Develop Reference

BufferedReader is not reading the file

I have this code in android studio for an app, I am trying to read from a file for the information of the login but anything after BufferedReader is not executing.
both the registration and login page open, the first page in the app i have sa login button and a registration button, when i click on the login button nothng happen, not even checking if the user exist or not
I tried many ways for reading and writing to a file but I couldn't figure out the error
it is not reading anything and not writing any thing, it simply does nothing.
this is the login page
package com.example.admin.projectfinal;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.TextInputEditText;
import android.support.design.widget.TextInputLayout;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import com.example.admin.projectfinal.val.inputValidation;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.StringTokenizer;
public class LoginActivity extends AppCompatActivity {
private inputValidation InputValidation;
private TextInputLayout IDLayout;
private TextInputLayout PASSWORDlayout;
private TextInputEditText LogID;
private TextInputEditText PASS;
Button SI;
TextView TV;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
getSupportActionBar().hide();
PASS = findViewById(R.id.password);
LogID = findViewById(R.id.idd);
IDLayout = findViewById(R.id.IDLayout);
PASSWORDlayout = findViewById(R.id.PasswordLayout);
TV = findViewById(R.id.tv);
SI = findViewById(R.id.signin);
SI.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
login();
}
});
TV.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Navigate to RegisterActivity
Toast.makeText(LoginActivity.this, "we are in tv.", Toast.LENGTH_LONG).show();
Intent intentRegister = new Intent(LoginActivity.this, RegisterActivity.class);
startActivity(intentRegister);
}
});
InputValidation = new inputValidation(LoginActivity.this);
}
private void login() {
if (!InputValidation.isInputEditTextFilled(LogID, IDLayout, "ID not filled ")) return;
if (!InputValidation.isInputEditTextFilled(PASS, PASSWORDlayout, "Password not filled"))
return;
TextView FileContentTextView = findViewById(R.id.tv_file_content);
try {
File f = new File ("User.txt");
BufferedReader reader = new BufferedReader(new FileReader(f));
if (reader.ready()) {
FileContentTextView.setText("No User registered");
return;
} else {
Toast.makeText(LoginActivity.this, "else", Toast.LENGTH_LONG).show();
boolean found = false;
String role = null;
String line;
while ((line = reader.readLine()) != null) {
Toast.makeText(LoginActivity.this, "while", Toast.LENGTH_LONG).show();
StringTokenizer user = new StringTokenizer(line);
String name = user.nextToken();
String Id = user.nextToken();
String dob = user.nextToken();
String pas = user.nextToken();
String Campus = user.nextToken();
String gender = user.nextToken();
role = user.nextToken();
if (LogID.equals(Id)) {
Toast.makeText(LoginActivity.this, "id is good", Toast.LENGTH_LONG).show();
if (PASS.equals(pas)) {
Toast.makeText(LoginActivity.this, "pass good", Toast.LENGTH_LONG).show();
found = true;
break;
}
}
if (found) {
Toast.makeText(LoginActivity.this, "break.", Toast.LENGTH_LONG).show();
break;
}
}
if (found) {
Toast.makeText(LoginActivity.this, "found", Toast.LENGTH_LONG).show();
if (role.equals("Security")) {
Intent accountsIntent = new Intent(LoginActivity.this, SecurityPage.class);
accountsIntent.putExtra("ID", LogID.getText().toString().trim());
} else {
Intent accountsIntent = new Intent(LoginActivity.this, StudentPage.class);
accountsIntent.putExtra("ID", LogID.getText().toString().trim());
}
} else
reader.close();
}
}catch(IOException e){
e.printStackTrace();
}
}
}
this is the registration code, it has the same problem where anything after the BufferedReader is not executing.
package com.example.admin.projectfinal;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.TextInputEditText;
import android.support.design.widget.TextInputLayout;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.Toast;
import com.example.admin.projectfinal.val.inputValidation;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
public class RegisterActivity extends AppCompatActivity implements View.OnClickListener{
private TextInputLayout textInputLayoutName;
private TextInputLayout textInputLayoutId;
private TextInputLayout textInputLayoutPassword;
private TextInputLayout textInputLayoutDate;
TextInputEditText Name;
TextInputEditText id;
TextInputEditText Password;
TextInputEditText DOB;
Spinner campus;
Spinner Role;
Spinner Gender;
Button btn;
Button Cancel;
private inputValidation InputValidation;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
Name = findViewById(R.id.name);
id = findViewById(R.id.ID);
Password = findViewById(R.id.password);
DOB = findViewById(R.id.dob);
btn = findViewById(R.id.next);
Cancel = findViewById(R.id.cancel);
campus = findViewById(R.id.campus);
Gender = findViewById(R.id.gender);
Role = findViewById(R.id.role);
textInputLayoutName = findViewById(R.id.NameLayout);
textInputLayoutId = findViewById(R.id.IdLayout);
textInputLayoutPassword = findViewById(R.id.PasswordLayout);
textInputLayoutDate = findViewById(R.id.DOBLayout);
//list for campus
String[] CampusList = new String[]{"MainCampus", "SasAlNakhlCampus", "MasdarCampus"};
ArrayAdapter<String> adapter1 = new ArrayAdapter<>(this, android.R.layout.simple_spinner_dropdown_item, CampusList);
campus.setAdapter(adapter1);
//list for gender
String[] gen = new String[]{"Male", "Female"};
ArrayAdapter<String> genAdapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_dropdown_item, gen);
Gender.setAdapter(genAdapter);
//list for role
String[] rolee = new String[]{"Student", "Security"};
ArrayAdapter<String> roleAdapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_dropdown_item, rolee);
Role.setAdapter(roleAdapter);
// Buttons validation
btn.setOnClickListener(this);
Cancel.setOnClickListener(this);
InputValidation = new inputValidation(RegisterActivity.this);
}
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.next:
try {
validate();
} catch (IOException e) {
Log.e("Exception", "File write failed: " + e.toString());
}
break;
case R.id.cancel:
// Navigate to RegisterActivity
Intent intentRegister = new Intent(this, LoginActivity.class);
startActivity(intentRegister);
break;
}
}
private void validate() throws IOException {
boolean filled = true;
if (!InputValidation.isInputEditTextFilled(Name, textInputLayoutName, "Fill Name")) {
filled = false;
return;
}
if (!InputValidation.isInputEditTextFilled(id, textInputLayoutId, "Fill ID")) {
filled = false;
return;
}
if (!InputValidation.isInputEditTextFilled(DOB, textInputLayoutDate, "Fill Date")) {
filled = false;
return;
}
if (!InputValidation.isInputEditTextFilled(Password, textInputLayoutPassword, "Invalid Password")) {
filled = false;
return;
}
if (filled){
//if (!UserInfo.exists()) UserInfo.createNewFile();
String line;
boolean found = false;
BufferedReader reader= new BufferedReader(new FileReader("User.txt"));
Toast.makeText(getBaseContext(), "ready", Toast.LENGTH_LONG).show();
while ((line = reader.readLine()) != null) {
Toast.makeText(getBaseContext(), "while", Toast.LENGTH_LONG).show();
String[] user = line.split(" ");
String name = user[0];
String Id = user[1];
String dob = user[2];
String password = user[3];
String Campus = user[4];
String gender = user[5];
String role = user[6];
if (id.equals(Id)) {
found = true;
Toast.makeText(getBaseContext(), "User Exist", Toast.LENGTH_LONG).show();
break;
}
if (!found) {
// Adds a line to the file
PrintWriter writer = new PrintWriter(new BufferedWriter(new FileWriter("User.txt")));
writer.append(Name + " " + id + " " + DOB + " " + Password + " "
+ campus.getSelectedItem() + " " + Gender.getSelectedItem() + " " + Role.getSelectedItem() + "/n" );
}
}
reader.close();
}
}
}
Input validation class I used in the code:
package com.example.admin.projectfinal.val;
import android.app.Activity;
import android.content.Context;
import android.support.design.widget.TextInputEditText;
import android.support.design.widget.TextInputLayout;
import android.view.View;
import android.view.WindowManager;
import android.view.inputmethod.InputMethodManager;
public class inputValidation {
private static Context context;
/**
* constructor
*
* #param context
*/
public inputValidation(Context context) {
this.context = context;
}
/**
* method to check InputEditText filled .
*
* #param textInputEditText
* #param textInputLayout
* #param message
* #return
*/
public static boolean isInputEditTextFilled(TextInputEditText textInputEditText, TextInputLayout textInputLayout, String message) {
String value = textInputEditText.getText().toString().trim();
if (value.isEmpty()) {
textInputLayout.setError(message);
hideKeyboardFrom(textInputEditText);
return false;
} else {
textInputLayout.setErrorEnabled(false);
}
return true;
}
/**
* method to Hide keyboard
*
* #param view
*/
private static void hideKeyboardFrom(View view) {
InputMethodManager imm = (InputMethodManager) context.getSystemService(Activity.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(view.getWindowToken(), WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
}
}

Check box sending value to next activity even after deselcting it

I used a listview to display the check boxes in my activity. I also put a check to see atleast one check box is checked otherwise it will toast a message asking the user to please select atleast one value. Below are my two classes. Problem which i am having is that when i press the submit button without selecting a check box then i get a message to select atleast one checkbox. But when i select and deselect the check box and then submit it then it goes to the next activity with value of the check box which i dont want. It should not go to the other activity till i select one checkbox. Please help me with this problem.
ConnectAdapter.java
package com.arcadian.adapter;
import java.util.ArrayList;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.Toast;
import android.widget.CompoundButton.OnCheckedChangeListener;
import com.arcadian.genconian.R;
public class ConnectAdapter extends ArrayAdapter<ConnectModel> {
public ArrayList<ConnectModel> stateList;
Context cntx;
public static ConnectModel connect;
CheckBox cb;
public ConnectAdapter(Context context, int textViewResourceId,
ArrayList<ConnectModel> stateList) {
super(context, textViewResourceId, stateList);
this.cntx = context;
this.stateList = new ArrayList<ConnectModel>();
this.stateList.addAll(stateList);
}
public class ViewHolder {
CheckBox connect_CB;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
Log.v("ConvertView", String.valueOf(position));
if (convertView == null) {
LayoutInflater vi = (LayoutInflater) cntx
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = vi.inflate(R.layout.list_connect_row, null);
holder = new ViewHolder();
holder.connect_CB = (CheckBox) convertView
.findViewById(R.id.connect_CB);
convertView.setTag(holder);
holder.connect_CB
.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton v,
boolean isChecked) {
// TODO Auto-generated method stub
cb = (CheckBox) v;
if (v.isChecked()) {
connect = (ConnectModel) cb.getTag();
/*
* Toast.makeText( cntx.getApplicationContext(),
* "Checkbox: " + cb.getText() + " -> " +
* cb.isChecked(), Toast.LENGTH_LONG).show();
*/
connect.setSelected(cb.isChecked());
}
// else{
// Toast.makeText(getContext(), "Select aleast one.", Toast.LENGTH_LONG).show();
// String select = null;
// }
}
});
}
else {
holder = (ViewHolder) convertView.getTag();
}
ConnectModel state = stateList.get(position);
holder.connect_CB.setText(state.getName());
holder.connect_CB.setChecked(state.isSelected());
holder.connect_CB.setTag(state);
return convertView;
}
}
**ConnectActivity.java**
package com.arcadian.genconian;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;
import com.arcadian.adapter.ConnectAdapter;
import com.arcadian.adapter.ConnectModel;
import com.arcadian.utils.CommonActivity;
import com.arcadian.utils.Constants;
import com.arcadian.utils.JSONParser;
public class ConnectActivity extends CommonActivity implements OnClickListener {
ConnectAdapter dataAdapter = null;
ArrayList<ConnectModel> stateList;
private ProgressDialog pDialog;
String to_connect;
String response;
private StringBuffer responseText;
int success;
String email, type;
private String status;
String select;
ConnectModel _ConnectModel;
ConnectModel selstate;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_connect);
// Generate list View from ArrayList
displayListView();
responseText = new StringBuffer();
Button submit_BT = (Button) findViewById(R.id.submit_BT);
submit_BT.setOnClickListener(this);
Intent i = getIntent();
email = i.getStringExtra("user_email");
type = i.getStringExtra("type");
}
private void displayListView() {
// Array list of countries
stateList = new ArrayList<ConnectModel>();
_ConnectModel = new ConnectModel("All", false);
stateList.add(_ConnectModel);
_ConnectModel = new ConnectModel("Stream", false);
stateList.add(_ConnectModel);
_ConnectModel = new ConnectModel("Industry", false);
stateList.add(_ConnectModel);
_ConnectModel = new ConnectModel("Field", false);
stateList.add(_ConnectModel);
_ConnectModel = new ConnectModel("Batchmates", false);
stateList.add(_ConnectModel);
// create an ArrayAdaptar from the String Array
dataAdapter = new ConnectAdapter(this, android.R.layout.simple_list_item_multiple_choice,
stateList);
ListView to_connect_LV = (ListView) findViewById(R.id.to_connect_LV);
// Assign adapter to ListView
to_connect_LV.setAdapter(dataAdapter);
}
#Override
public void onClick(View v) {
int id = v.getId();
// openRequest.setCallback(statusCallback);
// session.openForRead(openRequest);
// loginProgress.setVisibility(View.VISIBLE);
switch (id) {
case R.id.submit_BT:
ArrayList<ConnectModel> stateList = dataAdapter.stateList;
response = "";
for (int i = 0; i < stateList.size(); i++) {
ConnectModel state = stateList.get(i);
selstate = ConnectAdapter.connect;
if(selstate!=null)
if (selstate.equals(state)) {
select = "abc";
if ((stateList.size() - 1) >= i) {
responseText.append(state.getName() + ",");
String text = state.getName();
response = responseText.toString();
loge("response", "response text is" + responseText);
}
else {
responseText.append(state.getName());
}
}
}
if (select == null) {
Toast.makeText(getApplicationContext(), "Select at least one.",
Toast.LENGTH_SHORT).show();
} else {
new Connect().execute();
}
/*
* if(response.length()>1) {
* if(response.substring(response.length()-1).equals(",") ) {
* response
* =response.replace(response.substring(response.length()-1), "" );
*
* }
*
* }
*
* if (response.length() <= 1) { response =
* "batch,stream,field,industry"; }
*/
break;
default:
break;
}
}
public class Connect extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(ConnectActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#Override
protected String doInBackground(String... params) {
to_connect = responseText.toString();
String connect_url = Constants.REMOTE_URL + "/GenconianApi/reg2";
log("to", "connect url is:" + connect_url);
try {
JSONParser jsonParser = new JSONParser();
List<NameValuePair> Params = new ArrayList<NameValuePair>();
String res;
Intent email_Intent = getIntent();
email = email_Intent.getStringExtra("user_email");
type = email_Intent.getStringExtra("type");
loge("email in", "connectactivity is:" + email);
int len = response.length();
StringBuilder builder = new StringBuilder();
for (int i = 0; i < len - 1; i++) {
builder.append(Character.toLowerCase(response.charAt(i)));
}
Params.add(new BasicNameValuePair("email", email));
Params.add(new BasicNameValuePair("connected", builder
.toString()));
Log.e("responce", builder.toString());
JSONObject json = jsonParser.makeHttpRequest(connect_url,
"POST", Params);
loge("in reg2", json.toString());
JSONObject obj = json.getJSONObject("Status");
loge("obj is", obj.toString());
status = obj.getString("status");
loge("user", "status is:" + status);
success = Integer.parseInt(status);
loge("chk", "rslt code is:" + success);
if (success == 1) {
Intent k = new Intent(ConnectActivity.this,
FindFriends.class);
loge("chk", "inside success:" + success);
k.putExtra("user_email", email);
k.putExtra("type", type);
overridePendingTransition(R.anim.slide_in, R.anim.slide_out);
startActivity(k);
loge("email", "" + email);
return json.getString(Constants.TAG_MESSAGE);
} else {
Log.e("Login Failure!",
json.getString(Constants.TAG_MESSAGE));
return json.getString(Constants.TAG_MESSAGE);
}
}
catch (JSONException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
pDialog.dismiss();
}
}
#Override
public void onBackPressed() {
// TODO Auto-generated method stub
super.onBackPressed();
Intent i = new Intent(ConnectActivity.this, More.class);
i.putExtra("user-email", email);
i.putExtra("type", type);
startActivity(i);
}
}

You can put all the checkboxes in a Collection of checkboxes.
Upon clicking submit button, loop through all checkboxes to see anyone of them is checked at that moment
Collection<CheckBox> boxes=new Vector<CheckBox>();
...
public void onClick(View v){
boolean anyoneChecked=false;
for(CheckBox b: boxes){
if(b.isChecked()){
anyoneChecked=true;
}
}
if(!anyoneChecked){
return;
}
// go to next activity
}

How do I post and retrieve tweets in an Android app?

I'm trying to make a Twitter app which includes posting and retrieving tweets from the user's timeline and setting it in a list view which also updates when someone tweets.
I also wish to allow the user to upload photos to Twitter.
Here's my code:
package com.example.listtweetdemo;
import java.util.ArrayList;
import java.util.List;
import twitter4j.Paging;
import twitter4j.ResponseList;
import twitter4j.Status;
import twitter4j.Twitter;
import twitter4j.TwitterException;
import twitter4j.TwitterFactory;
import twitter4j.User;
import twitter4j.auth.AccessToken;
import twitter4j.auth.RequestToken;
import twitter4j.conf.Configuration;
import twitter4j.conf.ConfigurationBuilder;
import twitter4j.internal.org.json.JSONArray;
import twitter4j.internal.org.json.JSONObject;
import twitter4j.json.DataObjectFactory;
import android.app.Activity;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.widget.SimpleCursorAdapter;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends ListActivity {
private Button twitt;
private Button read;
private Button login;
private Button logout;
private EditText edt;
private boolean man = true;
private TextView textName;
private ListView list;
List<Status> statuses = new ArrayList<Status>();
static final String consumerKey = "RVVVPnAUa8e1XXXXXXXXX";
static final String consumerSecretKey = "eCh0Bb12n9oDmcomBdfisKZIfJmChC2XXXXXXXXXXXX";
static final String prefName = "twitter_oauth";
static final String prefKeyOauthToken = "oauth_token";
static final String prefKeyOauthSecret = "oauth_token_secret";
static final String prefKeyTwitterLogin = "isTwitterLogedIn";
static final String twitterCallbackUrl = "oauth://t4jsample";
static final String urlTwitterOauth = "auth_url";
static final String urlTwitterVerify = "oauth_verifier";
static final String urlTwitterToken = "oauth_token";
static SharedPreferences pref;
private static Twitter twitter;
private static RequestToken reqToken;
private connectionDetector cd;
AlertDailogManager alert = new AlertDailogManager();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setUpIds();
cd = new connectionDetector(getApplicationContext());
if(!cd.isConnectivityToInternet())
{
alert.showAlert(MainActivity.this, "Internet Connection Error", "Please Connect to working Internet connection", false);
return;
}
if(consumerKey.trim().length() == 0 || consumerSecretKey.trim().length() == 0)
{
alert.showAlert(MainActivity.this, "Twitter Oauth Token", "Please set your Twitter oauth token first!", false);
return;
}
login.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
loginToTwitter();
}
});
logout.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
logoutFromTwitter();
}
});
read.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//Paging paging = new Paging(200); // MAX 200 IN ONE CALL. SET YOUR OWN NUMBER <= 200
try {
statuses = twitter.getHomeTimeline();
} catch (TwitterException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
String strInitialDataSet = DataObjectFactory.getRawJSON(statuses);
JSONArray JATweets = new JSONArray(strInitialDataSet);
for (int i = 0; i < JATweets.length(); i++) {
JSONObject JOTweets = JATweets.getJSONObject(i);
Log.e("TWEETS", JOTweets.toString());
}
} catch (Exception e) {
// TODO: handle exception
}
/*try {
ResponseList<Status> statii = twitter.getHomeTimeline();
statusListAdapter adapter = new statusListAdapter(getApplicationContext(), statii);
setListAdapter(adapter);
Log.d("HOME TIMELINE", statii.toString());
} catch (TwitterException e) {
e.printStackTrace();
}
//list.setVisibility(View.VISIBLE);
read.setVisibility(View.GONE);*/
}
});
twitt.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String status = edt.getText().toString();
if(status.trim().length() > 0)
{
new updateTwitter().execute(status);
}
}
});
if(!isTwitterLogedInAlready())
{
Uri uri = getIntent().getData();
if(uri != null && uri.toString().startsWith(twitterCallbackUrl))
{
String verify = uri.getQueryParameter(urlTwitterVerify);
try
{
AccessToken accessToken = twitter.getOAuthAccessToken(reqToken,verify);
Editor edit = pref.edit();
edit.putString(prefKeyOauthToken, accessToken.getToken());
edit.putString(prefKeyOauthSecret, accessToken.getTokenSecret());
edit.putBoolean(prefKeyTwitterLogin, true);
edit.commit();
Log.d("Twitter oauth Token", ">" + accessToken.getToken());
login.setVisibility(View.INVISIBLE);
twitt.setVisibility(View.VISIBLE);
edt.setVisibility(View.VISIBLE);
read.setVisibility(View.VISIBLE);
textName.setVisibility(View.VISIBLE);
if(man == true)
{
logout.setVisibility(View.VISIBLE);
}
long userId = accessToken.getUserId();
User user = twitter.showUser(userId);
//User user = twitter.getHomeTimeline();
Status n = user.getStatus();
String userName = user.getName();
textName.setText(userName);
}
catch(Exception e)
{
Log.d("Twitter Login Error", ">" + e.getMessage());
}
}
}
}
private void setUpIds() {
twitt = (Button)findViewById(R.id.buttTwitt);
login = (Button)findViewById(R.id.buttLogin);
read = (Button)findViewById(R.id.buttRead);
edt = (EditText)findViewById(R.id.editText1);
logout = (Button)findViewById(R.id.buttLogout);
textName = (TextView)findViewById(R.id.textName);
//list = (ListView)findViewById(R.id.listView1);
pref = getApplicationContext().getSharedPreferences("myPref", 0);
}
protected void logoutFromTwitter() {
Editor e = pref.edit();
e.remove(prefKeyOauthSecret);
e.remove(prefKeyOauthToken);
e.remove(prefKeyTwitterLogin);
e.commit();
login.setVisibility(View.VISIBLE);
logout.setVisibility(View.GONE);
twitt.setVisibility(View.GONE);
edt.setVisibility(View.GONE);
read.setVisibility(View.GONE);
textName.setVisibility(View.GONE);
}
protected void loginToTwitter() {
if(!isTwitterLogedInAlready())
{
ConfigurationBuilder builder = new ConfigurationBuilder();
builder.setOAuthConsumerKey(consumerKey);
builder.setOAuthConsumerSecret(consumerSecretKey);
builder.setJSONStoreEnabled(true);
builder.setIncludeEntitiesEnabled(true);
builder.setIncludeMyRetweetEnabled(true);
builder.setIncludeRTsEnabled(true);
Configuration config = builder.build();
TwitterFactory factory = new TwitterFactory(config);
twitter = factory.getInstance();
try{
reqToken = twitter.getOAuthRequestToken(twitterCallbackUrl);
this.startActivity(new Intent(Intent.ACTION_VIEW,
Uri.parse(reqToken.getAuthenticationURL())));
}
catch(TwitterException e)
{
e.printStackTrace();
}
}
else
{
Toast.makeText(getApplicationContext(), "Already Logged In", Toast.LENGTH_LONG).show();
logout.setVisibility(View.VISIBLE);
man = false;
}
}
private boolean isTwitterLogedInAlready() {
return pref.getBoolean(prefKeyTwitterLogin, false);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public class updateTwitter extends AsyncTask<String , String, String>{
private ProgressDialog pDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Updating to Twitter status..");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
#Override
protected String doInBackground(String... args) {
Log.d("Tweet Text", "> " + args[0]);
String status = args[0];
try {
ConfigurationBuilder builder = new ConfigurationBuilder();
builder.setOAuthConsumerKey(consumerKey);
builder.setOAuthConsumerSecret(consumerSecretKey);
// Access Token
String access_token = pref.getString(prefKeyOauthToken, "");
// Access Token Secret
String access_token_secret = pref.getString(prefKeyOauthSecret, "");
AccessToken accessToken = new AccessToken(access_token, access_token_secret);
Twitter twitter = new TwitterFactory(builder.build()).getInstance(accessToken);
// Update status
twitter4j.Status response = twitter.updateStatus(status);
Log.d("Status", "> " + response.getText());
} catch (TwitterException e) {
// Error in updating status
Log.d("Twitter Update Error", e.getMessage());
}
return null;
}
#Override
protected void onPostExecute(String result) {
pDialog.dismiss();
runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(getApplicationContext(), "Status update successfully", Toast.LENGTH_SHORT).show();
edt.setText("");
}
});
}
}
}

Use the new Twitter Fabric SDK for Android. Requires sign up first. If you don't want to wait to be approved for the sign up, then I recommend using the following link
https://github.com/Rockncoder/TwitterTutorial
The link above explains how to retrieve tweets. You should be able to use the above link COMBINED with the information in the link below to POST tweets!
https://dev.twitter.com/overview/documentation

want to interrupt a thread but thread is null

I want to interrupt a thread1 from another thread2 but when I try make the thread1.interrupt(); call I get a null pointer error.
I'm making an android app, I'm on an android login page and when I login I create and start a thread called sessionTimer (which does a session countdown say 2min). What I want is that when I press logout in a different activity that I go to the login page and my sessionTimer thread should be interrupted so that I can start a new login session with max time.
package com.AndroidApp.Login;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.AndroidApp.R;
import com.AndroidApp.domain.Utente;
import com.AndroidApp.pagine.MenuPagina;
public class LoginActivity extends Activity {
final String TAG = "LogIN";
ArrayList<HashMap<String, String>> mylist;
private Button bLogin, bExit;
private EditText utente, passwd;
private MediaPlayer mpButtonClick = null;
private SharedPreferences mPreferences;
public volatile Thread sessionTimer;
public long tId = -1;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.login);
mPreferences = getSharedPreferences("CurrentUser", MODE_PRIVATE);
SharedPreferences.Editor editor = mPreferences.edit();
editor.clear();
editor.commit();
String nome = mPreferences.getString("nome", "Nessuno");
setTitle("Sessione di : " + nome);
Log.w("TotThreads", Integer.toString(Thread.activeCount()));
/*
final SessionTimer st = new SessionTimer();
*/
if(MenuPagina.reset){
Log.w("sessionTimer ID", Long.toString(sessionTimer.getId()));
if (sessionTimer == null)
Log.w("sessionTimer", "sessionTimer is NULL");
sessionTimer.interrupt();
System.out.println("end current session");
//st.stopRequest();
}
if (!checkLoginInfo()) {
mpButtonClick = MediaPlayer.create(this, R.raw.button);
bLogin = (Button)findViewById(R.id.bLogin);
bLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
mpButtonClick.start();
Log.v(TAG, "Trying to Login");
utente = (EditText)findViewById(R.id.etUtente);
passwd = (EditText)findViewById(R.id.etPassword);
String username = utente.getText().toString();
username = ("ccce#eex.it");
String password = md5(passwd.getText().toString());
password = md5("12345");
XMLFunctionsLogin.getInstance().setNewURL("u=" + username + "&p=" + password);
String xml = XMLFunctionsLogin.getXML();
Document doc = XMLFunctionsLogin.xmlFromString(xml);
int status = XMLFunctionsLogin.errStatus(doc);
Log.v("status", Integer.toString(status));
if ((status == 0)) {
NodeList nodes = doc.getElementsByTagName("login");
Element e = (Element) nodes.item(0);
Utente utente = new Utente();
utente.setIdUtente(XMLFunctionsLogin.getValue(e, "idUtente"));
utente.setNome(XMLFunctionsLogin.getValue(e, "nome"));
utente.setCognome(XMLFunctionsLogin.getValue(e, "cognome"));
Log.v("utente", utente.getCognome().toString());
List<NameValuePair> nvps = new ArrayList<NameValuePair>(2);
nvps.add(new BasicNameValuePair("utente", username));
nvps.add(new BasicNameValuePair("password", password));
Log.v(TAG, nvps.get(0).toString());
Log.v(TAG, nvps.get(1).toString());
// Store the username and password in SharedPreferences after the successful login
SharedPreferences.Editor editor = mPreferences.edit();
editor.putString("userName", username);
editor.putString("password", password);
editor.putString("idUtente", utente.getIdUtente());
editor.putString("nome", utente.getNome());
editor.putString("cognome", utente.getCognome());
editor.commit();
Log.v(TAG, "timer");
Log.v("RESET", Boolean.toString(MenuPagina.reset));
/*
Thread t = new Thread(st);
t.start();
*/
sessionTimer = new Thread() {
#Override
public void run() {
long tId = Thread.currentThread().getId();
Log.w("TTthread Id", Long.toString(tId));
for (int i = 30; i >= 0; i -= 1) {
if ((i == 0) || (MenuPagina.reset)) {
System.out.print("timer finito");
Log.i("Timer", "timer finito");
LoginActivity.this.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(LoginActivity.this, "ti si è scaduta la sessione", Toast.LENGTH_LONG).show();
}
});
Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
//System.exit(0);
} try {
Thread.sleep(1000);
Log.i("Timer", Integer.toString(i));
} catch (InterruptedException e) {
Log.i("Catch", "Catchhhhhhhhhhhh");
e.printStackTrace();
Thread.currentThread().interrupt();
return;
}
}
}
};
sessionTimer.start();
Log.v(TAG, "Successo2");
Toast.makeText(LoginActivity.this, "LogIn con successo", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(getApplicationContext()/*LoginActivity.this*/, MenuPagina.class);
startActivity(intent);
} else {
final String errorMessage = XMLFunctionsLogin.errStatusDesc(doc);
Log.v("fallimento", errorMessage);
LoginActivity.this.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(LoginActivity.this, errorMessage, Toast.LENGTH_LONG).show();
}
});
Intent intent = getIntent();
finish();
startActivity(intent);
}
}
});
bExit = (Button)findViewById(R.id.bExit);
bExit.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
mpButtonClick.start();
finish();
}
});
}
}
//Checking whether the username and password has stored already or not
private final boolean checkLoginInfo() {
boolean username_set = mPreferences.contains("UserName");
boolean password_set = mPreferences.contains("PassWord");
if ( username_set || password_set ) {
return true;
}
return false;
}
//md5 for crypting and hash
private static String md5(String data) {
byte[] bdata = new byte[data.length()];
int i;
byte[] hash;
for (i = 0; i < data.length(); i++)
bdata[i] = (byte) (data.charAt(i) & 0xff);
try {
MessageDigest md5er = MessageDigest.getInstance("MD5");
hash = md5er.digest(bdata);
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
StringBuffer r = new StringBuffer(32);
for (i = 0; i < hash.length; i++) {
String x = Integer.toHexString(hash[i] & 0xff);
if (x.length() < 2)
r.append("0");
r.append(x);
}
return r.toString();
}
}
So what happens is when I logout and I come back to the login page and MenuPagina.reset = true I get an error saying that sessionTimer is null. Why?
I've tried also using a seperate class for the thread but I get the same null pointer error.

onCreate runs when your Activity is being created or re-created, either way it's a new object, so any local variables have to be initialized again, in your case sessionTimer would be null until the new Thread() {} call.
If you need to persist a reference to your thread, use more global object than your Activity is - Application, that's a base class for maintaining global application state. You can always access it by calling Context.getApplicationContext(). Anyway, read the docs.

AsyncTask is not working properly in android 4.0

I have this async Task on android 2.3.5
class InternetConnexionErrorAsync extends AsyncTask<String, String, String>
{
#Override
protected void onPreExecute() {
super.onPreExecute();
mdpiImageView.setClickable(false);
journalsImageView.setClickable(false);
accountImageView.setClickable(false);
Toast.makeText(getBaseContext(),errorMessage , Toast.LENGTH_LONG).show();
}
#Override
protected String doInBackground(String... aurl) {
try {
Thread.sleep(3450);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String unused)
{
finish();
}
}
Everything is working well.
When I try this in Android 4.0, I am newer accessint the onPostExecute.
Could you please help me. No error message, only that the onPostExecute is newer reached.

Whatever you need to update on the UI you need to do in onPostExecute.
The code below, take a look at onPostExecute - specifically the activity.xx() methods send updates to the main activity that do things on the UI.
For example:
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import library.DatabaseHandler;
import library.JSONParser;
import library.UserFunctions;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import com.actionbarsherlock.R;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class LoginTask extends AsyncTask<String, Void, Integer> {
private ProgressDialog progressDialog;
private Polling activity;
private int id = -1;
private JSONParser jsonParser;
private static String loginURL = "http://davidjkelley.net/android_api/";
private static String registerURL = "http://davidjkelley.net/android_api/";
private static String KEY_SUCCESS = "success";
private static String KEY_ERROR = "error";
private static String KEY_ERROR_MSG = "error_msg";
private static String KEY_UID = "uid";
private static String KEY_NAME = "name";
private static String KEY_EMAIL = "email";
private static String KEY_CREATED_AT = "created_at";
private int responseCode = 0;
public LoginTask(Polling activity, ProgressDialog progressDialog)
{
this.activity = activity;
this.progressDialog = progressDialog;
}
#Override
protected void onPreExecute()
{
progressDialog.show();
}
protected Integer doInBackground(String... arg0) {
EditText userName = (EditText)activity.findViewById(R.id.emailEditText);
EditText passwordEdit = (EditText)activity.findViewById(R.id.passEditText);
String email = userName.getText().toString();
String password = passwordEdit.getText().toString();
UserFunctions userFunction = new UserFunctions();
JSONObject json = userFunction.loginUser(email, password);
// check for login response
try {
if (json.getString(KEY_SUCCESS) != null) {
String res = json.getString(KEY_SUCCESS);
if(Integer.parseInt(res) == 1){
//user successfully logged in
// Store user details in SQLite Database
DatabaseHandler db = new DatabaseHandler(activity.getApplicationContext());
JSONObject json_user = json.getJSONObject("user");
//Log.v("name", json_user.getString(KEY_NAME));
// Clear all previous data in database
userFunction.logoutUser(activity.getApplicationContext());
db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL),
json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT));
responseCode = 1;
// Close Login Screen
//finish();
}else{
responseCode = 0;
// Error in login
}
}
} catch (NullPointerException e) {
e.printStackTrace();
}
catch (JSONException e) {
e.printStackTrace();
}
return responseCode;
}
#Override
protected void onPostExecute(Integer responseCode)
{
EditText userName = (EditText)activity.findViewById(R.id.emailEditText);
EditText passwordEdit = (EditText)activity.findViewById(R.id.passEditText);
if (responseCode == 1) {
progressDialog.dismiss();
activity.loginReport(responseCode);
userName.setText("");
passwordEdit.setText("");
//shared prefences, store name
}
if (responseCode == 0) {
progressDialog.dismiss();
activity.loginReport(responseCode);
}
//if(responseCode == 202)
//activity.login(id);
//else
//activity.showLoginError("");
}
}
Here's the main activity, you can see what loginReport does:
public class Polling extends SherlockFragmentActivity {
private ViewPager mViewPager;
private TabsAdapter mTabsAdapter;
private final static String TAG = "21st Polling:";
private Button loginButton;
private Button registerButton;
private CheckBox remember;
SharedPreferences sharedPreferences;
Toast toast;
ActionBar bar;
//DatabaseHandler ;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.v(TAG, "onCreate");
mViewPager = new ViewPager(this);
mViewPager.setId(R.id.pager);
setContentView(mViewPager);
bar = getSupportActionBar();
bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
bar.setDisplayShowTitleEnabled(false);
bar.setDisplayShowHomeEnabled(false);
mTabsAdapter = new TabsAdapter(this, mViewPager);
mTabsAdapter.addTab(bar.newTab().setText(R.string.login),
LoginFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.economics),
EconFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.elections),
ElectionsFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.politics),
PoliticsFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.science),
ScienceFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.finance),
FinanceFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.religion),
ReligionFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.military),
MilitaryFragment.class, null);
mTabsAdapter.addTab(bar.newTab().setText(R.string.international),
InternationalFragment.class, null);
}
public void loginReport(int responseCode) {
DatabaseHandler db = new DatabaseHandler(getApplicationContext());
UserFunctions userFunctions = new UserFunctions();
Context context = getApplicationContext();
//login succeeded, sent when LoginTask doInBg sends a 1 to onPostExecute
if (responseCode == 1) {
loginButton = (Button)findViewById(R.id.loginButton);
loginButton.setText("Log Out");
int duration = Toast.LENGTH_LONG;
Toast toast = Toast.makeText(context, "Logged in.", duration);
toast.show();
bar.getTabAt(0).setText(db.getUserDetails().get(db.KEY_EMAIL));
//Log.v(TAG, db.getUserDetails().toString());
}
//login failed, sent when LoginTask doInBg sends a 0 to onPostExecute
if (responseCode == 0) {
int duration = Toast.LENGTH_LONG;
Toast toast = Toast.makeText(context, "Incorrect username/password", duration);
toast.show();
}
if (responseCode == 2) {
//logout button clicked, listened from within LoginFragment
//remove user from active sql db here rather than LoginFragment?!
bar.getTabAt(0).setText(R.string.login);
int duration = Toast.LENGTH_SHORT;
Toast toast = Toast.makeText(context, "Logged out", duration);
toast.show();
userFunctions.logoutUser(context);
}
}

The solution I adopted, after the suggestion of #Davek804 is that I replace the AsyncTask with a delayed runable like this:
private Runnable mMyRunnable = new Runnable()
{
public void run()
{
finish();
}
};
Toast.makeText(getBaseContext(),errorMessage , Toast.LENGTH_LONG).show();
Handler myHandler = new Handler();
myHandler.postDelayed(mMyRunnable, 3450);
So the effect will be the same.

I found the solution here
Instead of using :
task.execute();
use :
task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, null);