Webview - How to stay on the current page on Rotate

Question

I developed a website for my entreprisee and I work almost exclusively with PHP

So the Java language (and android studio) is a really new for me. Despite this I have to create an APK to use the website (in order to block the android home on this site)

But when I turn the screen, the webview displays the homepage rather than the current page.

I did some research and I integrated what I saw here: Android - Preventing WebView reload on Rotate

But that does not work and I do not understand why I always come back on "Google.com"

MainActivity.java

package eu.test.chrome;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;

public class MainActivity extends AppCompatActivity {

    WebView webView;

    SwipeRefreshLayout swipe;
    ProgressBar progressBar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        progressBar = (ProgressBar) findViewById(R.id.awv_progressBar);
        swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
        LoadWeb();

        progressBar.setMax(100);
        progressBar.setProgress(1);


        swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
        swipe.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                webView.reload();
            }
        });


        webView.setWebChromeClient(new WebChromeClient() {
            public void onProgressChanged(WebView view, int progress) {
                progressBar.setProgress(progress);
            }
        });


        webView.setWebViewClient(new WebViewClient() {

            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                super.onPageStarted(view, url, favicon);
                progressBar.setVisibility(View.VISIBLE);
            }


            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
                webView.loadUrl("file:///android_asset/error.html");
            }


            public void onPageFinished(WebView view, String url) {
                //Don't show ProgressBar
                progressBar.setVisibility(View.GONE);
                //Hide the SwipeRefreshLayout
                swipe.setRefreshing(false);
            }

        });

    }


    /* I integrated what I saw here: https://stackoverflow.com/questions/12131025/android-preventing-webview-reload-on-rotate but that does not work
    @Override
    protected void onSaveInstanceState(Bundle outState )
    {
        super.onSaveInstanceState(outState);
        webView.saveState(outState);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState)
    {
        super.onRestoreInstanceState(savedInstanceState);
        webView.restoreState(savedInstanceState);
    }*/


    public void LoadWeb() {

        webView = (WebView) findViewById(R.id.webView);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.getSettings().setAppCacheEnabled(true);
        webView.loadUrl("https://www.google.com/");
        swipe.setRefreshing(true);
    }

    @Override
    public void onBackPressed() {

        if (webView.canGoBack()) {
            webView.goBack();
        } else {
            finish();
        }
    }

}

Activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:id="@+id/rel_parent"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <ProgressBar
        android:id="@+id/awv_progressBar"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="26dp"
        android:indeterminate="true" />


    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipe"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <WebView
            android:id="@+id/webView"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />

    </android.support.v4.widget.SwipeRefreshLayout>


</LinearLayout>

Manifest

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

    <application
        android:hardwareAccelerated="false"
        android:configChanges="orientation|screenSize" 
        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>

did you add this `android:configChanges="keyboard|keyboardHidden|orientation"` — AskNilesh, Dec 20 '17 at 09:55
On my Manifest I add this : android:configChanges="orientation|screenSize" — Rocstar, Dec 20 '17 at 09:56
I just modified my manifest file like you and it does not work ... — Rocstar, Dec 20 '17 at 10:00

theboringdeveloper · Answer 1 · 2017-12-20T10:48:20.923

In Order to Load the Url Before Rotation, you need to make some additions.

public class MainActivity extends AppCompatActivity {
WebView webView;

SwipeRefreshLayout swipe;
ProgressBar progressBar;

private final String CACHE_URL_KEY = "CACHE_URL";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    progressBar = (ProgressBar) findViewById(R.id.awv_progressBar);
    swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
    LoadWeb(savedInstanceState);

    progressBar.setMax(100);
    progressBar.setProgress(1);


    swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
    swipe.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
        @Override
        public void onRefresh() {
            webView.reload();
        }
    });


    webView.setWebChromeClient(new WebChromeClient() {
        public void onProgressChanged(WebView view, int progress) {
            progressBar.setProgress(progress);
        }
    });


    webView.setWebViewClient(new WebViewClient() {

        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);
            progressBar.setVisibility(View.VISIBLE);
        }


        public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
            webView.loadUrl("file:///android_asset/error.html");
        }


        public void onPageFinished(WebView view, String url) {
            //Don't show ProgressBar
            progressBar.setVisibility(View.GONE);
            //Hide the SwipeRefreshLayout
            swipe.setRefreshing(false);
        }

    });

}


@Override
protected void onSaveInstanceState(Bundle outState )
{
    outState.putString(CACHE_URL_KEY,webView.getUrl());
    super.onSaveInstanceState(outState);
}


public void LoadWeb(Bundle savedInstanceState) {

    webView = (WebView) findViewById(R.id.webView);
    webView.getSettings().setJavaScriptEnabled(true);
    webView.getSettings().setAppCacheEnabled(true);


    if (savedInstanceState != null) {
        String savedUrl = savedInstanceState.getString(CACHE_URL_KEY);
        webView.loadUrl(savedUrl);
    }else {
        webView.loadUrl("https://www.google.com/");
    }


    swipe.setRefreshing(true);
}

@Override
public void onBackPressed() {

    if (webView.canGoBack()) {
        webView.goBack();
    } else {
        finish();
    }
}

}

These are the Steps Made:

You need to Create a Key to identify the Saved URL

private final String CACHE_URL_KEY = "CACHE_URL";
You need to save the URL Each Time you rotate

@Override protected void onSaveInstanceState(Bundle outState ) { outState.putString(CACHE_URL_KEY,webView.getUrl()); super.onSaveInstanceState(outState); }
You Need to Check if There is a Rotation or not. If yes, savedInstanceState won't be null therefore retrieve the Url and load it. Else Load Default page

if (savedInstanceState != null) { String savedUrl = savedInstanceState.getString(CACHE_URL_KEY); webView.loadUrl(savedUrl); }else { webView.loadUrl("https://www.google.com/"); }
Also, Pass the saved state to LoadWeb method

score 1 · Answer 2 · answered Dec 20 '17 at 09:57

Create Method in Android like :

 @JavascriptInterface
 public boolean CallByMobApp(){
 return true;
}

Create Calling function in JavaScript :

$(window).load(function () {

IsCallByMobileApp = false;
try {
      IsCallByMobileApp = app.CallByMobApp();/*Is call by android app*/

} catch (e) {
    IsCallByMobileApp = false;
}
}

According to this method you can manage which page to be open.

score 1 · Answer 3 · answered Dec 20 '17 at 10:04

1

You call the method LoadWeb each time. You need to check if savedInstanceState == null then call LoadWeb. If savedInstanceState != null then don't call LoadWeb

answered Dec 20 '17 at 10:04

elgringo

73
6

I add this if (savedInstanceState == null) { LoadWeb(); } but it doesn't work – Rocstar Dec 20 '17 at 10:26

score 1 · Accepted Answer · answered Dec 20 '17 at 10:29

Try this

import android.graphics.Bitmap;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.view.View;

import android.support.v4.widget.SwipeRefreshLayout;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;

public class Main2Activity extends AppCompatActivity {

    WebView webView;

    SwipeRefreshLayout swipe;
    ProgressBar progressBar;
    Toolbar toolbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);



        LoadWeb();
        progressBar = (ProgressBar) findViewById(R.id.awv_progressBar);
        progressBar.setMax(100);
        progressBar.setProgress(1);


        swipe.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                webView.reload();
            }
        });

        webView.setWebChromeClient(new WebChromeClient() {
            public void onProgressChanged(WebView view, int progress) {


                progressBar.setProgress(progress);
            }
        });

        webView.setWebViewClient(new WebViewClient() {

            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                super.onPageStarted(view, url, favicon);
                progressBar.setVisibility(View.VISIBLE);
            }

            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {

                webView.loadUrl("https://stackoverflow.com/questions/47885592/how-to-add-a-progress-loading-bar-in-webview/47885692#47885692");
            }

            public void onLoadResource(WebView view, String url) { //Doesn't work
//                swipe.setRefreshing(true);
            }

            public void onPageFinished(WebView view, String url) {

                //Hide the SwipeReefreshLayout
                progressBar.setVisibility(View.GONE);
                swipe.setRefreshing(false);
            }

        });


    }

    public void LoadWeb() {

        swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
        webView = (WebView) findViewById(R.id.webView);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.getSettings().setAppCacheEnabled(true);
        webView.loadUrl("http://dev.ncryptedprojects.com/bistrostays_v3/");
        swipe.setRefreshing(true);
    }

    @Override
    protected void onSaveInstanceState(Bundle outState )
    {
        super.onSaveInstanceState(outState);
        webView.saveState(outState);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState)
    {
        super.onRestoreInstanceState(savedInstanceState);
        webView.restoreState(savedInstanceState);
    }

    @Override
    public void onBackPressed() {

        if (webView.canGoBack()) {
            webView.goBack();
        } else {
            finish();
        }
    }

}

and in your manifest file

<activity android:name=".MainActivity"
   android:configChanges="orientation|screenSize">
     <intent-filter>
       <action android:name="android.intent.action.MAIN" />

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

I copied pasted your code but I have this error message "Unfortunately, .. as stopped" — Rocstar, Dec 20 '17 at 11:01
It works ! the mistake came from the theme that I had not changed, thank you very much for your help ! — Rocstar, Dec 20 '17 at 11:26

Webview - How to stay on the current page on Rotate

4 Answers4