Develop Reference

Landscape layout file is loaded, while portrait mode is forced. (Android)

I'm currently developing an app, in which phones have forced portrait mode, while tablets support portrait mode as well as landscape mode. Some pages the layouts have respective landscape versions in the layout-land folder.
The problem
While using the app on a phone (so portrait only) and when autorotate on the phone is enabled, the landscape layout file gets loaded while the app is displayed as portrait mode.
When does this occur
To recreate this behaviour I open an activity and rotate the device. Then when I navigate to another activity, or close and open the application, the landscape layout gets loaded.
Method of forcing portrait mode
To force portrait mode on phones, I call
setRequestedOrientation (ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
in my BaseActivity onCreate method.
Other details
targetSdkVersion: 26
using support library 26.0.0
Thank you for helping!
Edit 1:
Unfortunately using (a combination of) the following settings in the manifest file gives the same behaviour.
android:screenOrientation="sensorPortrait"
android:screenOrientation="portrait"
android:configChanges="orientation"
Edit 2:
I've now tested on multiple devices (emulator, One plus, Motorola, Samsung and some more) and this oddity only happens on a Samsung A5 (api 23) for me.

Is other Activities are also have that code?
I meant, other Activity that doesn't extends BaseActivity?
I would prefer to set in AndroidManifest.xml file in each activity tag like >> android:screenOrientation="portrait"

add this line android:screenOrientation="portrait" in your project manifest file inside activity. Hope it work well.

Try this
<activity
android:name=".Activity"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="#string/title_activity_test_edit"
android:screenOrientation="sensorPortrait"
android:theme="#style/Theme.DesignDemo"
android:windowSoftInputMode="stateAlwaysHidden" />
Portrait orientation, but can be either normal or reverse portrait based on the device sensor.
Refer this link for more details :
https://developer.android.com/guide/topics/manifest/activity-element.html

As you mentioned,
phones have forced portrait mode, while tablets support portrait mode
as well as landscape mode
Set screen orientation in manifest will not work.
Use layout-land-sw600dp, layout-land-sw720dp folders for landscape view for tablets. Also please take a look at this SO thread

Android Studio - landscape only but still rotate

I want my android studio app to be landscape only, but to switch orientation when the phone is rotated.
This means that when u flip the phone 180°, it will still be landscape but will flip sides. Like the clash of clans game.

You should add the sensorLandscape screenOrientation tag to your activity in the android manifest file and you should be good to go.
android:screenOrientation="sensorLandscape"
Make sure to add this to all the activities that you want to have in landscape mode.

All you need is to go to your AndroidManifest.xml file and under each Activity add the screen orientation tag and set it to sensorLandscape. Make sure you do it for all the other activities if you want them to be in landscape too.
For Example :
<activity
android:name=".MainActivity"
android:label="#string/title_MainActivity"
android:screenOrientation="sensorLandscape">
</activity>

Troubleshoot orientation changing issue

In one of my application, there are multiple Activity(s),
Mostly all activities are configured to be in Landscape orientation by providing android:screenOrientation="sensorLandscape" for each activity
in android manifest file. But one of the activity called 'MyDashBoardActivity' changes orientation to Portrait automatically, when that Activity starts in one of my Android device, but it works fine (Loads in Landscape orientation as expected) in other devices.
How can troubleshoot this issue.

remove this android:screenOrientation="sensorLandscape"
And write In your onCreate :
after setContentView();
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

Try myActivity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
or
<activity android:screenOrientation="landscape" android:configChanges="orientation|keyboardHidden" android:name="MyDashBoardActivity"/>

Android ScreenOrientation behavior

I got an activity which I want to always remain with portrait layout. I got these settings in the manifest file:
<activity android:name="Main"
android:launchMode="singleInstance"
android:label="#string/app_name" android:screenOrientation="portrait" android:configChanges="keyboardHidden|orientation" android:windowSoftInputMode="stateAlwaysHidden|adjustNothing">
This settings makes the activity just load the portrait layout to the side if I turn the device on the side. I want the layout to just remain in the portrait position and that's it even though it means viewing the layout on the side when switching the device 90 degrees.

From Android 3.2 onwards, you also need to add screenSize to configChanges
android:screenOrientation="portrait"
android:configChanges="keyboardHidden|orientation|screenSize"
From the developer docs at handling runtime changes
Caution: Beginning with Android 3.2 (API level 13), the "screen size" also changes when the device switches between portrait and landscape orientation.

Force it dynamically:
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);

Set orientation - native camera/maps some other apps too

I am developing an application to take photos using the Android native camera and load maps, etc.
The orientation of the maps has been changing as I change it, but what I actually need is to have only landscape orientation even on native apps since my whole application is landscape-only.
But how can I set the orientation?

In the AndroidManifest.xml file you specify the acceptable orientations for your application.
To force your activity to remain in landscape mode simply include the android:screenOrientation tag in your activity's definition tag.
<activity android:name=".SomeActivity"
android:label="#string/app_name"
android:screenOrientation="landscape">