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Android completely force quitting an app

I have a login activity. After login, the Main activity is started, which uses fragments for user navigation. I want a button in the nav drawer of my main activity which will completely close the app
Now, I have seen many many threads on this and have tried implementing their solutions. For example:
I have tried finishAffinity() in my Main activity, which should close the current activity as well as all parent activities
I have tried using finish() on the Login activity as soon as I bring up the Main Activity, and then calling finish() again when the user clicks the button
The highest voted answer for this question: Close application and remove from recent apps/, also does not seem work. First, android:autoRemoveFromRecents="true" requires API > 21, but even if I set the minimum SDK version to 21, the app still remains in the list
Finally, I have tried using an Intent when the user clicks the quit button and navigating back to the Login activity, and setting flags with an exit extra, and then finishing the Login activity (i.e. exit android application programmatically)
None of these are working. They will all close the Main Activity, and maybe even close the Login activity. But if the user clicks the app list/current apps/open apps key (the square soft key on most phones), the app is still visible there. When the app is clicked in that list it will take me back to the Login activity screen (I'm unsure if this is starting the app from fresh, or whether its just taking me to the previous Login screen which didn't close)
Out of desperation I have even tried System.exit(0), which I know is bad, but even that doesn't remove the app from the app list
So, how do I programmatically completely quit an app and remove all traces of it being open?
EDIT: I was too hasty in claiming one of the answers below didnt work (see italics above). The answer does remove the app correctly

I think this is the solution you're looking for.
You might consider having another activity named ExitActivity which will be called when you try to exit from your application. The trick here is, the ExitActivity will have android:autoRemoveFromRecents set to true in the manifest file, so that your instance will be cleared automatically from the recents.

Based on my research:
There is no way to force quite an application in android. You can only pause an activity. The discretion to quit an app lies totally with android framework which it does on checking the memory and resource utilization of apps. I could not find the official link for now, but I had read it earlier.

manage it by the OS. bring up the home screen.
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);

Why App after crash lands on some activity and does not exit

I have noticed this dual behavior of app crash in different applications. Sometimes on crashing it simply exits the app but other times it lands on some previous activity. Is this a known behavior or is there any logic behind this which can be handled. Tried to search it on SO but couldn't find right combination of keywords for my problem.
Thanks

It depends on the FLAGS you created the Intent with. For example, with CLEAR_TOP If the activity being started is already running in the current task, then instead of launching a new instance of that activity, all of the other activities on top of it are destroyed and this intent is delivered to the resumed instance of the activity (now on top), through onNewIntent()).
When an Activity crashes if there are no more back-stacked activities of the same app, it will simply exit and show the device's home.

What's the difference between opening an app from the applications screen and the recently used apps list? (android

Can anyone tell me what the difference is between opening an app from the applications screen and opening it from that recently used apps list that pops up when you long-press the home button?
I didn't even know that recently used list existed until a friend managed to break my app by launching it from there. He tried twice and got the same force quit, but when he launched it from the applications screen it opened fine.
The error log told me that a nullPointerException occurred in the getCount method on my ArrayAdaptor for my ListView.
Anyway I just wondered if there was a difference that I need to know about and adapt my code to deal with?

AFAIK, If your application is completely shutted down, launch from applications screen and recently used apps list should have no difference, both refresh start your application and open your application's MainActivity (by stack-push your application's MainActivity into a newly created task)
However, as Android is multi-task OS, your application can be put into background in standby mode i.e. open your application then short-press home button, this is not same as press back button. If you haven't override these key pressed in your application, press back button several times with pop all your activities off from activity stack and finally kill your application, whereas press home button will bring System's HomeActivity into foreground hence flip your application (AKA. task with activity stack) into background.
Things becomes more interesting here, depend on which value your configure your activity's android:launchMode in AndroidManifest.xml, if you use standard or singleTop:
1. launch app from recently used apps list always bring your standby activity back to foreground, i.e. re-order activity stack.
2. launch app from applications screen will create a new instance of your MainActivity and open it, i.e. push a newly created MainActivity into activity stack, so now you have two instances in your application's activity stack
If you use singleTask or singleInstance:
2. launch app from applications screen will use the standby MainActivity (if exist) in your application's activity stack and re-open it, i.e. re-order activity stack.
Checkout Tasks and Back Stack to see how different configurations may affect your application's activity stack behaviour.

I believe there should be no difference. These are the lifecycle methods I typically see when pressing the home button from an activity, on android 2.3.4
onPause
onStop
then when I use either the icon or previous applications to navigate back, I see
onRestart
onStart
onResume
Now, in some cases the system will tell your activity to finish while you are away (or immediately when you return if an orientation change occurred). Then you will see onDestroy, and the following when you navigate back
onCreate
onStart
onResume
I don't think there is anything mysterious going on here. According to the Activity documentation, there are only four states that a process can be in, and both of these fall under background activity.

There shouldn't be any difference in how the activity is launched from history, apart from the fact that the launching Intent will have the FLAG_ACTIVITY_LAUNCHED_FROM_HISTORY set.

Here's an easy way to think about it. All of your activities are launched form Intents. Holding down the home button allows you to open that activity using the last intent that launched it. This can give you some unexpected results however. For instance, if you are able to launch your activity from something special like a widget.

How to close an application when the Home button is pressed

Hi I have application with more than 20 activities.I want to close my app when Home button is pressed.

There is no notion of "close my app" in Android. Android will get rid of your activities, followed by your process, after some period of inactivity by the user.

You could use the launchMode and clearTaskOnLaunch flags on your root activity from your AndroidManifest.xml:
android:launchMode="singleTask"
android:clearTaskOnLaunch="true"
When you again start your app, all activities will be killed.

You don't want to do System.exit() -- that's not how the Android Activity Lifecycle normally works (read this also).
What you should do is move the App to the background with moveTaskToBack(). Android will then keep your app running in the background, and kill it if it's unused and something needs its resources later.
If you want it to close all of the open Activities when your App is no longer visible, you can set noHist = "True" for all of the child activities (leave the main activity with noHist = "False", though). This will make it where instead of reopening your application on the last Activity they were on, it will open it on the "main" activity (i.e. it will be as if they just restarted the app).
Anyhow, read through the following answers for more information: Close application and launch home screen on Android

I have the same problem. Im writing a banking app and am required, by contract, to log off the user (or exit) when the app is put into background. There are obvious security concerns there.
There are a couple of ways Im looking to do this:
1. Intercept home button (and back button for the root activity) key press events to call logoff and/or finish()
2. In the onStop() method, for every activity, detect whether the activity is being stopped due to a new activity being show - if not, assume app is being put to background so logoff and/or finish()
The first may not work if a notification is brought to the front then the user clicks home (I havent investigated yet). Or maybe there are other ways for an app to be put into the background without pressing these buttons
The second way sounds messy & difficult to maintain
Id welcome any other ideas
Drapes
I know android has been designed this way, but it seems naive to think that apps wouldnt want an applicationOnStop event

Hi guys what I understood is that u need to know when app goes in background and how to detect it and if I am wrong plz correct me----
The user can go in background if ur app does not provide any way by pressing Back key or Home Key.
You need to use methods "dispatchKeyEvent(KeyEvent event)" to get home key event or back key event and after getting the event you can execute your task.
you can even restrict user from pressing any key but u can not control the home key.

Forcing an activity to be added to the history stack

I have an activity which is declared in my manifest with android:noHistory="true", and 90% of the time, this is the desired functionality. This particular activity doesn't need to be saved in the application's history, and the application's UI flow is greatly complicated when it is in the history and needs to be manually removed by calling finish() every time the activity would otherwise be added to the stack.
The problem is, that this activity has the ability for the user to send an email, which is of course accomplished by creating an Intent with the ACTION_SEND property. When the user presses the "back" button from this activity, the next one to be shown in the stack is actually the one underneath my activity. Is there any way that I can force Android to add my activity in the history stack before presenting the ACTION_SEND intent?

I look forward to be proven wrong but I believe that the history stack is updated when the activity is created. At first I would suggest the rather hackish solution of launching a "proxy" intent that would be pushed onto the stack which could then call the e-mail intent and would be smart enough to launch the proper intent on the way back.
I'll update my answer if I find something in my notes.