how to close android app completely

Question

I created an android application with a logout option in onCreateOptionsMenu. The Logout works perfectly but when I press the back button again it takes me to the previous activity, and when it gets a null value it redirects to login screen. Now my login screen appears again and again. I want to close the app completely when I press the back button but don't know how.

Here is my code to handle the back button press in the login screen:

@Override
public void onBackPressed() {
    new AlertDialog.Builder(this)
        .setTitle("BidNEMO")
        .setMessage("Are you sure you want to exit?")
        .setNegativeButton(android.R.string.no, null)
        .setPositiveButton(android.R.string.yes, new OnClickListener() {
         public void onClick(DialogInterface arg0, int arg1) {
         Main.super.onBackPressed();
         finish();
         }
         }).create().show();
     }

please help guyss..

Realize

Try this – Trencherman

possible duplicate of Android: Proper Way to use onBackPressed() – Liverwort

Answer 1

To Quit Application on Button click use this code :

Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
startActivity(intent);

Try it..

To kill the complete app and remove it from Runningapp list kill the app through its pid(its nasty)... use this lines before above code.

int pid = android.os.Process.myPid();
android.os.Process.killProcess(pid);

Dameron

you are just calling home via intent. How is it different from calling another activity's intent. i dont think the app will close. instead it will minimize. – Esch

whats your requirement ?? – Dameron

I just want to make sure that the above code Actually Quits the app or just brings home screen on front. just to be clear :) – Esch

It Quits the app... Do check it – Dameron

Only if you also include super.onBackPressed() and no other activity is in the backstack other wise it does't. – Esch

It was a general answer.... i have just posted the required code which can be used anywhere.. and i have clearly mentioned on Button click. – Dameron

let us continue this discussion in chat – Esch

KillProcess should be killProcess, the first letter K be small k, fixed. – Runion

Thank you guys! Saved my neck, also the chat was helpful! – Screens

Answer 2

If you want to close application completely you should use finishAffinity(); instead of finish() . It will clear all stack of activities previously opened by an application.

Jacquesjacquet

finishAffinity() is only available in API level 16 or higher. – Shine

Answer 3

For API 21 and up

finishAndRemoveTask()

You can call this to close the app completely. All activities will finish() and the app is removed from the task list.

Laywoman

it didn't work when I have another activity below current activity. finishAffinity worked however. – Archean

You can check before if the activity is the root activity with isTaskRoot(). Then it works great. – Qulllon

Answer 4

To Finish an Activity I'm using this code:

public void appExit () {
    this.finish();
    Intent intent = new Intent(Intent.ACTION_MAIN);
    intent.addCategory(Intent.CATEGORY_HOME);
    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(intent);
}  //close method

or kill Process with this code:

int pid = android.os.Process.myPid();
android.os.Process.killProcess(pid);

Herwin

KillProcess should be killProcess, the first letter K be small k, fixed. – Runion

Answer 5

For Xamarin Users:

int pid = Android.OS.Process.MyPid();
Android.OS.Process.KillProcess(pid);

put it in your OnDestroy() function.

Edit:

After investigating it thoroughly, I found out that even the above code I wrote does not "Kill" the app totally (deleting it from task manager - "recent apps"). Eventually, after a lot of code tryouts, I managed to figure something out, Overriding "Finish" functions with this code:

public override void Finish()
    {
        if (Android.OS.Build.VERSION.SdkInt >= BuildVersionCodes.Lollipop)
        {
            base.FinishAndRemoveTask();
        }
        else
        {
            base.Finish();
        }
    }

this is the sole solution for that question!

Translate

Answer 6

Even if it looks ok killing process will cause you headache in future. You can ensure this by following use case:

1. call several activities to populate activities stack
2. call android.os.Process.killProcess(pid);
3. open your application

OBSERVED: Your application opens not from main activity in inconsistent way. This is because Android consider killing of process like crash.

You can find more detailed information here: Is quitting an application frowned upon?

Fichu

Answer 7

android.os.Process.killProcess(android.os.Process.myUid());

I think this is better. How about it ?

Belga

Answer 8

Closing the application with process removal, it gives the result of a smooth closing and removal of all application processes after 100 milliseconds:

---

override fun exit() {
    coroutine.launch(Dispatchers.Main) {
        finishAndRemoveTask()
        delay(100)
        exitProcess(0)
    }
}

Lakin

Answer 9

In my case i used this method. It already worked for me. I use this technique with Jetpack Compose peoject.

val context = LocalContext.current

BackHandler {
    val intent = Intent(Intent.ACTION_MAIN)
    intent.addCategory(Intent.CATEGORY_HOME)
    context.startActivity(intent)
}

Fao