I am developing a network application on iPhone that requires internet connection all the time. However, once I login to the server and keep the iPhone idle for a while, the iPhone goes to sleep mode and disconnects my network connection (it logs me out).
If I run the same application on iPhone, while the iPhone is connected to the PC through USB cable, it never loses its network connection.
In the info.plist file I have added these two flags, but does not seem to have any effect.
UIRequiresPersistentWifi -> true
SBUsesNetwork - integer ->3
Am I missing anything? Could you please let me know how can I make sure that the network connection is persistent throughout the life of the application?
In your application delegate ("appDelegate"), disable the idle timer in the +initialize method:
myApp.idleTimerDisabled = YES;
Note that this will keep your iPhone from sleeping while your app is open. This can present issues with battery life.
Another option might be to set up a background thread that opens a small CFStream on a timed basis.
What do you mean by "logs me out" here? At the network level, there is no "logged in" (*). There are only packets. You send them or you don't. So does your server process have some expectation of packets or messages arriving periodically? If it does, then you must send them, and that means that you can't go idle (idleTimerDisabled = YES). If you control the server, it is better to make it less demanding about how often you talk to it. This all happens well above the network layer, however.
UIRequiresPersistentWifi means that the Wifi radio is kept on while you're app is running, even if you don't talk on it. This is important for receiving data. Otherwise you drop off the network and others can't talk to you after about 30 minutes. It should be set in Info.plist, but this is certainly in your app bundle. If it weren't, your app wouldn't launch, so that isn't the problem.
(*) The cell network does have the concept of logged in, but that's not what's causing your problem.
Related
My iPhone app sends data persistently over the network, and can handle having the network completely unavailable for a time. However I do my dev on an ipod and have difficulty testing 3G connectivity issues; My question: is there period of non-connectivity, while an app is in the foreground, after which the iphone will stop checking for the network, such that there are no bars and reachability returns 0 until the user "wakes" the phone, e.g. by locking/unlocking? Or can e.g. 1 hr without data network pass and the iphone will recognize that the network is back and reachability will start returning true (I am polling every 1 minute while there is not connection to my server).
This is my experience with wifi: if, while running my app, the ipod hasn't connected to a wifi network for 1/2 hr, it stops looking for networks, and I need to lock and unlock it to stir the device into looking again.
One other thing: the iPhone has the screen dimmed by the proximity sensor while all this persistent network use is happening.
Wi-Fi going down after 30 min of inactivity is a documented behavior. Cellular network is always active, unless turned off by the user. So if it goes down for a while it should get back online automatically when possible even if there was no user activity.
I want to log the number of bytes being transferred from my iPhone app to server so that I could put a watch on the bandwidth being eaten up and could take necessary actions.
How can I do this?
In Instruments there is Network Activity Monitor that does what you need. You can always correlate your findings with network usage numbers in your Settings.app on actual device. Settings->General->Usage
Update:
Second approach:
Make sure you use cellular connection first
Reset your data counter.
Launch your app and perform operations that interested in
Quit your app and see the traffic used in Settings.app
On the picture below is traffic used for my app in 2 minutes.
We are in the process of developing an method of caching so that our app can continue to operate in an area with very little/no signal.
Obviously users will try to continue to use functions that require data and we need to handle the inevitable failure of these requests appropriately.
Essentially we are sat in the office, switching airplane mode on and off to simulate entering/exiting signal then adjusting our app to fix any issues this may arise.
What I'd like to know is, is using airplane mode going to give us a reasonable simulation of entering/exiting an area with no data or are there other implications?
I've seen questions raising the issue that the 3G/EDGE connection may not always wake up after airplane mode is switched on - while I appreciate this method is no way as good as actually being out in the field testing, if we can get a reasonable simulation and account for the majority of the problems that arise then I think this is an acceptable tradeoff.
I apologise if this has been asked before, I did do a search on here & on google but couldn't find any appropriate results.
You should try the Network Link Conditioner
There is a WWDC 2012 session called Networking Best Practices that mentions it (but he does not explain how to use it there).
To get it, you have to go to XCode/Open Developer Tool/More Developer Tools.. and download the latest Hardware IO Tools for XCode.
Once you install it from the IO Tools pkg, "Network Link Conditioner" will appear in System Preferences
You can then do something like 100% packet loss to simulate one of those routers that pretends you are connected but actually doesn't work.
On iOS, the network link conditioner is under Settings / Developer (you must have enabled Developer mode in XCode first to see it)
The main problem is that in the Airplane Mode the networking operations fail fast, while spotty mobile signal will lead to timeouts and a-few-bytes-an-hour speeds. This is usually a significant difference from the UI viewpoint. (It might be worth a try to use some bandwidth throttle to starve the testing machine and see how it behaves when the network starts to break?)
A few years back, when testing remote devices which used the cell network to communicate with the 'home base', we did things like move them into a shielded room (make shift), place large shields on three of four sides to force them to connect to a certain tower (and therefore, network), etc. Brute force physical methods. Since this actually cuts off the signal, it may be a more realistic approach.
You may also want to try this through your wlan-router. First, disable data roaming on your iPhone. Then, let the iPhone be connected to the internet through your wlan network. Then, disconnect the gateway on your wlan router while your iPhone is still connected to the wlan network.
This depends on what failure modes you are trying to test.
I use Airplane mode as a first pass check to make sure an app submission isn't quickly rejected.
Other network failure handling checks might include:
3G only (no wifi).
WIFI only (in Airplane mode).
Pulling the power cord on the WIFI access point.
Pulling the network cable from the back of the WIFI access point after connecting to it (Reachability may falsely say yes).
Walking in and out of a basement
elevator (or other Faraday cage) in the middle of a transfer.
Driving between 2 cell towers during a data transfer.
Walking between 2 enabled WIFI access points between connection and data transfer.
Starting the app after more than 30 minutes of device inactivity (radios may be idle).
Running the app while another app (Safari, Mail) is downloading in the background.
etc.
I want to check the user whether using whether wifi/3G connect or not, how can I check this behavior? thank you.
Use Apple's "Reachability" sample app. It's become the code most used for determining network connectivity.
http://developer.apple.com/iphone/library/samplecode/Reachability/Introduction/Intro.html
You can check once at launch time for network access, or set yourself up as a notification consumer of network connection change messages.
This is important these days because Apple will test your app in Airplane Mode, and if it requires network connections it can't get, but doesn't handle that nicely, they'll bounce your submission.
Sometimes I am experiecing a delay while receiving APN , while at other times its working absolutely fine.
I am also connecting to the feedback server at ssl://feedback.sandbox.push.apple.com , but its not showing any data.
What are the possible reasons for the delay?
Thanks
Delay can happen if you've got a bad connection on 3G or Edge (iPhones use those, not wifi, for push unless they're totally unavailable). If the connection is dropped but the device doesn't know it, it'll wait until it does a heartbeat and realizes the connection is closed.
Also, if you're using an iPod Touch, the connection to the push servers will only be maintained while the backlight is on or you're plugged in via USB; otherwise the wifi connection will be dropped when the backlight goes off to save power, and it'll poll for new notifications every half an hour.