Develop Reference

Logging out of an application

I am trying to implement the logout method in my android application
and write the below code. Main Activity is a login activity and ChoosingProcActivity is an activity which contains logout button.
when I press logout button it moves me to Main Activity but when I open application next time it directly moves me to ChoosingProcActivity.
in addition to that when I log in successfully and then go back or press back it show Main Activity (login). how can I avoid this?
are shared preferences wrong?
Main Activity code
package com.example.lenovo.tactic;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Vibrator;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ExecutionException;
public class MainActivity extends AppCompatActivity {
EditText email_input,password_input;
TextView reset;
Button btnLogin;
Boolean isLogedBefore = false;
Vibrator v;
String organizer_ID;
SharedPreferences test_name;
final String loginURL = "http://tactickevent.com/phpApp/loginApp.php";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
email_input = findViewById(R.id.etUserName);
password_input = findViewById(R.id.etPassword);
btnLogin = findViewById(R.id.btnLogin);
test_name = getSharedPreferences("NAME", Context.MODE_PRIVATE);
test_name.getString("email", "");
test_name.getString("organizer_ID", "");
// if(isLogedBefore == true){
boolean is = test_name.getBoolean("isLoged", false);
if (is==true) {
Intent intent = new Intent(MainActivity.this, ChoosingProcActivity.class);
startActivity(intent);
// }
}
v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
btnLogin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
validateUserData();
}
});
}
private void validateUserData() {
//first getting the values
final String email = email_input.getText().toString();
final String password = password_input.getText().toString();
//checking if email is empty
if (TextUtils.isEmpty(email)) {
email_input.setError("أدخل البريد الالكتروني من فضلك");
email_input.requestFocus();
// Vibrate for 100 milliseconds
v.vibrate(100);
btnLogin.setEnabled(true);
return;
}
//checking if password is empty
if (TextUtils.isEmpty(password)) {
password_input.setError("أدخل كلمة السر من فضلك");
password_input.requestFocus();
//Vibrate for 100 milliseconds
v.vibrate(100);
btnLogin.setEnabled(true);
return;
}
//validating email
if (!android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
email_input.setError("أدخل بريد الكتروني صحيح");
email_input.requestFocus();
//Vibrate for 100 milliseconds
v.vibrate(100);
btnLogin.setEnabled(true);
return;
}
//Login User if everything is fine
//first getting the values
//String emaill = email_input.getText().toString();
// String passwordd = password_input.getText().toString();
loginUser(email,password);
}
private void loginUser(final String email,final String password) {
RequestQueue queue = Volley.newRequestQueue(this);
//Call our volley library
StringRequest stringRequest = new StringRequest(Request.Method.POST,loginURL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
// Toast.makeText(getApplicationContext(),response.toString(), Toast.LENGTH_SHORT).show();
JSONObject obj = new JSONObject(response);
if (obj.getInt("value")== 1) {
organizer_ID = obj.getString("organizer_ID");
//storing the user in shared preferences
//SharedPref.getInstance(getApplicationContext()).storeID(organizer_ID);
//starting the ChoosingProcActivity
SharedPreferences.Editor editor = test_name.edit();
editor.putBoolean("isLoged",true);
editor.putString("email", email);
editor.putString("organizer_ID", organizer_ID);
//apply
editor.commit();
Toast.makeText(getApplicationContext(), "تم تسجيل الدخول بنجاح", Toast.LENGTH_SHORT).show();
startActivity(new Intent(getApplicationContext(), ChoosingProcActivity.class));
//finish();
// startActivity(new Intent(getApplicationContext(), ChoosingProcActivity.class));
} else{
Toast.makeText(getApplicationContext(),"هناك خطأ في كلمة السر أو البريد الالكتروني ", Toast.LENGTH_SHORT).show();
//getting user name
//Toast.makeText(getApplicationContext(), obj.getString("messagee"), Toast.LENGTH_SHORT).show();
//storing the user in shared preferences
//SharedPref.getInstance(getApplicationContext()).storeUserName(organizer_ID);
//starting the profile activity
//finish();
//startActivity(new Intent(getApplicationContext(), ChoosingProcActivity.class));
}
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getApplicationContext(),"Connection Error"+error, Toast.LENGTH_SHORT).show();
error.printStackTrace();
}
}) {
//email key mean the value that will send to php in $_POST["email"];
//password key mean the value that will send to php in $_POST["password"];
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("email", email);
params.put("password", password);
return params;
}
};
queue.add(stringRequest);
/*
String type = "login";
BackgroundWorker backgroundWorker = new BackgroundWorker(this);
backgroundWorker.execute(type, email, password);
try {
JSONObject jsonObject = new JSONObject(result1);
SharedPreferences.Editor editor = test_name.edit();
editor.putBoolean("isLoged",true);
editor.putString("email", email);
editor.putString("organizer_ID", jsonObject.getString("organizer_ID"));
//apply
editor.commit();
*/
}
}
code of second activity
package com.example.lenovo.tactic;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
public class ChoosingProcActivity extends AppCompatActivity {
Button eventBTN, subeventBTN;
SharedPreferences test_name;
String emailToPass,organizer_ID;
SharedPreferences preferences;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_choosing_proc);
eventBTN= (Button)findViewById(R.id.BtnEvent);
subeventBTN= (Button)findViewById(R.id.BtnSubEvent);
test_name = getSharedPreferences("NAME", Context.MODE_PRIVATE);
emailToPass= test_name.getString("email", "");
organizer_ID= test_name.getString("organizer_ID", "");
eventBTN.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(ChoosingProcActivity.this, EventProcActivity.class);
startActivity(intent);
}
});
subeventBTN.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(ChoosingProcActivity.this, SubeventProcActivity.class);
startActivity(intent);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu){
MenuInflater menuInflater = getMenuInflater();
menuInflater.inflate(R.menu.main_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item){
if(item.getItemId() ==R.id.logout)
{
preferences =getSharedPreferences("Name",Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.clear();
editor.commit();
finish();
}
return true;
}
}

You can finish your activity every time the test is true so that it can no longer be accessible from the stack.
boolean is = test_name.getBoolean("isLoged", false);
if (is) {
Intent intent = new Intent(MainActivity.this, ChoosingProcActivity.class);
startActivity(intent);
finish();
}

I am assuming that your MainActivity is the first one to get launched when opening the app.
In your MainActivity add this:
#Override
protected void onStart() {
super.onStart();
if (SharedPrefManager.getInstance(this).isLoggedIn()) {
Intent intent = new Intent(this, ChoosingProcActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finish();
}
}
What it does during startup of your app it will query if there is someone already logged in if yes it will go to the ChoosingProcActivity. I am assuming that in your SharedPrefManager implementation you have a code to know if there is a logged in user.
In your login method uncomment the finish() method
startActivity(new Intent(getApplicationContext(), ChoosingProcActivity.class));
//finish();
After successfull login, if you press back button you will not see the MainActivity.
In your ChoosingProcActivity it will look like this:
#Override
protected void onStart() {
super.onStart();
if (!SharedPrefManager.getInstance(this).isLoggedIn()) {
Intent intent = new Intent(this, MainActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finish();
}
}
Basically, it will ask if there is currently logged in user if not, it will go back to the MainActivity.
EDIT In Logout you may use this as basis from your code,
logoutComponent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
SharedPrefManager.getInstance(getActivity()).clear();
Intent intent = new Intent(ChooseProcActivity.this, MainActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
}
});

Android Studio Splash screen is looping indefinitely and will not stop

I'm really new to coding and have almost no idea what I'm doing.
I need to get this splash screen to work but it keeps looping infinitely back between the splash screen and mainactivity and I have no idea why, I took the code off some YouTube video and the video had no explanation too so I'm stuck.
This is the code for mainactivity:
package sg.edu.tp.project1;
import android.content.Intent;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
public class MainActivity extends AppCompatActivity {
private static int SPLASH_TIME_OUT = 1000;
private ImageButton Search01;
private ImageButton Mymusic;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Search01 = (ImageButton) findViewById(R.id.Search);
Mymusic = (ImageButton) findViewById(R.id.Mymusic);
}
{ new Handler().postDelayed(new Runnable(){
#Override
public void run() {
Intent homeIntent = new Intent(MainActivity.this,
HomeActivity.class);
startActivity(homeIntent);
finish();
}
},SPLASH_TIME_OUT);
}
public void gotoSearchpage(View view){
Intent intent = new Intent(this, searchpage.class);
this.startActivity ( intent );
}
public void gotoMymusic(View view){
Intent intent = new Intent(this, myMusic.class);
this.startActivity ( intent );
}
public void gotoPlaylist(View view){
Intent intent = new Intent(this, playlist.class);
this.startActivity ( intent );
} }
and this is the code for the splash screen:
package sg.edu.tp.project1;
import android.content.Intent;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class HomeActivity extends AppCompatActivity {
private static int SPLASH_TIME_OUT = 1000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
}
{ new Handler().postDelayed(new Runnable(){
#Override
public void run() {
Intent homeIntent = new Intent(HomeActivity.this,
MainActivity.class);
startActivity(homeIntent);
finish();
}
},SPLASH_TIME_OUT);
}
}

First of all... use AsyncTask in Splash screen it is best practice to do background initialization and checks.
Second you don't need handler in MainActivity.
remove this code from MainActivity... it is redirecting u to HomeActivity.
{ new Handler().postDelayed(new Runnable(){
#Override
public void run() {
Intent homeIntent = new Intent(MainActivity.this,
HomeActivity.class);
startActivity(homeIntent);
finish();
}
},SPLASH_TIME_OUT);
and change your HomeActivity(Splash) like this..
public class HomeActivity extends AppCompatActivity {
private static int SPLASH_TIME_OUT = 1000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
new Loader().execute();
}
private class Loader extends AsyncTask<Void,Void, Void>{
#Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
try {
Thread.sleep(SPLASH_TIME_OUT);
} catch (InterruptedException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
//if(pd!=null) pd.dismiss();
Intent intent = new Intent(HomeActivity.this,MainActivity.class);
startActivity(intent);
HomeActivity.this.finish();
}
}
}

Splash screen Android App has stopped

I want to make a splash screen for my android app. I have written following codes in welcomescreen.java in android studio. But after running the app, the app has stopped. :( What shall I Do now?
package com.mateors.welcomescreen;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class WelcomeScreen extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_welcome_screen);
Thread myThread = new Thread(){
#Override
public void run() {
try {
sleep(5000);
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
startActivity(intent);
finish();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
myThread.start();
}
}

private static int SPLASH_TIME_OUT = 1500;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash_screen);
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
Intent i = new Intent(WelcomeScreen.this, MainActivity.class);
startActivity(i);
finish();
}
}, SPLASH_TIME_OUT);
}
try the above code snippet

Try with following code:
package com.mateors.welcomescreen;
import android.support.v7.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
public class WelcomeScreen extends AppCompatActivity {
private static int SPLASH_TIME_OUT = 5000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_welcome_screen);
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
Intent i = new Intent(WelcomeScreen.this, MainActivity.class);
startActivity(i);
finish();
}
}, SPLASH_TIME_OUT);
}
}

Delay after the splash screen

My problem is, if I set my splash as a Dialog by adding this line in the manifest there's a delay: android:theme="#android:style/Theme.Holo.Dialog.NoActionBar"
After the splash screen disappears it takes around 6 seconds or more to the main activity to appear.
How can I make this delay disappear?
Splash code:
public class SplashActivity extends Activity {
private final int DURATION = 3000;
private Thread mSplashThread;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
mSplashThread = new Thread() {
#Override
public void run() {
synchronized (this) {
try {
wait(DURATION);
} catch (InterruptedException e) {
} finally {
finish();
Intent intent = new Intent(getBaseContext(),
MainActivity.class);
startActivity(intent);
}
}
}
};
mSplashThread.start();
}
#Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
synchronized (mSplashThread) {
mSplashThread.notify();
}
}
return true;
}
}

Rather than using splash as dialogue you can do all your background work in a splash screen activity and then start your main activity..if you need dialogue animation then you can use animation like this.
overridePendingTransition( R.anim.come_up, R.anim.go_down );
By this you can manage your activity switching time.

i am not sure that this answer is appropriate but i have done it like this :
#Override
public void run()
{
// TODO Auto-generated method stub
startActivity( new Intent ( SplashActivity.this , MainActivity.class ) ) ;
}
#Override
protected void onStart()
{
super.onStart();
if(!isClosed)
splashHandler.postDelayed(this, "putYourTimeHere");
}

This is working for me at its best..
final int splashTimeOut = 3000;
Thread splashThread = new Thread(){
int wait = 0;
#Override
public void run() {
try {
super.run();
while(wait < splashTimeOut){
sleep(100);
wait += 100;
}
} catch (Exception e) {
}finally{
startActivity(new Intent(SplashScreen.this,LoginActivity.class));
finish();
}
}
};
splashThread.start();

this is the code for splashscreen display with some time delay
..
here set splash image in drawable in splash_screen.xml.
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.view.Window;
import android.widget.Toast;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
public class SplashScreen extends Activity {
LocationManager locationManager;
String provider, formattedDate, imeid;
double lat, lon;
#SuppressLint("NewApi")
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.splash_screen);
Calendar c = Calendar.getInstance();
SimpleDateFormat df = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss");
formattedDate = df.format(c.getTime());
new Handler().postDelayed(new Runnable() {
public void run() {
Log.i("JO", "run");
Intent in = new Intent(SplashScreen.this,SecondActivity.class);
//in.putExtra("refreshclick", clickRefreshButton);
//in.putExtra("Current_Date", formattedDate);
// in.putExtra("ImeiId", imeid);
//Log.i("JO", "Current_Date"+formattedDate+";
ImeiId"+imeid+";lat"+lat+"lon"+lon);
startActivity(in);
finish();
}
}, 1000);
}
}

new Handler().postDelayed(new Runnable() {
#Override
public void run() {
Intent i = new Intent(SplashActivity.this, MainActivity.class);
startActivity(i);
finish();
}
}, DURATION);
}

how to wake a thread from sleep in android

I have an activity thats waiting for the user press on an image. if the user dont press anything in 3 second i want the activity to close (finish()).
thats my code:
private final int delay = 3000;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.after_hangup);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
final ImageView pressToLaunchbrowser = (ImageView) findViewById(R.id.after_hang_up_image);
pressToLaunchbrowser.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD); // if we want to open the device.
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(url));
startActivity(intent);
Thread.interrupted();
}
});
new Thread() {
public void run() {
try {
Thread.sleep(delay);
finish();
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}.start();
}}
My question is how can i wake the Thread if the press was made? i tried Thread.interrupted(); but its not working. the thread still waits 3 seconds if i press or not. Thanks!

Threads are not recommended to use in Android..use Handler to manage time-dependant operations..for example, instead of new Thread().., try
Handler handler = new Handler();
handler.postDelayed('runnable-that-will-finish-activity', 3000);
and in onclicklistener:
handler.remove('runnable-that-will-finish-activity') ;

import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.WindowManager;
import android.widget.ImageView;
public class NewActivity extends Activity {
private final int delay = 3000;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.after_hangup);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
final ImageView pressToLaunchbrowser = (ImageView) findViewById(R.id.after_hang_up_image);
final Handler handler = new Handler();
handler.postDelayed(finishRunnable, delay);
pressToLaunchbrowser.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
// // if we want to open the device.
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(url));
startActivity(intent);
handler.removeCallbacks(finishRunnable);
}
});
}
private Runnable finishRunnable = new Runnable() {
#Override
public void run() {
finish();
}
};
}