Android cannot set screenOrientation, - android-activity

Question

I have read through every post I could find on this and other sites and followed the advice, but in the most simple implementation I cannot get the Note 5 to set to Portrait mode when it is physically in Landscape orientation.
I added the lines as recommended to the manifest file, rebuilt and the app starts in Landscape mode.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.twistlogic.miwidget">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:configChanges="orientation"
android:screenOrientation="portrait"
android:theme="#style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
I also tried doing this with code, which is my main purpose:
this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_NOSENSOR);
this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
nothing is produced that works.
I am trying to learn Android so I understand this may well be due to my limited knowledge. What I am trying to do is fix the orientation and lock it there, then allow it to change only when the user pushes a button. I did read that the screen size had to be set after API 13. But I am not certain how to do so. I am using a fragment template screen from the basic activities when the project was created.
Thanks for any help.

Answer 1

This can be set in the Main Activity I have not tried to set it in the Manifest here is a single line of code and a few lines to write a test Ok here is the Manifest code at the end
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
int orientation = getResources().getConfiguration().orientation;
if(orientation == Configuration.ORIENTATION_PORTRAIT){
}else if(orientation == Configuration.ORIENTATION_LANDSCAPE){}
In your manifest file after your main activity Paste below line.
android:screenOrientation="portrait"
I have not tested this code in a Manifest file