURLConnection client = (HttpURLConnection)url.openConnection();
//remove client.connect();
int response = client.getResponse();
if(response == HttpURLConnection.HTTP_OK){
InputStream inputStream = client.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
content = bufferedReader.readLine();
bufferedReader.close();
inputStream.close();
}
finally{
client.disconnect();
}
} catch (IOException e) {
error = e.getMessage();
}
return null;
Make sure your server is running. Also set request time out.
You are not always required to explicitly call the connect method to initiate the connection. Operations that depend on being connected, like getInputStream, getOutputStream will implicitly perform the connection, when necessary.
This link
Try this:
private class LongOperation extends AsyncTask<String, Void, String>
{
private String content;
private String error = null;
private ProgressDialog dialog = new ProgressDialog(MainActivity.this);
TextView uiUpdate = (TextView) findViewById(R.id.output);
#Override
protected void onPreExecute() {
uiUpdate.setText("Output : ");
dialog.setMessage("Downloading source..");
dialog.show();
}
#Override
protected Strinh doInBackground(String... urls) {
try {
URL url = new URL(urls[0]);
HttpURLConnection client = (HttpURLConnection)url.openConnection(); client.connect();
InputStream inputStream = client.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
content = bufferedReader.readLine();
bufferedReader.close();
inputStream.close();
//client.discon dialog.dismiss();
}
catch (IOException e)
{
content = e.getMessage();
}
return content ;
}
#Override
protected void onPostExecute(String returnValue) {
if (return value != null) {
uiUpdate.setText("Output : "+error);
}
else {
uiUpdate.setText("Output No Value Returned");
}
dialog.dismiss();
}
I'm establishing a server connection, my problem is that I need to put an AsyncTask on my code, because its not working in sdk version 10 up. I don't want to use the StrictMode.ThreadPolicy.
public class TestConnection extends Activity {
#Override
public void onCreate(Bundle cbundle) {
super.onCreate(cbundle);
ConnectivityManager aConnectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo aNetworkInfo = aConnectivityManager.getActiveNetworkInfo();
if (aNetworkInfo != null && aNetworkInfo.isConnected()){
Toast.makeText(this, "Internet Connected", Toast.LENGTH_LONG).show();
}else{
Toast.makeText(this, "Internet Connection Timeout", Toast.LENGTH_LONG).show();
}
URL aURL;
/* Will be filled and displayed later. */
String aString = null;
/* We will show the data we read in a TextView. */
TextView aTextView = new TextView(this);
try {
/* Define the URL we want to load data from. */
aURL = new URL(
"http://url");
/* Open a connection to that URL. */
final HttpURLConnection aHttpURLConnection = (HttpURLConnection) aURL.openConnection();
/* Define InputStreams to read from the URLConnection. */
InputStream aInputStream = aHttpURLConnection.getInputStream();
BufferedInputStream aBufferedInputStream = new BufferedInputStream(
aInputStream);
/* Read bytes to the Buffer until there is nothing more to read(-1) */
ByteArrayBuffer aByteArrayBuffer = new ByteArrayBuffer(50);
int current = 0;
while ((current = aBufferedInputStream.read()) != -1) {
aByteArrayBuffer.append((byte) current);
}
/* Convert the Bytes read to a String. */
aString = new String(aByteArrayBuffer.toByteArray());
} catch (Exception aException) {
/* On any Error we want to display it. */
aString = aException.getMessage();
}
/* Show the String on the GUI. */
aTextView.setText(aString);
this.setContentView(aTextView);
}
}
private class ConnectionTask extends AsyncTask<String, Void, String>{
#Override
protected byte[] doInBackground(String... urls) {
try {
aURL = new URL(
urls[0]);
/* Open a connection to that URL. */
final HttpURLConnection aHttpURLConnection = (HttpURLConnection) aURL.openConnection();
/* Define InputStreams to read from the URLConnection. */
InputStream aInputStream = aHttpURLConnection.getInputStream();
BufferedInputStream aBufferedInputStream = new BufferedInputStream(
aInputStream);
/* Read bytes to the Buffer until there is nothing more to read(-1) */
ByteArrayBuffer aByteArrayBuffer = new ByteArrayBuffer(50);
int current = 0;
while ((current = aBufferedInputStream.read()) != -1) {
aByteArrayBuffer.append((byte) current);
}
/* Convert the Bytes read to a String. */
aString = new String(aByteArrayBuffer.toByteArray()); } catch (IOException e) {
Log.d(TAG, e.toString());
}
return aString;
}
#Override
protected void onPostExecute(String result) {
// result is what you got from your connection
aTextView.setText(result);
}
}
How to call it:
ConnectionTask task = new ConnectionTask();
String[] params = new String[2];
params[0] = url;
params[1] = somethingelseifneeded;
task.execute(params);
In oncreate() u can use like this::
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
StrictMode.ThreadPolicy policy = new
StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
new MyAsynTask().execute(null, null, null);
}
Then in AsynTask do as well::
class MyAsynTask extends AsyncTask<Long, Integer, Integer> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected <Type> doInBackground(Long... params) {
URL ur_url = newURL(http://....)
// do the works on url.....
return <tuped>result;
}
#Override
protected void onPostExecute(Integer result) {
// set the results in Ui
}
}
Refer below code
new FetchRSSFeeds().execute();
private class FetchRSSFeeds extends AsyncTask<String, Void, Boolean> {
private ProgressDialog dialog = new ProgressDialog(HomeActivity.this);
/** progress dialog to show user that the backup is processing. */
/** application context. */
protected void onPreExecute() {
this.dialog.setMessage(getResources().getString(
R.string.Loading_String));
this.dialog.show();
}
protected Boolean doInBackground(final String... args) {
try {
/**
* Write your URL connection code and fetch data here
*/
return true;
} catch (Exception e) {
Log.e("tag", "error", e);
return false;
}
}
#Override
protected void onPostExecute(final Boolean success) {
if (dialog.isShowing()) {
dialog.dismiss();
}
/* Show the String on the GUI. */
aTextView.setText(aString);
this.setContentView(aTextView);
}
}