How to finish an android application?

Question

I need to finish an android application. For that i wrote

@Override
public void onBackPressed() {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setMessage("Are you sure You want to exit")
        .setCancelable(false)
        .setPositiveButton("YES"),
        new DialogInterface.OnClickListener() {
            // On
            // clicking
            // "Yes"
            // button

            public void onClick(DialogInterface dialog,int id) {
                System.out.println(" onClick ");
                closeApplication(); // Close Application method called
            }
        })
        .setNegativeButton("NO"),
        new DialogInterface.OnClickListener() {
            // On
            // clicking
            // "No"
            // button
            public void onClick(DialogInterface dialog,int id) {
                dialog.cancel();
            }
        });

        AlertDialog alert = builder.create();
        alert.show();
    }

    private void closeApplication() {
        System.out.println("closeApplication ");
        this.finish();
    }
}

But if any activity is not finished in the application, when i tried to exit the application that activity is finished first and the application is not exiting.. i tried 2 times to exit this application... How i can finish all the activities in an application when i need to exit... or is there any way to finish the entire application

Answer 1

To close application just call:

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

Otherwise due-to specific life-cycling of Android activities you can't be sure that application is closed/killed.

Answer 2

whenever you are starting a new activity use

myintent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(myintent);

and in manifest file mention that activity as

<activity android:name=".<Activity Name>" >
        <intent-filter>
        <action android:name="android.intent.action.VIEW"/>
     <category android:name="android.intent.category.DEFAULT" />
     </intent-filter>
       </activity>

Answer 3

Put this into your onClick or in onBackPressed :

moveTaskToBack(true);
finish()

Answer 4

Please read first this post from Google Android Developer Advocate Reto Meier : When to Include an Exit Button in Android Apps (Hint: Never)

What is th symptom that make you want to add an exit button ? If you need to clear the activity stack and always restart with a specific Activity, maybe you just have to tweak your activity manifest declaration with attributes like : android:clearTaskOnLaunch

Answer 5

Android is made in such a way that virtually NO application that was once opened, is closed.

Before mis-interpreting the statement, understand this.

"Whenever you exit your app, Android saves all the things the app was doing (called its state) and pushes the app in the background, calling the onStop() method. this is the new state of the application then, where the app isn't running, but isn't flushed out of the memory too. whenever you start the app again, it is resumed from the frozen state. Only when the memory, where frozen apps are kept, starts getting full, the Android GC flushes the app."

So conceptually, nothing goes out. when you hit "back" button while ur on the first activity, Android bundles the app and data, and freezes it.

Answer 6

I have an application with several Activities. I extended my Application class, and included a variable numActive. This is initialized to 0. Within each activity's onStart(), numActive is incremented, and in onStop() it is decremented. If the count reaches zero, the user has left my application entirely, and I close down my background tasks.

Answer 7

Shameless copy of NeTeInStEiN's answer as I found it so useful (please up-vote his answer): Sending a running application to background programmatically

You can use either:

boolean sentAppToBackground = moveTaskToBack(true);

if(!sentAppToBackground){
  Intent i = new Intent();
  i.setAction(Intent.ACTION_MAIN);
  i.addCategory(Intent.CATEGORY_HOME);
  this.startActivity(i);
}

More information here: http://developer.android.com/reference/android/app/Activity.html#moveTaskToBack(boolean)

Or simply:

Intent i = new Intent();
i.setAction(Intent.ACTION_MAIN);
i.addCategory(Intent.CATEGORY_HOME);
this.startActivity(i);

According to Romain Guy a Android Framework Engineer, "You cannot simulate a press on the Home key.". So beware...

Check: http://osdir.com/ml/Android-Developers/2010-03/msg01887.html

Updated this answer according to: moveTaskToBack(true) returns false always

Answer 8

according to this answer ,

just write this.finishAffinity(); and done!

Answer 9

要关闭应用程序，您也可以将“ System.exit（0）”设为标准0或使用任何退出代码。