自动更改活动：Android中的横向和纵向模式

Question

I have two activities in my Android app. On click I can move from one activity to another, back and forth. But when I am changing from landscape to portrait mode and vice versa, my activity is getting changed automatically which I did not expect. I expect it to remain on the same activity even if it is changed to portrait or landscape mode. So what might be the problem?

Update

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.dmacs.myapplication">

    <application
        android:allowBackup="true"
        android:icon="@drawable/icon1"
        android:label="@string/app_name"
        android:logo="@drawable/icon2"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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


        <activity android:name=".second_main">
        </activity><!-- ATTENTION: This was auto-generated to add Google Play services to your project for
     App Indexing.  See https://g.co/AppIndexing/AndroidStudio for more information. -->
        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@integer/google_play_services_version" />


    </application>

</manifest>

Answer 1

<activity
    android:name=".MainActivity"
    android:screenOrientation="sensor" 
    android:configChanges="orientation"
    android:label="@string/app_name"
    android:theme="@style/AppTheme.NoActionBar">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />

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

I simply added this line: android:screenOrientation="sensor"

It overrides the system(if your system can lock orientation)

Also add this line: android:configChanges="orientation"

It prevents any updates from occuring triggered by the orientation