Phonegap on Android: Why does triggering the backbutton cause a SocketException?

Question

I created an Android App with Phonegap.

Within my JavaScript code I do:

window.location.href = "http://m.facebook.com/dialog/" + params;

.. because I want to redirect to Facebook. That works good so far but when I press the back button of the Android device the app shows a popup with error message:

Application Error
A network error occured. (file:///android_asset//www/index.html#article?id=61142746)

So I checked the logs and this is what's being printed when I go to the Facebook page:

11-30 16:50:25.480: I/PRIME(12998): <CallBackProxy> Send to WebViewClient.
11-30 16:50:25.480: D/CordovaWebView(12998): >>> loadUrl(http://m.facebook.com/dialog/feed?app_id=408479945865356&link=http://nachrichten.mydomain.de/obama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille/id_61142746/index&picture=http://mcp.mydomain.de/images/id_61143440/af_amp/bilder/uno-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg&name=Skandalkandidatin%20bringt%20Obama%20in%20die%20Bredouille%0A&caption=mydomain.de%20Nachrichten&description=Skandalkandidatin%20bringt%20Obama%20in%20die%20Bredouille%0A...&redirect_uri=http://nachrichten.mydomain.de/obama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille/id_61142746/index)
11-30 16:50:25.490: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:25.620: W/webcore(12998): [webViewCore::webkitDraw] defer message ====
11-30 16:50:25.640: W/System.err(12998): java.net.SocketException: Socket closed
11-30 16:50:25.640: W/System.err(12998):    at libcore.io.Posix.accept(Native Method)
11-30 16:50:25.640: W/System.err(12998):    at libcore.io.BlockGuardOs.accept(BlockGuardOs.java:55)
11-30 16:50:25.640: W/System.err(12998):    at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:98)
11-30 16:50:25.640: W/System.err(12998):    at java.net.ServerSocket.implAccept(ServerSocket.java:202)
11-30 16:50:25.640: W/System.err(12998):    at java.net.ServerSocket.accept(ServerSocket.java:127)
11-30 16:50:25.640: W/System.err(12998):    at org.apache.cordova.CallbackServer.run(CallbackServer.java:195)
11-30 16:50:25.640: W/System.err(12998):    at java.lang.Thread.run(Thread.java:864)
11-30 16:50:25.650: D/DroidGap(12998): onMessage(onPageStarted,http://m.facebook.com/dialog/feed?app_id=408479945865356&link=http://nachrichten.mydomain.de/obama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille/id_61142746/index&picture=http://mcp.mydomain.de/images/id_61143440/af_amp/bilder/uno-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg&name=Skandalkandidatin%20bringt%20Obama%20in%20die%20Bredouille%0A&caption=mydomain.de%20Nachrichten&description=Skandalkandidatin%20bringt%20Obama%20in%20die%20Bredouille%0A...&redirect_uri=http://nachrichten.mydomain.de/obama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille/id_61142746/index)
11-30 16:50:25.830: I/PRIME(12998): <CallBackProxy> Send to WebViewClient.
11-30 16:50:25.830: D/CordovaWebView(12998): >>> loadUrl(http://m.facebook.com/login.php?app_id=408479945865356&skip_api_login=1&cancel=http%3A%2F%2Fnachrichten.mydomain.de%2Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%2Fid_61142746%2Findex&next=http%3A%2F%2Fm.facebook.com%2Fdialog%2Ffeed%3F_path%3Dfeed%26app_id%3D408479945865356%26redirect_uri%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26display%3Dtouch%26link%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26picture%3Dhttp%253A%252F%252Fmcp.mydomain.de%252Fimages%252Fid_61143440%252Faf_amp%252Fbilder%252Funo-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg%26name%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A%26caption%3Dmydomain.de%2BNachrichten%26description%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A...%26from_login%3D1%26client_id%3D408479945865356&rcount=1&_rdr)
11-30 16:50:25.830: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:25.830: D/skia(12998): notifyPluginsOnFrameLoad not postponed
11-30 16:50:25.830: D/Cordova(12998): onPageFinished(http://m.facebook.com/login.php?app_id=408479945865356&skip_api_login=1&cancel=http%3A%2F%2Fnachrichten.mydomain.de%2Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%2Fid_61142746%2Findex&next=http%3A%2F%2Fm.facebook.com%2Fdialog%2Ffeed%3F_path%3Dfeed%26app_id%3D408479945865356%26redirect_uri%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26display%3Dtouch%26link%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26picture%3Dhttp%253A%252F%252Fmcp.mydomain.de%252Fimages%252Fid_61143440%252Faf_amp%252Fbilder%252Funo-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg%26name%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A%26caption%3Dmydomain.de%2BNachrichten%26description%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A...%26from_login%3D1%26client_id%3D408479945865356&rcount=1&_rdr)
11-30 16:50:25.830: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:25.830: D/DroidGap(12998): onMessage(onNativeReady,null)
11-30 16:50:25.830: D/DroidGap(12998): onMessage(onPageFinished,http://m.facebook.com/login.php?app_id=408479945865356&skip_api_login=1&cancel=http%3A%2F%2Fnachrichten.mydomain.de%2Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%2Fid_61142746%2Findex&next=http%3A%2F%2Fm.facebook.com%2Fdialog%2Ffeed%3F_path%3Dfeed%26app_id%3D408479945865356%26redirect_uri%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26display%3Dtouch%26link%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26picture%3Dhttp%253A%252F%252Fmcp.mydomain.de%252Fimages%252Fid_61143440%252Faf_amp%252Fbilder%252Funo-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg%26name%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A%26caption%3Dmydomain.de%2BNachrichten%26description%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A...%26from_login%3D1%26client_id%3D408479945865356&rcount=1&_rdr)
11-30 16:50:25.840: D/DroidGap(12998): onMessage(onPageStarted,http://m.facebook.com/login.php?app_id=408479945865356&skip_api_login=1&cancel=http%3A%2F%2Fnachrichten.mydomain.de%2Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%2Fid_61142746%2Findex&next=http%3A%2F%2Fm.facebook.com%2Fdialog%2Ffeed%3F_path%3Dfeed%26app_id%3D408479945865356%26redirect_uri%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26display%3Dtouch%26link%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26picture%3Dhttp%253A%252F%252Fmcp.mydomain.de%252Fimages%252Fid_61143440%252Faf_amp%252Fbilder%252Funo-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg%26name%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A%26caption%3Dmydomain.de%2BNachrichten%26description%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A...%26from_login%3D1%26client_id%3D408479945865356&rcount=1&_rdr)
11-30 16:50:26.670: D/skia(12998): notifyPluginsOnFrameLoad not postponed
11-30 16:50:26.680: D/Cordova(12998): onPageFinished(http://m.facebook.com/login.php?app_id=408479945865356&skip_api_login=1&cancel=http%3A%2F%2Fnachrichten.mydomain.de%2Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%2Fid_61142746%2Findex&next=http%3A%2F%2Fm.facebook.com%2Fdialog%2Ffeed%3F_path%3Dfeed%26app_id%3D408479945865356%26redirect_uri%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26display%3Dtouch%26link%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26picture%3Dhttp%253A%252F%252Fmcp.mydomain.de%252Fimages%252Fid_61143440%252Faf_amp%252Fbilder%252Funo-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg%26name%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A%26caption%3Dmydomain.de%2BNachrichten%26description%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A...%26from_login%3D1%26client_id%3D408479945865356&rcount=1&_rdr)
11-30 16:50:26.680: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:26.680: D/DroidGap(12998): onMessage(onNativeReady,null)
11-30 16:50:26.680: D/DroidGap(12998): onMessage(onPageFinished,http://m.facebook.com/login.php?app_id=408479945865356&skip_api_login=1&cancel=http%3A%2F%2Fnachrichten.mydomain.de%2Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%2Fid_61142746%2Findex&next=http%3A%2F%2Fm.facebook.com%2Fdialog%2Ffeed%3F_path%3Dfeed%26app_id%3D408479945865356%26redirect_uri%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26display%3Dtouch%26link%3Dhttp%253A%252F%252Fnachrichten.mydomain.de%252Fobama-geraet-wegen-seiner-personalpolitik-weiter-in-bredouille%252Fid_61142746%252Findex%26picture%3Dhttp%253A%252F%252Fmcp.mydomain.de%252Fimages%252Fid_61143440%252Faf_amp%252Fbilder%252Funo-botschafterin-und-obama-vertraute-susan-rice-unter-beschuss.jpg%26name%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A%26caption%3Dmydomain.de%2BNachrichten%26description%3DSkandalkandidatin%2Bbringt%2BObama%2Bin%2Bdie%2BBredouille%250A...%26from_login%3D1%26client_id%3D408479945865356&rcount=1&_rdr)
11-30 16:50:26.840: D/SQLiteDatabase(12998): Create pool connection
11-30 16:50:26.840: D/SqliteDatabaseCpp(12998): DB info: open db, path = /data/data/de.mydomain2.my_place_de/databases , key = sefraes, flag = 1, file size = 12288
11-30 16:50:26.840: D/SqliteDatabaseCpp(12998): DB info: path = /data/data/de.mydomain2.my_place_de/databases , key = sefraes, handle: 0xb14f98, type: r, r/w: (1,1), mode: wal, disk free size: 1753 M
11-30 16:50:26.890: I/SqliteDatabaseCpp(12998): sqlite returned: error code = 1, msg = no such table: __version__

And this is what the logs say when I press the back button:

11-30 16:50:52.210: D/CordovaWebView(12998): >>> loadUrl(file:///android_asset/www/index.html#article?id=61142746)
11-30 16:50:52.210: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:52.220: D/chromium(12998): Unknown chromium error: -6
11-30 16:50:52.220: D/DroidGap(12998): onMessage(onPageStarted,file:///android_asset/www/index.html#article?id=61142746)
11-30 16:50:52.230: D/Cordova(12998): CordovaWebViewClient.onReceivedError: Error code=-1 Description=Es ist ein Netzwerkfehler aufgetreten. URL=file:///android_asset/www/index.html#article?id=61142746
11-30 16:50:52.230: D/DroidGap(12998): onMessage(onReceivedError,{"errorCode":-1,"url":"file:\/\/\/android_asset\/www\/index.html#article?id=61142746","description":"Es ist ein Netzwerkfehler aufgetreten."})
11-30 16:50:52.320: D/skia(12998): notifyPluginsOnFrameLoad not postponed
11-30 16:50:52.350: W/System.err(12998): java.net.SocketException: Socket closed
11-30 16:50:52.350: W/System.err(12998):    at libcore.io.Posix.accept(Native Method)
11-30 16:50:52.350: W/System.err(12998):    at libcore.io.BlockGuardOs.accept(BlockGuardOs.java:55)
11-30 16:50:52.350: W/System.err(12998):    at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:98)
11-30 16:50:52.350: W/System.err(12998):    at java.net.ServerSocket.implAccept(ServerSocket.java:202)
11-30 16:50:52.350: W/System.err(12998):    at java.net.ServerSocket.accept(ServerSocket.java:127)
11-30 16:50:52.360: W/System.err(12998):    at org.apache.cordova.CallbackServer.run(CallbackServer.java:195)
11-30 16:50:52.360: W/System.err(12998):    at java.lang.Thread.run(Thread.java:864)
11-30 16:50:52.360: D/DroidGap(12998): onMessage(onPageStarted,file:///android_asset/www/index.html#article?id=61142746)
11-30 16:50:52.360: D/Cordova(12998): onPageFinished(file:///android_asset/www/index.html#article?id=61142746)
11-30 16:50:52.360: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:52.370: D/DroidGap(12998): onMessage(onNativeReady,null)
11-30 16:50:52.370: D/DroidGap(12998): onMessage(onPageFinished,file:///android_asset/www/index.html#article?id=61142746)
11-30 16:50:52.370: D/SoftKeyboardDetect(12998): Ignore this event
11-30 16:50:52.390: D/Cordova(12998): onPageFinished(file:///android_asset/www/index.html#article?id=61142746)
11-30 16:50:52.390: D/CordovaWebView(12998): >>> loadUrlNow()
11-30 16:50:52.390: D/DroidGap(12998): onMessage(onNativeReady,null)
11-30 16:50:52.390: D/DroidGap(12998): onMessage(onPageFinished,file:///android_asset/www/index.html#article?id=61142746)

What's going on?

---

Note: This only happens on these devices.

• HTC One
• Samsung Galaxy Note

It does NOT happen on:

• HTC Sensation
• Samsung Galaxy S2
• Samsung Galaxy S3

Answer 1

The back button closes the app and that means the CallbackServer is shut down breaking the socket and that is what fires the exception. However, you will only see this on some phones as not all JavaScript/native communication takes place via the CallbackServer. We pick the best method available depending on what the phone is capable of.

Also, if you upgrade to PhoneGap 2.2.0 you'll never see that exception again as we've retired the CallbackServer.