Android应用程序定位问题

Question

我正在使用android studio进行项目。我已将website转换为android application。在android application我从vertical to horizontal mode更改Android手机的方向时，我的应用gets reloaded from the first page.

下面给出了android应用程序代码。

activity_main.xml

<?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="com.example.nandha.firstproject.MainActivity">

    <WebView
        android:id="@+id/myWebView"
        android:layout_width="368dp"
        android:layout_height="495dp"
        tools:layout_editor_absoluteX="8dp"
        tools:layout_editor_absoluteY="8dp" />

</android.support.constraint.ConstraintLayout>

MainActivity.java

package com.example.nandha.firstproject;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {
    private WebView myWebView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        myWebView = (WebView) findViewById(R.id.myWebView);
        WebSettings webSettings = myWebView.getSettings();
        webSettings.setJavaScriptCanOpenWindowsAutomatically(true);
        myWebView.loadUrl("http://192.168.43.75/login.php");
        myWebView.setWebViewClient(new WebViewClient());
    }

    @Override
    public void onBackPressed() {
        if (myWebView.canGoBack()) {
            myWebView.goBack();
        } else {
            super.onBackPressed();
        }
    }
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.nandha.firstproject">
    <uses-permission android:name="android.permission.INTERNET"></uses-permission>

    <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">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

</manifest>

When I change my orientation to horizontal mode it gets reloaded as shown below from the first page

Now, I need only the page in horizontal mode for which I changed to horizontal orientation and not from the previous page. 我的问题是I change the orientation to horizontal mode only for 2nd page. But, my application gets reloaded from 1st page in horizontal orientation

请帮助我解决这个问题。