Android app - using AsyncTask - stops opening a URL in WebView, it is opened by the default browser if I call another URL - browser

Question

I'm beginning to develop in android using the material from http://developer.android.com.
I took one of their examples and modified it, so that my application can connect to a webpage. It works well when it is opened but if I click on an actionBar item which should open another page the new page isn't opened in the WebView, but it's launched the default browser.
I tried in many way to understand how to avoid that, but my little experience didn't allow me to fixe the problem.
Can you help me?
Many thanks.
Nino
public class MainActivity extends Activity {
public static final String WIFI = "Wi-Fi";
public static final String ANY = "Any";
public static String PAGINA ="http://www.kibao.org/simu/wap.php?lng=";
public static String BASE ="http://www.kibao.org";
public static String ATTUALE ="";
public static String lng = "";
final Context context = this;
private static boolean wifiConnected = false;
private static boolean mobileConnected = false;
public static boolean refreshDisplay = true;
public static String sPref = null;
public static String pagina = "";
private NetworkReceiver receiver = new NetworkReceiver();
#Override
public void onCreate(Bundle savedInstanceState) {
lng = getResources().getString(R.string.lng);
IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
receiver = new NetworkReceiver();
this.registerReceiver(receiver, filter);
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
#Override
public void onStart() {
super.onStart();
SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);
sPref = sharedPrefs.getString("listPref", "Wi-Fi");
updateConnectedFlags();
if (refreshDisplay) {
ATTUALE=PAGINA.concat(lng);
loadPage(ATTUALE);
}
}
#Override
public void onDestroy() {
super.onStop();
String ciao = getResources().getString(R.string.ciao);
show_toast(ciao);
if (receiver != null) {
this.unregisterReceiver(receiver);
}
}
private void updateConnectedFlags() {
ConnectivityManager connMgr =
(ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeInfo = connMgr.getActiveNetworkInfo();
if (activeInfo != null && activeInfo.isConnected()) {
wifiConnected = activeInfo.getType() == ConnectivityManager.TYPE_WIFI;
mobileConnected = activeInfo.getType() == ConnectivityManager.TYPE_MOBILE;
} else {
wifiConnected = false;
mobileConnected = false;
}
}
private void loadPage(String pgUrl) {
if (((sPref.equals(ANY)) && (wifiConnected || mobileConnected))
|| ((sPref.equals(WIFI)) && (wifiConnected))) {
new DownloadWebpageTask().execute(pgUrl);
} else {
showErrorPage();
}
}
// Displays an error if the app is unable to load content.
private void showErrorPage() {
....
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.items, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.menu1:
if (refreshDisplay) {
ATTUALE=BASE.concat("/partite.php?lng=");
ATTUALE=ATTUALE.concat(lng);
loadPage(ATTUALE);
}
return true;
....
default:
return super.onOptionsItemSelected(item);
}
}
private InputStream downloadUrl(String urlString) throws IOException {
URL url = new URL(urlString);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000 /* milliseconds */);
conn.setConnectTimeout(15000 /* milliseconds */);
conn.setRequestMethod("GET");
conn.setDoInput(true);
conn.connect();
InputStream stream = conn.getInputStream();
return stream;
}
public class NetworkReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
ConnectivityManager connMgr =
(ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
if (WIFI.equals(sPref) && networkInfo != null
&& networkInfo.getType() == ConnectivityManager.TYPE_WIFI) {
refreshDisplay = true;
Toast.makeText(context, R.string.wifi_connected, Toast.LENGTH_SHORT).show();
} else if (ANY.equals(sPref) && networkInfo != null) {
refreshDisplay = true;
} else {
refreshDisplay = false;
Toast.makeText(context, R.string.lost_connection, Toast.LENGTH_SHORT).show();
}
}
}
private class DownloadWebpageTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
try {
return loadWebpageFromNetwork(urls[0]);
} catch (IOException e) {
return getResources().getString(R.string.connection_error);
}
}
#Override
protected void onPostExecute(String result) {
setContentView(R.layout.main);
WebView myWebView = (WebView) findViewById(R.id.webview);
myWebView.loadUrl(ATTUALE);
}
}
private String loadWebpageFromNetwork(String urlString) throws IOException {
InputStream stream = null;
try {
stream = downloadUrl(urlString);
pagina = getStringFromInputStream(stream);
} finally {
if (stream != null) {
stream.close();
}
}
return pagina;
}
private static String getStringFromInputStream(InputStream is) {
BufferedReader br = null;
StringBuilder sb = new StringBuilder();
String line;
try {
br = new BufferedReader(new InputStreamReader(is));
while ((line = br.readLine()) != null) {
sb.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (br != null) {
try {
br.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return sb.toString();
}
........
}

Answer 1

This DownloadWebpageTask tries to "download" a webpage into a string, using a webview. This is not the correct way to do it. You are using the wrong tutorial. Don't use AsyncTasks for this. Start all over, using this:
http://developer.android.com/reference/android/webkit/WebView.html
or
http://www.mkyong.com/android/android-webview-example/
Simply call webview.loadUrl(url) again with a different url if you want to load a different page. It's as simple as that.

Answer 2

I've found another solution that works. I added the line
myWebView.setWebViewClient(new WebViewClient());
in the onPostExecute:
protected void onPostExecute(String result) {
setContentView(R.layout.main);
WebView myWebView = (WebView) findViewById(R.id.webview);
myWebView.setWebViewClient(new WebViewClient());
myWebView.loadUrl(ATTUALE);
}
Thanks, Frank.
PS I've tried to add a comment to the last Frank's post, but I didn't succeed!