title: Android WebView not loading second page from cache
body: <p>I have an Android app that simply houses a website. I would like the app to cache the pages of the website for offline use.</p>
  
  <p>I'm doing a simple test to see if the cache is working but unfortunately it is failing to load a page i have previously loaded in online mode, when offline. To make things clearer i load the following 2 pages when in online mode.</p>
  
  <pre><code>webView.loadUrl("http://www.bmimobile.co.uk/why-bmi.php", getHeaders());
  webView.loadUrl("http://www.bmimobile.co.uk/", getHeaders());
  </code></pre>
  
  <p>.</p>
  
  <p>I am hoping that the "why-bmi.php" page is loaded into the cache as well as the subsequent page <a href="http://www.bmimobile.co.uk/" rel="noreferrer">http://www.bmimobile.co.uk/</a>. The latter page has a link on it which refers to the first page. If i then come out of the app and turn the network adapter off then go back into the app the "<a href="http://www.bmimobile.co.uk/" rel="noreferrer">http://www.bmimobile.co.uk/</a>" page DOES display but when i click the "why-bmi" link that page DOES NOT display. I short toast message displays saying "error loading page".</p>
  
  <p>Can anyone tell me why the webview is not caching loaded page for later offline use?</p>
  
  <p>Here's the main activity and i've extended the Application object defining the appcachepath.</p>
  
  <p>Thanks in advance</p>
  
  <p>Matt</p>
  
  <pre><code>package uk.bmi.mobile;
  
  import java.io.File;
  import java.util.HashMap;
  import java.util.Map;
  import android.app.Activity;
  import android.content.Context;
  import android.net.ConnectivityManager;
  import android.net.NetworkInfo;
  import android.os.Bundle;
  import android.util.Log;
  import android.webkit.WebSettings;
  import android.webkit.WebView;
  import android.webkit.WebViewClient;
  
  
  
  public class MainActivity extends Activity {
  
  
      private WebView webView;
      private static final String TAG = MainActivity.class.getSimpleName();
      ApplicationExt bmiAppObj;
  
  
      //instruct server to set it's headers to make resources cachable
      private Map&lt;String, String&gt; getHeaders() {
          Map&lt;String, String&gt; headers = new HashMap&lt;String, String&gt;();
          headers.put("IS_ALEX_APP", "1");
          return headers;
      }
  
  
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
          Log.e(TAG, "in onCreate in mainactivity");
  
  
  
      }      //end of oncreate
  
  
      private boolean isNetworkAvailable() {
          ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
          NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
          return activeNetworkInfo != null;
      }
  
  
  
      @Override
      protected void onResume() {
          super.onResume();
  
          Log.e(TAG, "in onResume in mainactivity");
          webView = (WebView)findViewById(R.id.webView1);
          bmiAppObj = (ApplicationExt)getApplication();
  
  
          if(isNetworkAvailable() == true){
  
              webView.getSettings().setSupportZoom(true);
              webView.getSettings().setBuiltInZoomControls(true);
              webView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
              webView.setScrollbarFadingEnabled(true);
              webView.getSettings().setLoadsImagesAutomatically(true);
              webView.getSettings().setDomStorageEnabled(true);
              webView.getSettings().setAppCacheEnabled(true);
              // Set cache size to 8 mb by default. should be more than enough
              webView.getSettings().setAppCacheMaxSize(1024*1024*8);
              // This next one is crazy. It's the DEFAULT location for your app's cache
              // But it didn't work for me without this line.
              // UPDATE: no hardcoded path. Thanks to Kevin Hawkins
              String appCachePath = getApplicationContext().getCacheDir().getAbsolutePath();
              Log.e(TAG, "appCachePath = " + appCachePath);
              webView.getSettings().setAppCachePath(appCachePath);
              webView.getSettings().setAllowFileAccess(true);
  
              webView.getSettings().setJavaScriptEnabled(true);
  
              // Load the URLs inside the WebView, not in the external web browser
              webView.setWebViewClient(new WebViewClient());  
              webView.getSettings().setCacheMode(WebSettings.LOAD_DEFAULT);
  
  
              webView.loadUrl("http://www.bmimobile.co.uk/why-bmi.php", getHeaders());
              webView.loadUrl("http://www.bmimobile.co.uk/", getHeaders());
  
  
              }else{
  
                  webView.getSettings().setSupportZoom(true);
                  webView.getSettings().setBuiltInZoomControls(true);
                  webView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
                  webView.setScrollbarFadingEnabled(true);
                  webView.getSettings().setLoadsImagesAutomatically(true);
                  webView.getSettings().setDomStorageEnabled(true);
                  webView.getSettings().setAppCacheEnabled(true);
                  // Set cache size to 8 mb by default. should be more than enough
                  webView.getSettings().setAppCacheMaxSize(1024*1024*8);
                  // This next one is crazy. It's the DEFAULT location for your app's cache
                  // But it didn't work for me without this line.
                  // UPDATE: no hardcoded path. Thanks to Kevin Hawkins
                  String appCachePath = getApplicationContext().getCacheDir().getAbsolutePath();
                  Log.e(TAG, "appCachePath = " + appCachePath);
                  webView.getSettings().setAppCachePath(appCachePath);
                  webView.getSettings().setAllowFileAccess(true);
  
                  webView.getSettings().setJavaScriptEnabled(true);
  
  
  
                  // Load the URLs inside the WebView, not in the external web browser
                  webView.setWebViewClient(new WebViewClient());  
  
  
  
                  webView.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ONLY);
  
                  webView.loadUrl("http://www.bmimobile.co.uk/", getHeaders());
  
  
              }
  
  
      }
  
  
  
  
  
  
      @Override
      public File getCacheDir()
      {
          // NOTE: this method is used in Android 2.1
          Log.e(TAG, "getcachedir");
          return getApplicationContext().getCacheDir();
      }
  
      @Override
      protected void onSaveInstanceState(Bundle outState)
      {
          super.onSaveInstanceState(outState);
  
          // Save the state of the WebView
          webView.saveState(outState);
      }
  
      @Override
      protected void onRestoreInstanceState(Bundle savedInstanceState)
      {
          super.onRestoreInstanceState(savedInstanceState);
  
          // Restore the state of the WebView
          webView.restoreState(savedInstanceState);
      }
  
  
  
  }//end of mainActivity
  </code></pre>
  
  <p>.</p>
  
  <pre><code>package uk.bmi.mobile;
  
  import java.io.File;
  
  import android.app.Application;
  import android.os.Environment;
  import android.util.Log;
  
  public class ApplicationExt extends Application
  {
      private static final String TAG = ApplicationExt.class.getSimpleName();
      // NOTE: the content of this path will be deleted
      //       when the application is uninstalled (Android 2.2 and higher)
      protected File extStorageAppBasePath;
  
      protected File extStorageAppCachePath;
  
      Webservice webservice;
      BmiDB bmiDb;
  
      @Override
      public void onCreate()
      {
          super.onCreate();
           Log.e(TAG, "inside appext");
  
           webservice = new Webservice(this);
           bmiDb = new BmiDB(this);
          // Check if the external storage is writeable
          if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState()))
          {
  
              // Retrieve the base path for the application in the external storage
              File externalStorageDir = Environment.getExternalStorageDirectory();
  
              if (externalStorageDir != null)
              {
                  // {SD_PATH}/Android/data/com.devahead.androidwebviewcacheonsd
                  extStorageAppBasePath = new File(externalStorageDir.getAbsolutePath() +
                      File.separator + "Android" + File.separator + "data" +
                      File.separator + getPackageName());
              }
  
              if (extStorageAppBasePath != null)
              {
                  // {SD_PATH}/Android/data/com.devahead.androidwebviewcacheonsd/cache
                  extStorageAppCachePath = new File(extStorageAppBasePath.getAbsolutePath() +
                      File.separator + "cache");
  
                  boolean isCachePathAvailable = true;
  
                  if (!extStorageAppCachePath.exists())
                  {
                      // Create the cache path on the external storage
                      isCachePathAvailable = extStorageAppCachePath.mkdirs();
                  }
  
                  if (!isCachePathAvailable)
                  {
                      // Unable to create the cache path
                      extStorageAppCachePath = null;
                  }
              }
          }
      }//end of onCreate
  
      @Override
      public File getCacheDir()
      {
          // NOTE: this method is used in Android 2.2 and higher
  
          if (extStorageAppCachePath != null)
          {
              // Use the external storage for the cache
              Log.e(TAG, "extStorageAppCachePath = " + extStorageAppCachePath);
              return extStorageAppCachePath;
          }
          else
          {
              // /data/data/com.devahead.androidwebviewcacheonsd/cache
              return super.getCacheDir();
          }
      }
  }
  </code></pre>
  
  <p>.This is the logging when the app is first loaded in online mode</p>
  
  <pre><code>02-16 08:38:52.744: I/NONPRIME(8871): &lt;CallBackProxy&gt; Send to WebViewClient.
  02-16 08:38:56.314: D/skia(8871): ----- started: [1 325] http://www.bmimobile.co.uk/images/mobile/bg-index.png
  02-16 08:38:56.499: D/skia(8871): ----- started: [1 64] http://www.bmimobile.co.uk/CubeCore/modules/cubeMobile/images/bg-black-bar.png
  02-16 08:38:56.509: D/skia(8871): ----- started: [26 20] http://www.bmimobile.co.uk/images/mobile/home-icon.png
  02-16 08:38:56.529: D/skia(8871): ----- started: [275 189] http://www.bmimobile.co.uk/images/mobile/home-img.png
  02-16 08:38:56.549: D/skia(8871): ----- started: [320 450] http://www.bmimobile.co.uk/images/mobile/welcome/bg-welcome.jpg
  02-16 08:38:56.554: D/skia(8871): ----- started: [270 38] http://www.bmimobile.co.uk/images/mobile/welcome/next.png
  02-16 08:38:56.584: D/skia(8871): ----- started: [16 17] http://www.bmimobile.co.uk/images/mobile/why.png
  02-16 08:38:56.584: D/skia(8871): ----- started: [18 17] http://www.bmimobile.co.uk/images/mobile/services.png
  02-16 08:38:56.584: D/skia(8871): ----- started: [20 15] http://www.bmimobile.co.uk/images/mobile/visit.png
  02-16 08:38:56.589: D/skia(8871): ----- started: [20 15] http://www.bmimobile.co.uk/images/mobile/consultants.png
  02-16 08:38:56.589: D/skia(8871): ----- started: [13 19] http://www.bmimobile.co.uk/images/mobile/contact.png
  </code></pre>
  
  <p>.</p>
  
  <p>This is the logging when i've come out of the app turned off the network adapter then gone back into app in offline mode.</p>
  
  <pre><code>02-16 08:41:37.799: E/MainActivity(8871): in onResume in mainactivity
  02-16 08:41:37.804: E/ApplicationExt(8871): extStorageAppCachePath = /storage/sdcard0/Android/data/uk.bmi.mobile/cache
  02-16 08:41:37.804: E/MainActivity(8871): appCachePath = /storage/sdcard0/Android/data/uk.bmi.mobile/cache
  02-16 08:41:37.834: W/dalvikvm(8871): disableGcForExternalAlloc: false
  </code></pre>
  
  <p>[edit1]
  Actually on closer inspection of the logging, it seems to have changed when loaded in online mode. below is the logcat in omline mode. There seems to be a problem with the cache storage.</p>
  
  <pre><code>02-19 15:16:10.497: E/ApplicationExt(5467): inside appext
  02-19 15:16:10.687: E/ApplicationExt(5467): extStorageAppCachePath = /storage/sdcard0/Android/data/uk.bmi.mobile/cache
  02-19 15:16:10.722: E/MainActivity(5467): in onCreate in mainactivity
  02-19 15:16:10.727: E/MainActivity(5467): in onResume in mainactivity
  02-19 15:16:10.737: E/ApplicationExt(5467): extStorageAppCachePath = /storage/sdcard0/Android/data/uk.bmi.mobile/cache
  02-19 15:16:10.737: E/MainActivity(5467): appCachePath = /storage/sdcard0/Android/data/uk.bmi.mobile/cache
  02-19 15:16:10.792: E/(5467): file /data/data/com.nvidia.NvCPLSvc/files/driverlist.txt: not found!
  02-19 15:16:10.792: I/(5467): Attempting to load EGL implementation /system/lib//egl/libEGL_tegra_impl
  02-19 15:16:10.807: I/(5467): Loaded EGL implementation /system/lib//egl/libEGL_tegra_impl
  02-19 15:16:10.842: I/(5467): Loading GLESv2 implementation /system/lib//egl/libGLESv2_tegra_impl
  02-19 15:16:10.882: E/SQLiteLog(5467): (1) no such table: CacheGroups
  02-19 15:16:10.882: D/WebKit(5467): ERROR: 
  02-19 15:16:10.882: D/WebKit(5467): Application Cache Storage: failed to execute statement "DELETE FROM CacheGroups" error "no such table: CacheGroups"
  02-19 15:16:10.882: D/WebKit(5467): external/webkit/Source/WebCore/loader/appcache/ApplicationCacheStorage.cpp(558) : bool WebCore::ApplicationCacheStorage::executeSQLCommand(const WTF::String&amp;)
  02-19 15:16:10.882: E/SQLiteLog(5467): (1) no such table: Caches
  02-19 15:16:10.882: D/WebKit(5467): ERROR: 
  02-19 15:16:10.882: D/WebKit(5467): Application Cache Storage: failed to execute statement "DELETE FROM Caches" error "no such table: Caches"
  02-19 15:16:10.882: D/WebKit(5467): external/webkit/Source/WebCore/loader/appcache/ApplicationCacheStorage.cpp(558) : bool WebCore::ApplicationCacheStorage::executeSQLCommand(const WTF::String&amp;)
  02-19 15:16:10.882: E/SQLiteLog(5467): (1) no such table: Origins
  02-19 15:16:10.882: D/WebKit(5467): ERROR: 
  02-19 15:16:10.882: D/WebKit(5467): Application Cache Storage: failed to execute statement "DELETE FROM Origins" error "no such table: Origins"
  02-19 15:16:10.882: D/WebKit(5467): external/webkit/Source/WebCore/loader/appcache/ApplicationCacheStorage.cpp(558) : bool WebCore::ApplicationCacheStorage::executeSQLCommand(const WTF::String&amp;)
  02-19 15:16:10.882: E/SQLiteLog(5467): (1) no such table: DeletedCacheResources
  02-19 15:16:10.992: E/ApplicationExt(5467): extStorageAppCachePath = /storage/sdcard0/Android/data/uk.bmi.mobile/cache
  02-19 15:16:11.022: W/dalvikvm(5467): disableGcForExternalAlloc: false
  02-19 15:16:13.787: I/NONPRIME(5467): &lt;CallBackProxy&gt; Send to WebViewClient.
  02-19 15:16:21.427: D/skia(5467): ----- started: [1 325] http://www.bmimobile.co.uk/images/mobile/bg-index.png
  02-19 15:16:21.517: D/skia(5467): ----- started: [1 64] http://www.bmimobile.co.uk/CubeCore/modules/cubeMobile/images/bg-black-bar.png
  02-19 15:16:21.542: D/skia(5467): ----- started: [26 20] http://www.bmimobile.co.uk/images/mobile/home-icon.png
  02-19 15:16:21.577: D/skia(5467): ----- started: [275 189] http://www.bmimobile.co.uk/images/mobile/home-img.png
  02-19 15:16:21.597: D/skia(5467): ----- started: [270 38] http://www.bmimobile.co.uk/images/mobile/welcome/next.png
  02-19 15:16:21.677: D/skia(5467): ----- started: [16 17] http://www.bmimobile.co.uk/images/mobile/why.png
  02-19 15:16:21.677: D/skia(5467): ----- started: [20 15] http://www.bmimobile.co.uk/images/mobile/visit.png
  02-19 15:16:21.677: D/skia(5467): ----- started: [18 17] http://www.bmimobile.co.uk/images/mobile/services.png
  02-19 15:16:21.687: D/skia(5467): ----- started: [20 15] http://www.bmimobile.co.uk/images/mobile/consultants.png
  02-19 15:16:21.687: D/skia(5467): ----- started: [13 19] http://www.bmimobile.co.uk/images/mobile/contact.png
  02-19 15:16:21.692: D/skia(5467): ----- started: [320 450] http://www.bmimobile.co.uk/images/mobile/welcome/bg-welcome.jpg
  </code></pre>
  
  <p>.</p>
  
  <p>[notes]
  if i click on the why-bmi button when in online mode then come out of the app, turn the adapter off then click the why-bmi button again then it shows the "error loading page" message.</p>
  
  <p>If i however change to the following urls, my SO page is displayed. If i click the link to my bounty page(this page), then go offline, the SO page is display as you would expect but if you click the bounty link in offline mode then it DOES display. so there are differences between the SO site and the bmi site.</p>
  
  <pre><code>if(isNetworkAvailable() == true){
  
              webView.getSettings().setSupportZoom(true);
              webView.getSettings().setBuiltInZoomControls(true);
              webView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
              webView.setScrollbarFadingEnabled(true);
              webView.getSettings().setLoadsImagesAutomatically(true);
              webView.getSettings().setDomStorageEnabled(true);
              webView.getSettings().setAppCacheEnabled(true);
              // Set cache size to 8 mb by default. should be more than enough
              webView.getSettings().setAppCacheMaxSize(1024*1024*8);
              // This next one is crazy. It's the DEFAULT location for your app's cache
              // But it didn't work for me without this line.
              // UPDATE: no hardcoded path. Thanks to Kevin Hawkins
              String appCachePath = getApplicationContext().getCacheDir().getAbsolutePath();
              Log.e(TAG, "appCachePath = " + appCachePath);
              webView.getSettings().setAppCachePath(appCachePath);
              webView.getSettings().setAllowFileAccess(true);
  
              webView.getSettings().setJavaScriptEnabled(true);
  
              // Load the URLs inside the WebView, not in the external web browser
              webView.setWebViewClient(new WebViewClient());  
              webView.getSettings().setCacheMode(WebSettings.LOAD_DEFAULT);
  
  
              //webView.loadUrl("http://www.bmimobile.co.uk/why-bmi.php", getHeaders());
              //webView.loadUrl("http://www.bmimobile.co.uk/", getHeaders());
  
              webView.loadUrl("http://stackoverflow.com/users/532462/turtleboy?tab=bounties");
              webView.loadUrl("http://stackoverflow.com/users/532462/turtleboy");
              }else{
  
                  webView.getSettings().setSupportZoom(true);
                  webView.getSettings().setBuiltInZoomControls(true);
                  webView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
                  webView.setScrollbarFadingEnabled(true);
                  webView.getSettings().setLoadsImagesAutomatically(true);
                  webView.getSettings().setDomStorageEnabled(true);
                  webView.getSettings().setAppCacheEnabled(true);
                  // Set cache size to 8 mb by default. should be more than enough
                  webView.getSettings().setAppCacheMaxSize(1024*1024*8);
                  // This next one is crazy. It's the DEFAULT location for your app's cache
                  // But it didn't work for me without this line.
                  // UPDATE: no hardcoded path. Thanks to Kevin Hawkins
                  String appCachePath = getApplicationContext().getCacheDir().getAbsolutePath();
                  Log.e(TAG, "appCachePath = " + appCachePath);
                  webView.getSettings().setAppCachePath(appCachePath);
                  webView.getSettings().setAllowFileAccess(true);
  
                  webView.getSettings().setJavaScriptEnabled(true);
  
  
  
                  // Load the URLs inside the WebView, not in the external web browser
                  webView.setWebViewClient(new WebViewClient());  
  
  
  
                  webView.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ONLY);
  
                 // webView.loadUrl("http://www.bmimobile.co.uk/", getHeaders());
                  webView.loadUrl("http://stackoverflow.com/users/532462/turtleboy");
  
  
              }
  
  
      }
  </code></pre>
  
  <p>[edit2]</p>
  
  <pre><code>    &lt;?xml version="1.0" encoding="utf-8"?&gt;
      &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="uk.bmi.mobile"
          android:versionCode="5"
          android:versionName="1.0.4" &gt;
  
          &lt;!-- GCM requires Android SDK version 2.2 (API level &lt;img src="http://www.androidhive.info/wp-includes/images/smilies/icon_cool.gif" alt="8)" class="wp-smiley"&gt; or above. --&gt;
          &lt;uses-sdk
              android:minSdkVersion="8"
              android:targetSdkVersion="16" /&gt;
  
          &lt;!-- GCM connects to Internet Services. --&gt;
          &lt;uses-permission android:name="android.permission.INTERNET" /&gt;
  
          &lt;!-- GCM requires a Google account. --&gt;
          &lt;uses-permission android:name="android.permission.GET_ACCOUNTS" /&gt;
  
          &lt;!-- Keeps the processor from sleeping when a message is received. --&gt;
          &lt;uses-permission android:name="android.permission.WAKE_LOCK" /&gt;
  
          &lt;!-- Creates a custom permission so only this app can receive its messages. --&gt;
          &lt;permission
              android:name="uk.bmi.mobile.permission.C2D_MESSAGE"
              android:protectionLevel="signature" /&gt;
  
          &lt;uses-permission android:name="uk.bmi.mobile.permission.C2D_MESSAGE" /&gt;
  
          &lt;!-- This app has permission to register and receive data message. --&gt;
          &lt;uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" /&gt;
  
          &lt;!-- Network State Permissions to detect Internet status --&gt;
          &lt;uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /&gt;
  
          &lt;!-- Permission to vibrate --&gt;
          &lt;uses-permission android:name="android.permission.VIBRATE" /&gt;
  
      &lt;uses-permission android:name="android.permisson.ACCESS_WIFI_STATE"/&gt;
      &lt;uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/&gt;
  &lt;uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/&gt;
  
          &lt;!-- Main activity. --&gt;
          &lt;application
              android:icon="@drawable/bmi_icon"
              android:label="@string/app_name"
              android:name="uk.bmi.mobile.ApplicationExt" &gt;
              &lt;!-- Register Activity --&gt;
              &lt;activity
                  android:name=".RegisterActivity"
                  android:label="@string/app_name" &gt;
                  &lt;intent-filter&gt;
                      &lt;action android:name="android.intent.action.MAIN" /&gt;
  
                      &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
                  &lt;/intent-filter&gt;
              &lt;/activity&gt;
  
              &lt;!-- Main Activity --&gt;
              &lt;activity
                  android:name="uk.bmi.mobile.MainActivity"
                  android:configChanges="orientation|keyboardHidden"
                  android:label="@string/app_name"
                   android:screenOrientation="portrait" &gt;
              &lt;/activity&gt;
  
              &lt;receiver
                  android:name="com.google.android.gcm.GCMBroadcastReceiver"
                  android:permission="com.google.android.c2dm.permission.SEND" &gt;
                  &lt;intent-filter&gt;
  
                      &lt;!-- Receives the actual messages. --&gt;
                      &lt;action android:name="com.google.android.c2dm.intent.RECEIVE" /&gt;
                      &lt;!-- Receives the registration id. --&gt;
                      &lt;action android:name="com.google.android.c2dm.intent.REGISTRATION" /&gt;
  
                      &lt;category android:name="uk.bmi.mobile" /&gt;
                  &lt;/intent-filter&gt;
              &lt;/receiver&gt;
  
              &lt;service android:name="uk.bmi.mobile.GCMIntentService" /&gt;
          &lt;/application&gt;
  
      &lt;/manifest&gt;
  </code></pre>