I searched informations about possibilities when running an iOS app on background, but I didn't found same on different sites.
My application has to read the battery level (with step of 1%) and the time, but I don't know if I can read that when running on background.
Please if someone is sure about it or know a site to read these infos, it will be very nice.
EDIT : I've one more question, can I just open my app (to perform more actions) when the notification center return a battery state under 5% for example ?
No, you can't.
It's not possible to let your app running on background, it's iOS system's limitations.
In iOS 7.0 and later, you have opportunity to do some pre-fetch stuff even your app is not running, through the method like application:performFetchWithCompletionHandler:, but you should tell the device by posting remote notification from your server.
Related
I understand that this issue has already been covered extensively in the past, but I'd like to readdress it it appears that there is a lot of mixed messaging around the subject.
I have an application that should be periodically updated, roughly once a day at the minimum, to run some maintenance tasks. I have researched extensively on how to achieve this behaviour, but options such as background fetch and silent push notifications do not appear to work when the app has been terminated (swiped up on) by the user. (see this link for app states)
Will IOS wake up my app if it is in the terminated state, for example, if a user has swiped up on the app? I would like to find a solution that allows me to have the app run in the background in as many circumstances as possible.
What are my options here?
It is not possible to run a terminated app with Swift. Once an app has been terminated, it is no longer running and cannot be restarted. The only way to run the app again is to open it from the device's home screen or app launcher.
I'm developing a medical alert and record keeping app for iOS for a client. The app needs to be able to open itself at specific times based on a schedule that is set remotely.
I've searched around for how this can be done, and I keep running into other apps that let you schedule app launch times, but this needs to be a self contained solution.
I'd rather not JailBreak the iOS device to make it work, and I've come across articles that say iOS 9+ now has this capacity, but no instructions on how to make it come about.
Any clues, tutorials, or other information on how to accomplish this?
You can use "silent" push notifications (with "content-available") on iOS 7+ to launch the app when the push notification is received on the device. You will get a chance to process the notification, and the app will be launched if it's not already running.
However, it still won't work if the user has force killed the app.
Also, iOS will not launch your app if it feels you've gone over the daily processing time or data quota.
My app is an emergency app. It will be used by people in emergency and disasters.
It's possible that they got stuck in situations where they just don't have the time to enter or draw their password on the lock screen, launch the app and push a button. Is it possible that my app can ask the OS to launch the app if user throw their iPhone up in the air or shake it vigorously or something else.
What I wish to achieve by this ?
I want that OS launches my app in background if the user say shake his/her iPhone vigorously. Once launched my app will make a network request and keep running in background for short time.
PS:I think it's possible with the accelerometer.
Accelerometer will not work because Apple doesn't allow background processes opening apps. In your case, user must be opening the app by himself/herself manually. (PS. As far as I know, it's possible in Android)
iOS background tasking problems aside:
Apple don't allow apps that encourage the user to do things that might damage their iOS device. So your 'throw in the air' idea is out.
As for shaking the device -- this just isn't practical. What if the device gets shaken by accident? You've then got false alarms to deal with.
The crux of the issue is that something that triggers an emergency response should be a deliberate action which is hard to do trigger by accident.
This cannot work - and here's why.
Your app would need to run in background to handle motion events. Apps running in background can get killed at any time, i.e. if memory gets low. There might be some restrictions about running and and resource usage as well.
An app in the background cannot bring itself to the front.
Launching from a locked screen would bring great security risks.
Throwing into the air seems like a gesture that can easily be triggered by accident.
I must admit that I'm pretty happy that those apps are not allowed on the AppStore - as it would open many doors that I'd like to see kept close.
I'm newbie iOS. I have been develop Phonegap for Android and iOS. My App is update data from server every 1hour. In Android, i use service to do that. My app in Android working very good. Now, i want to develop version for iOS, and i have problem when update data from server every 1hour. I was research but not find anyway for my app.I don't know what's solution to replace for service in Android. Can you help me, what's solution. This have been kill me. Thank you so much.
Short answer is NO as Apple has restriction on background task running especially cases like yours.
But if you are downloading small amount of content, you do have some other options. From IOS 4.0 or above, you can declare your app to run in background when you fall under the following categories:
Audio
Location updates
Voice over IP
Newsstand downloads
External accessory communication
Bluetooth networking
Bluetooth data sharing
Background fetch (IOS 7)
Remote notifications (IOS 7)
In order to do so, you need to flag your app in the info.plist for Required Background Modes option. Apple will review your app specific in this area once you declared the option.
For your case to download the data, the possible option is to use the new feature in IOS 7 that's the background fetch or remote notification above. The suggestion from DOM was not asking you to download the content through push notification. But instead to use push notification to wake up your application and start downloading new content.
If you don't want to use push notification, the only way to go is register for background fetch. However, no matter which option you want to use, each download will only last for 30 seconds. And after that, your app will put into suspension mode again.
you can have a look on the link here:
Declaring Your App’s Supported Background Tasks
I think your best bet would be to use the push services instead of having your app go get data. Making your app do it is unreliable with phonegap apps because you cant create a service interface and you can not guarantee that your app will be running. With push service though, if your app isn't running, it will be woken up in a manner of speaking.
Take a look at this great how-to article that also discusses what push provides you.
This is a strange one, I have a need to create an iOS app that runs in the background on an iOS device, but can not be visible on the Home screen of the device. The app may need to show up in Settings to configure a few options, but it mostly needs to run behind the scenes.
I do not need to publish this app on the app store, it is strictly an enterprise app for my company.
Does anyone know how this kind of behavior might be achieved? Configuration profiles? API's? etc?
Edit: Jailbreaking the device is not really an option for us. We have to keep the devices as they are.
Backgrounding
There are several methods to get permanent background execution:
a) Silent audio which is mentioned by JRG-Developer
b) Usage of beginBackgroundTaskWithExpirationHandler + turning location manager on/off (it will reset remaining time to 600 seconds)
Making app invisible
You can use SBAppTags in Info.plist (take a look at this: How to remove app icon programatically from jail broken iPhone app?)
It will make your icon not visible on Home screen.
I've no idea how you can tackle the not be visible on the home screen criteria, but there are certain services that are allowed to be run in the background continuously, notably:
Background Audio (even silent audio)
While this is indeed very hacky, short of jailbreaking the devices, this may be your best bet.
While it's unlikely / very difficult to get past the review process, in the event for some reason you do need to (attempt) to publish this app to the App Store, some apps are even available on the App Store which take advantage of this hack, such as PasteBot.
You should definitely read their write-up here about getting their app's Cut-and-Paste functionality to work while in the background:
http://tapbots.com/blog/pastebot/pastebot-music-in-background
Another out-of-the-box idea, why not use Android devices instead, which do support multitasking?
Two methods:
Jailbreak. A jailbroken iPhone is essentially a Mac and you can use all Mac UNIX programming tricks - spawn a daemon (you can even ask launchd to do that), or something. You can set up enteprise-wise Cydia source. Refer to saurik's website for a walkthrough and set up an experimental server using Ubuntu (which used apt too)
A non-jailbreak way may be possible, but it will depend on what your app is doing. You can try use enterprise-wise push notifications.
Given that this is impossible to do on non jailbroken phones, I'd suggest the following:
develop a directory app, or a phone list app, something that is specific to your company.
have it connect to a web service once a day to register the device ID (so you know the user has not deleted the app)
tell users they need to keep the app open at all times (and if a user's device does not register one day, send them an email asking them to launch the app).
Now you can send back whatever you want with the app. If they kill it, you'll know the next day when you have a script look at the logs.
If you think this is a terrible idea, it is, but its the best you are going to get on iOS right now.
EDIT: you could send a notification every day - say in the AM - to make sure the user opened the app if it wasn't running.
From my experince, this kind of behaviour cannot be achieved on iOS. When an app enters into background, it is active only for a small particular amount of time. After that, it goes into hybernate state. It stops working. So the behaviour you said can not be achieved without abusing iOS workflow. Thats why some call iOS's multitasking as not true multitasking. Only jailbreaking might help your case. That was for one case. The second one where the app cannot be seen on home screen is again, impossible. It has to be on springboard to run.