Android: Previous activity returns on back button press after finish()

Question

I have 2 activities. The first activity is the LogoActivity. After 3 seconds I start the second activity that is my MainActivity.

private void startCountDown(int duration, int interval) {
    CountDownTimer mCountDownTimer = new CountDownTimer(duration, interval) {
        @Override
        public void onTick(long millisUntilFinished) {
            // nothing
        }

        @Override
        public void onFinish() {
            startActivity(MainActivity.class);
            finish();
        }
    };

    mCountDownTimer.start();
}

startActivity(Class mClass) is a method that I created to start any activity just by giving the class.

Now I am in the MainActivity. If I exit by pressing home button and return back I see the MainActivity, but if I press back button from MainActivity and reopen the app from background the LogoActivity show up first.

I dont want the users to see the LogoActivity everytime they press back button(button from phone, not activity) from MainActivity and restore it from background.

Why is the LogoActivity shown if I called finish()?

@JoeFrostick I have changed nothing in my manifest. LogoActivity is my LAUNCHER activity, but I didnt expected it to open again if I called finish(). — Chris, Nov 19 '15 at 10:54
I don't know why back return to finish activity but you can disable the back button from your MainActivity... — AsfK, Nov 19 '15 at 10:54
Just humour me - want to see if you've set LogoActivity as MainActivity's parent — JoeyJubb, Nov 19 '15 at 10:55
@JoeFrostick No I haven't. But my problem is when I press back button from phone, not from the activity that appears when you set a parent for the activity. — Chris, Nov 19 '15 at 10:57
check if this link helps http://stackoverflow.com/questions/3141996/android-how-to-override-the-back-button-so-it-doesnt-finish-my-activity — Priya, Nov 19 '15 at 11:02

score 2 · Accepted Answer · answered Nov 19 '15 at 10:56

2

When you press back button, the instance of MainActivity is destroyed.

And then you come back to this task stack again, the LogoActivity is your default Activity so the system creates one instance of it for you.

You can make the MainActivity the default Activity in manifest.xml

<activity android:name=".MainActivity" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

And start LogoActivity in the onCreate method of MainActivity so the user will see LogoActivity first.

After 3 seconds, finish the LogoActivity.

answered Nov 19 '15 at 10:56

Eric Liu

1,516
13
19

I tested activity lifecycle and what you said is correct. Would be a good practice to use this method or is there any other alternative? – Chris Nov 19 '15 at 11:09
Another to to do it is to use one Activity, 2 Fragments. – Eric Liu Nov 19 '15 at 11:19
2 fragments doesnt worth the effort, so I will use the first method. Thanks for your help. – Chris Nov 19 '15 at 11:23

score 1 · Answer 2 · answered Nov 19 '15 at 11:30

Why is the LogoActivity shown if I called finish()?

The answer is- When you start your application than your system checks app's ManifestFile to get An activity whose Intent-filter action and category is set to "android.intent.action.MAIN" and "android.intent.category.LAUNCHER" .

This activity is your app's launcher(first) activity. (I think ,In your case it is LogoActivty).

When you starts your app "Android system" adds this activity in your Activity stack.As you start some other activity that one also add to the top of Activity stack.

On finish an activity it will removed from Activity stack.

whenever you start your app "Android system" traces Activity stack to get top activty.And start your application from that one.

If it found Activity stack empty the system starts your app with your app's launcherActivity.

In your case you finishes both activities.Thus your Activity stack becomes empty and it start you app with LogoActivity.

SOLUTION

override onBackPress method in MainActivity and dont call finish. But In this case your Activity will not closed onbackPress.

Or make your MainActivity launcher activity

Your answer is very good but I already accepted an answer. I choosed to make MainActivity my launcher activity because I will show LogoActivity just at first app start. Thanks for your activity stack explanations! — Chris, Nov 19 '15 at 11:37

score 0 · Answer 3 · answered Nov 19 '15 at 10:51

0

Because it is different using Back vs Home button. See Android Activity lifecycle: http://developer.android.com/intl/es/reference/android/app/Activity.html

answered Nov 19 '15 at 10:51

Alberto Méndez

1,044
14
31

score 0 · Answer 4 · answered Nov 19 '15 at 11:00

0

Try overiding onBackPressed() method

@Override
public void onBackPressed() {
    moveTaskToBack(true);
}

answered Nov 19 '15 at 11:00

Collins Abitekaniza

4,496
2
28
43

score 0 · Answer 5 · answered Nov 19 '15 at 11:02

0

Try to control the onBackPressed() method of your activity.

answered Nov 19 '15 at 11:02

Jorge Díaz

1
1

2

Welcome to StackOverflow! Please, expand your answer. Explain your solution in more details, provide an example. Brevity is acceptable, but fuller explanations are better. – naXa stands with Ukraine Nov 19 '15 at 12:06

score 0 · Answer 6 · answered Nov 20 '15 at 04:38

0

You can use activity attributes in manifest to achieve the same.

"android:finishOnTaskLaunch"

For more please visit http://developer.android.com/guide/topics/manifest/activity-element.html

answered Nov 20 '15 at 04:38

Ajitha

717
1
7
30

score 0 · Answer 7 · answered Feb 03 '16 at 09:47

0

Always use intent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);

answered Feb 03 '16 at 09:47

IDontEvenKnow

122
1
1
9

Why did you just post the same answer to two different questions? This answer is the same as this: http://stackoverflow.com/a/35173592/1987598. – Mathias Müller Feb 03 '16 at 10:13
Because it fixes them both. – IDontEvenKnow Feb 04 '16 at 08:26
Fair enough. Usually, when the answers to two separate questions are the same, one should be closed as a duplicate of the other. – Mathias Müller Feb 04 '16 at 08:31

score -1 · Answer 8 · answered Nov 19 '15 at 10:56

-1

You have to use Intent for new activity. Like this.

startActivity(new Intent(LogoActivity.this, MainActivity.class));
finish();

Instand of only startActivity(MainActivity.class)

answered Nov 19 '15 at 10:56

Jaydip

592
5
27

I said that ``startActivity(Class mClass)`` is a method I created and contains the Intent. So your answer is irrelevant. – Chris Nov 19 '15 at 10:58

Android: Previous activity returns on back button press after finish()

8 Answers8