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I'm working on an app and encountered a strange behavior on 8.1 Devices (Pixel2, Nexus5x), so I wrote a small App to verify this behavior.

MainActivity is locked to portrait mode while LandscapeActivity is locked to landscape. MainActivity starts the LandscapeActivity for Result. Screen Switches from portrait to landscape as expected. When LandscapeActivity is finished it propagates the Result to MainActivity, while switching back to portrait (as expected).

But Sometimes I encounter kind of a bug here. After onActivityResult in MainActivity it switches from portrait to landscape to switch back to portrait immediately. While I can handle the state, it still looks nasty.

For traceability I will post everything to rebuild it.

What can I do to prevent it? Also note that it does not happen every time, and as far as I can test on 8.1 devices ONLY. It seems fine on android devices below 8.1

EDIT: Added android:configChanges="orientation|screenSize" to my manifest as @Floern suggested in his answer without success. A confirmation on a platform bug will be an acceptable answer, too

Manifest

<application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity"
            android:screenOrientation="portrait"
            android:configChanges="orientation|screenSize">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

    </application>

MainActivity

public class MainActivity extends AppCompatActivity {

    public static final String TAG = MainActivity.class.getSimpleName();

    private static final int REQ_CODE = 878;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "onCreate: savedInstanceState=" + savedInstanceState + ", orientation=" + orientation());
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(MainActivity.this, LandscapeActivity.class);
                startActivityForResult(intent, REQ_CODE);

            }
        });
    }

    @Override
    protected void onResume() {
        Log.d(TAG, "onResume: orientation=" + orientation());
        super.onResume();
    }

    @Override
    protected void onPause() {
        Log.d(TAG, "onPause: orientation=" + orientation());
        super.onPause();
    }

    @Override
    protected void onStart() {
        Log.d(TAG, "onStart: orientation=" + orientation());
        super.onStart();
    }

    @Override
    protected void onStop() {
        Log.d(TAG, "onStop: orientation=" + orientation());
        super.onStop();
    }

    @Override
    protected void onDestroy() {
        Log.d(TAG, "onDestroy: orientation=" + orientation());
        super.onDestroy();
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        Log.d(TAG, "onActivityResult: orientation=" + orientation());
        if (requestCode == REQ_CODE){
            Toast.makeText(this, "Result=" + data.getStringExtra(LandscapeActivity.KEY_DATA), Toast.LENGTH_LONG).show();
        }
    }

    String orientation(){
        return getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE ?  "Landscape" : "Portrait";
    }
}

LandscapeActivity

public class LandscapeActivity extends AppCompatActivity{

    public static final String TAG = LandscapeActivity.class.getSimpleName();

    public static final String KEY_DATA = "DATA";
    static int COUNTER = 0;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "onCreate: savedInstanceState=" + savedInstanceState + "orientation=" + (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE ?  "Landscape" : "Portrait"));
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent data = new Intent();
                COUNTER++;
                data.putExtra(KEY_DATA, "Runned " + COUNTER + " times");
                setResult(RESULT_OK, data);
                finish();
            }
        });
    }

    @Override
    protected void onResume() {
        Log.d(TAG, "onResume: orientation=" + orientation());
        super.onResume();
    }

    @Override
    protected void onPause() {
        Log.d(TAG, "onPause: orientation=" + orientation());
        super.onPause();
    }

    @Override
    protected void onStart() {
        Log.d(TAG, "onStart: orientation=" + orientation());
        super.onStart();
    }

    @Override
    protected void onStop() {
        Log.d(TAG, "onStop: orientation=" + orientation());
        super.onStop();
    }

    @Override
    protected void onDestroy() {
        Log.d(TAG, "onDestroy: orientation=" + orientation());
        super.onDestroy();
    }

    String orientation(){
        return getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE ?  "Landscape" : "Portrait";
    }
}

build.gradle

android {
    compileSdkVersion 26
    defaultConfig {
        applicationId "android.example.com.orientationtest8_1"
        minSdkVersion 15
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

layout activity_main File:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="android.dermalog.com.orientationtest8_1.MainActivity">

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

And last a Log from clicking on Buttons repeatadly:

01-04 15:18:06.744  D/MainActivity: onCreate: savedInstanceState=null
01-04 15:18:06.847  D/MainActivity: onStart: orientation=Portrait
01-04 15:18:06.850  D/MainActivity: onResume: orientation=Portrait
01-04 15:18:14.036  D/MainActivity: onPause: orientation=Portrait
01-04 15:18:14.108  D/LandscapeActivity: onCreate: savedInstanceState=nullorientation=Landscape
01-04 15:18:14.139  D/LandscapeActivity: onStart: orientation=Landscape
01-04 15:18:14.141  D/LandscapeActivity: onResume: orientation=Landscape
01-04 15:18:14.217  D/MainActivity: onStop: orientation=Portrait
01-04 15:18:15.643  D/LandscapeActivity: onPause: orientation=Landscape
01-04 15:18:15.711  D/MainActivity: onActivityResult: orientation=Portrait
01-04 15:18:15.719  D/MainActivity: onStart: orientation=Portrait
01-04 15:18:15.720  D/MainActivity: onResume: orientation=Portrait
01-04 15:18:15.786  D/LandscapeActivity: onStop: orientation=Landscape
01-04 15:18:15.786  D/LandscapeActivity: onDestroy: orientation=Landscape
01-04 15:18:18.036  D/MainActivity: onPause: orientation=Portrait
01-04 15:18:18.097  D/LandscapeActivity: onCreate: savedInstanceState=nullorientation=Landscape
01-04 15:18:18.121  D/LandscapeActivity: onStart: orientation=Landscape
01-04 15:18:18.123  D/LandscapeActivity: onResume: orientation=Landscape
01-04 15:18:18.213  D/MainActivity: onStop: orientation=Portrait
01-04 15:18:19.505  D/LandscapeActivity: onPause: orientation=Landscape
01-04 15:18:19.564  D/MainActivity: onActivityResult: orientation=Portrait
01-04 15:18:19.569  D/MainActivity: onStart: orientation=Portrait
01-04 15:18:19.569  D/MainActivity: onResume: orientation=Portrait
01-04 15:18:19.639  D/LandscapeActivity: onStop: orientation=Landscape
01-04 15:18:19.640  D/LandscapeActivity: onDestroy: orientation=Landscape
01-04 15:18:20.102  D/MainActivity: onPause: orientation=Portrait
01-04 15:18:20.103  D/MainActivity: onStop: orientation=Portrait
01-04 15:18:20.104  D/MainActivity: onDestroy: orientation=Portrait
01-04 15:18:20.123  D/MainActivity: onCreate: savedInstanceState=Bundle[{android:viewHierarchyState=Bundle[{android:views={16908290=android.view.AbsSavedState$1@7ceec3, 2131165191=android.support.v7.widget.Toolbar$SavedState@3c34340, 2131165193=android.view.AbsSavedState$1@7ceec3, 2131165199=android.view.AbsSavedState$1@7ceec3, 2131165219=android.view.AbsSavedState$1@7ceec3, 2131165229=android.view.AbsSavedState$1@7ceec3}}], android:lastAutofillId=1073741823, android:fragments=android.app.FragmentManagerState@c215279}]
01-04 15:18:20.149  D/MainActivity: onStart: orientation=Landscape
01-04 15:18:20.152  D/MainActivity: onResume: orientation=Landscape
01-04 15:18:20.699  D/MainActivity: onPause: orientation=Landscape
01-04 15:18:20.701  D/MainActivity: onStop: orientation=Landscape
01-04 15:18:20.702  D/MainActivity: onDestroy: orientation=Landscape
01-04 15:18:20.718  D/MainActivity: onCreate: savedInstanceState=Bundle[{android:viewHierarchyState=Bundle[{android:views={16908290=android.view.AbsSavedState$1@7ceec3, 2131165191=android.support.v7.widget.Toolbar$SavedState@807af46, 2131165193=android.view.AbsSavedState$1@7ceec3, 2131165199=android.view.AbsSavedState$1@7ceec3, 2131165219=android.view.AbsSavedState$1@7ceec3, 2131165229=android.view.AbsSavedState$1@7ceec3}}], android:lastAutofillId=1073741823, android:fragments=android.app.FragmentManagerState@8d12507}]
01-04 15:18:20.748  D/MainActivity: onStart: orientation=Portrait
01-04 15:18:20.751  D/MainActivity: onResume: orientation=Portrait
Rafael T
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3 Answers3

4

This bug was fixed. So waiting for next release/patch.

CeH9
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4

Yes, This is an issue in Android 8.1 OS version. As this was made obsolete. we can have a work around for these kind of issues. In this particular API level , Android OS might be storing the latest orientation value and is being applied to all the screens until the previous screen or that particular screen is destroyed. So, the work around for this type of issue is to change the orientation before going back to the screen .
for ex:

If ScreenA is in portrait mode and screenB is in landscape mode and if screen is moved to ScreenB which is Landscape and if you come back to ScreenA without killing ScreenB (restoring ScreenA), screenA also be visible in Landscape.
To fix this issue, force change the orientation of ScreenA to Portrait in onPause() or OnStop() of ScreenB(to restore ScreenA).

 if (android.os.Build.VERSION.SDK_INT >= 27) {
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}

after this call, ScreenA will be in portrait. Also, in onResume() of ScreenB,

if (android.os.Build.VERSION.SDK_INT >= 27) {
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
}
Rushi Ayyappa
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  • What about in screen which we have no control? Like going to email or sharing text in social media. We have no control in the code of those apps – Abu Saad Papa Oct 11 '18 at 07:51
  • @Pops this issue will be caused only if screenA's orientation is different to ScreenB and both should be restricted to single type. i.e eitehr portrait or landscape. In your question, if screen moves out of your app, nothing might happen. – Rushi Ayyappa Oct 11 '18 at 09:58
  • Imagine all my screens are in landscape orientation and we have a button for sharing our message in the app. When we tap the button to go to message app/whatsapp and change the phone to portrait mode, now the message app will be in portrait mode. When we come back to our app the landscape screen will be shown in portrait and we can't fix this issue with your solution above. – Abu Saad Papa Oct 11 '18 at 10:16
  • Yes. I faced the same issue. But this is the solution we can get . this worked for me. can you post your code. will check – Rushi Ayyappa Oct 11 '18 at 12:17
2

This might indeed be a framework bug. I noticed similar behavior on Samsung devices while using the camera app (via Intent) in landscape from a portrait-only app. I couldn't figure out what exactly the cause is, but I found a work-around that minimizes the effect.

If you tell the system you want to handle the orientation change yourself, by adding android:configChanges="orientation|screenSize" to your Activity, it won't be recreated on orientation change. Thus you can avoid the overhead of recreating the Activity (twice), which may improve the performance up to the point that you don't notice the orientation change at all.

<activity android:name=".MainActivity"
    android:screenOrientation="portrait"
    android:configChanges="orientation|screenSize">
Floern
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  • Hey, In my original app I'm using a camera in landscape too, thats why I wrote the sample above to make shure it has nothing to do with it. Regarding your `configChanges`: I tried it in my sample, but got still the same behavior. I will edit it in my original question to prevent others trying it – Rafael T Jan 04 '18 at 14:46
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    Does the activity still get recreated on orientation change? If so it might be another instance of the same Activity class. NB my Activity has `android:launchMode="singleTask"`, but I don't think that has an effect on this.. – Floern Jan 04 '18 at 15:23
  • exactly! I also played with launchMode `singleTask`, `singleTop` and `singleInstance` without any change. Note that this happens on 8.1 devices ONLY. If it IS a framework bug, how to get it confirmed? – Rafael T Jan 04 '18 at 15:26
  • Do you guys get any help ? – Ahmad Arslan Jun 27 '18 at 05:54