Every so often, my iPhone app gets into a state where network requests always time out, even if other apps work fine (and can even access the same sites). This isn't obviously correlated with changes in network availability, and happens both on 3G and over WiFi. Any suggestions on how to diagnose the problem?
(FWIW, the app uses MonoTouch and HttpWebRequest, but I suspect whatever's going wrong is lower-level.)
Note: The problem persists through backgrounding the app and changing the network configuration; the only fix seems to be to kill the app and re-launch it.
Updates: I've tried making use of Reachability, but to no effect. Reachability.InternetConnectionStatus always returns ReachableViaWiFiNetwork (or ReachableViaCarrierDataNetwork, depending; likewise IsHostReachable() always returns true. Runtime.StartWWAN() seems to make no difference.
There was a bug open about this at https://bugzilla.novell.com/show_bug.cgi?id=555439 and there were several attempts at resolving it. As of the last comment in the bug, it was presumed fixed but I guess if you are using MonoTouch 4.0.3 then there some cases that are not worked around.
Basically, the problem is reflected in this other Stackoverflow question: iPhone 3G Connection Enabling
What MonoTouch does to try and work around this issue is to call MonoTouch.Runtime.StartWWAN(Uri) which opens a dummy connection to the uri using an NSUrlConnection to force-wake the network interface. Then, MonoTouch goes back to using the BSD socket API inside the HttpWebRequest.
Try setting the timeOutInterval property of the NSURLRequest used to make the call.
Related
I got following error on google play store but I have no idea why this error occured. They said that it is happing on (Sharp AQUOS sense2 SH-01L Android 9 (SDK 28) ).
I have logcat but I can't find anything in logcat too. I already released to production. This one is my bugs fixed for new release.
ANR in com.google.android.apps.tachyon;PID: 18069;Broadcast of Intent {
act=android.accounts.LOGIN_ACCOUNTS_CHANGED flg=0x5000010 cmp=com.google.android.apps.tachyon/com.google.apps.tiktok.account.data.device.DeviceAccountsChangedReceiver_Receiver };
A similar Error occurred for me as well.
"ANR in com.google.android.apps.tachyon" at same device "Sharp AQUOS sense2 SH-01L"
E/ActivityManager(1566): ANR in com.google.android.apps.tachyon
E/ActivityManager(1566): PID: 18457
E/ActivityManager(1566): Reason: Broadcast of Intent { act=android.intent.action.LOCALE_CHANGED flg=0x11200010 cmp=com.google.android.apps.tachyon/.common.applifecycle.LocaleChangeReceiver }
I believe this device has com.google.android.apps.tachyon app is installed by default and an automatic update for this app could be running in the background (just a guess) which crashes anytime.
The crash is just a coincidence.
It will not happen every time with the same app and with the same use case. It will also not happen with any other device. just update the versionCode and publish the App again.
One other option is to go to the device catalog and mark this device as not supported.
After a lot of research, I think I have finally solved this for my app.
In my case, other than my main activity, the other Activies were only called by my app. In my activities in my AndroidManifest.xml, I had
android:exported="true"
Of course, this allows these activities to be invoked by other external activities/etc
By changing this to:
android:exported="false"
...it prevents the activity from being called.
In my case and going through the logs, I didn't see anything that jumped out and bit me but my research led me to believe that com.google.apps.tiktok.* was some sort of old transactional piece of Android. Also, I noticed my Tutorial activity was logging well after it should have been.
My suspicion is the test may actually be real and intended to check for either Activities handling external launches or checking for a security injection of some kind.
I think the use case is likely that an Android user is changed on the phone (usually at end of these robo tests), ticktok handles that and sends this intent/message to all externally known Activities. If so, that would mean either the Activities have to not be exported or handle the intent appropriately.
Anyhow, this change helped me tremendously and I haven't hit this with this app since after about 100 robo tests. Hope it helps someone else.
I think this is a problem with Google Play Store testing devices. Problems went away without me making any changes on a new release.
I am using a third party framework, which in rare cases does not respond anymore, if the internet connection is lost. My tests showed that when I am connected via WiFi on my home network and I start using the app and when the network changes from WiFi to the carrier network, the thread does not respond, if it was exchanging data at that very moment.
Of course I got in touch with the vendor of the framework to fix this, however, it will take some time, until I will get the patch.
In the meantime I would like to implement a work-around, so the user does not have to deal with a non-responding app, especially as this is a no-go for the app approval.
My question: Is there a way I can monitor such a thread and terminate it after a timeout?
Or would anyone have another solution approach for this issue? I know about the reachability framework of Apple, but as far as I understand the framework, it is a detection tool only, which in my case would not solve my issue, right?
Thanks, René
I'm having an issue that's incredibly hard to debug. If my app is using WiFi and it sits idle for around 30 minutes, sometimes when I wake it up, the NSURLConnection no longer responds. Requests are sent, but never return.
At first, I thought this was a memory bug with the instances being released too early and thus never returning a response. However, if I put the app in the background, go into settings, turn off WiFi so 3G is used exclusively, and return to the app, the internet connection magically comes back to life and all pending NSURLConnections return and complete.
Obviously this is an issue for people using WiFi. Is this really a WiFi issue, or am I missing something? Going to another app like Safari, using the WiFi radio and returning to my app doesn't solve the problem - connections still don't return. I've traced this with Xcode and I'm running out of ideas.
Also 'Application Uses WiFi' Info.plist flag is set to ON and this is firmware 5.1.
is 'Application Uses WiFi' the same as UIRequiresPersistentWiFi?
Update: This has nothing to do with the Wifi flag - it can die within 5 minutes. So far, I've only been able to duplicate it on my iPhone 4s with 5.1 firmware. It's not really a solution, but I'm erasing the phone to try it with a fresh install to see if that has any effect. I have verified that NSURLConnection is always called on the main thread, and set breakpoints at connection:failedWithError: and connection:didReceiveResponse:. When the connection dies, none of these return until I disable and re-enable WiFi, and then all return at once. This happens on a local server as well, and the server still returns if I ping it with a web browser.
For any others running into this issue, it's due to TestFlight v1.0 and below:
Why does NSURLConnection fail to reach the backend?
Are you actually transmitting/receiving any data through the NSURLConnection? If not, is it possible you are hitting a TCP session timeout? Seems unlikely if the problem persists on a local server, but any intervening stateful firewall/packet inspector might be casting off your TCP connection.
I have a app from where i hit different REST urls. one of the service is login service.
Now, do i have to use the apple rechability test everytime i want to make a connection?
I use ASIHttpRequest
No, ASIHTTPRequest will return a timeout error / a connection failure error if it can't reach the host. You can use those errors to show something to the user to tell them their login has failed.
The connectivity status of your mobile device can change very often and unforeseeably, so checking it often is advisable.
Say, for example, that you check at app startup, and find that not network is available. You go to offline mode, but then in a few minutes you could get in a WI-FI area or your 3G signal might be stronger. If you don't check it again, you lose the possibility of going to online mode.
Indeed, checking for network availability is pretty fast compared to how long a network request lasts (say: sending a login request and waiting for the response), so you can safely do the check whenever you need it according to your policy, be it at each request, every 5 minutes, or whatever.
EDIT:
about your concern as to the approval process: you should ensure that your app has a reasonable behavior when no connection it available. Simply showing an alert to the user (and not crashing) is enough for Apple, but you could also resort to disabling all your network related buttons, or whatever fits your app. The idea is that your app should not behave crazily when no connection is available.
If you want more advanced behavior, you can check reachability with each request.
You can also use the Reachability notification service (ASIHTTP-bundled Reachability includes that feature). You can find an how-to here. But in my opinion is a bit easier to just do the check when you need it. YMMV
From what I remember the reachability demo code is effectively a listener so can update a variable as the device's reachability state changes. You then need to check this variable before making a request.
Would be surprised ASIHTTP doesn't do this kind of thing already.
I have an iPhone app which communicates with a server to get the data being displayed. I have tested this app on a wifi connection and a good 3G connection. The app works without an issue. But if I test the app on a poor connection, the app crashes.
I get an XML from the server and parse it before displaying the data. I have put in the NSXMLParser method to show an alert if the parsing fails. The n/w connection code is also placed in try/catch blocks and we show an alert if the control goes to the catch block.
On a poor internet connection, the app just crashes (doesn't even go to the catch block) and checking the crash logs suggests the app could not get the complete response. Shouldn't it go to the catch block in that case? (I am using a wrapper class to make a synchronous connection)
This will always be an issue in any app using the internet if the connection is poor. Is there any way we can avoid this?
Thanks.
I am using the code provided here as the base for creating connections and getting the response
This isn't a direct answer, but may I suggest the ASIHTTPRequest library? I searched around for a long time looking for a good networking library and this seemed to be pretty bullet-proof through all sorts of connection issues.
It took me an afternoon to remove the lousy library I wrote and to integrate it. The other nice thing about it is that it can be done asynchronously.
It is available here: http://allseeing-i.com/ASIHTTPRequest/