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
Open your device's Settings app. . Select Accessibility. Select Auto-rotate screen.
From Settings, tap Lock screen, and then tap Always On Display. Tap Screen orientation, and then tap Landscape. Now your Always On Display will always display in Landscape mode.
When you rotate your device and the screen changes orientation, Android usually destroys your application's existing Activities and Fragments and recreates them . Android does this so that your application can reload resources based on the new configuration.
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);
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With