uidevicebatterystatedidchangenotification not working sometimes - ios

I am trying to check if device's charging port is working fine.
There are two scenarios -
a. when the charging cable is already plugged in.
b. when the charging cable is plugged in after sometime.
For case a, on viewDidLoad() I checked for enable batteryStateMonitoring and checked the current state of the battery. - It always works.
For case b, I tried using NSNotifications UIDeviceBatteryStateDidChangeNotification
override func viewDidLoad() {
UIDevice.current.isBatteryMonitoringEnabled = true
self.checkForCharging()
}
func checkForCharging() {
if UIDevice.current.batteryState == .full || UIDevice.current.batteryState == .charging {
self.updateUIForChargingTest()
} else {
NotificationCenter.default.addObserver(self,selector: #selector(ViewController.monitorBatteryStatus), name: NSNotification.Name.UIDeviceBatteryStateDidChange, object: nil)
}
}
func monitorBatteryStatus() {
if self.MonitorBatteryStatus(state: UIDevice.current.batteryState) == true {
self.updateUIForChargingTest()
}
else {
print("Device Battery State Unknown")
}
}
func MonitorBatteryStatus(state : UIDeviceBatteryState) -> Bool {
switch state {
case UIDeviceBatteryState.charging:
return true
case UIDeviceBatteryState.full:
return true
default:
return false
}
}
The NSNotification UIDeviceBatteryStateDidChangeNotification is not triggered everytime. It doesn't call the selector method everytime. Out of 10 times I plug-in the cable, it successfully responds only 2 times. Even when device begins charging.
Some people have marked it as duplicate. So for you kind information, this isnt an exact duplicate question because here I have applied certain approach to a problem which isnot working for me..AT ALL!! Solutions provided in the questions similar to my question are nt working for me, Since i have already tried them.

You should listen on Object device
NotificationCenter.default.addObserver(self,selector: #selector(ViewController.monitorBatteryStatus), name: NSNotification.Name.UIDeviceBatteryStateDidChange, object: UIDevice.current)

Related

How to detect if iOS devices is connected using wifi in Swift?

In an old, Objective-C based project I have been using the below code to detect if the iOS devices is currently connected using Wifi (not cellular).
My attempts to translate this code into Swift 5 failed due to the Objective-C pointers. Is there a clean way to use this solution in Swift?
Or are are there better ways to solve this nowerdays? I found solutions using the Reachability port to Swift or NWPathMonitor(). While they seem to work in general, these solution are used to monitor the connection state and send notifications on changes while one time checks are not (well) supported.
Event though these solution could be used to get the current connection state, this is done using delegate callback methods or closures. Thus it is not possible to use these solutions in existing code which was created to work "synchronously" (without callbacks/closures).
Is there a simply way to use localWiFiAvailable in Swift?
The code:
+ (BOOL)localWiFiAvailable {
struct ifaddrs *addresses;
struct ifaddrs *cursor;
BOOL wiFiAvailable = NO;
if (getifaddrs(&addresses) != 0) return NO;
cursor = addresses;
while (cursor != NULL) {
if ((cursor -> ifa_addr -> sa_family == AF_INET) && !(cursor -> ifa_flags & IFF_LOOPBACK)) { // Ignore the loopback address
// Check for WiFi adapter
#if TARGET_IPHONE_SIMULATOR
wiFiAvailable = true;
break;
#else
if (strcmp(cursor -> ifa_name, "en0") == 0) {
wiFiAvailable = YES;
break;
}
#endif
}
cursor = cursor -> ifa_next;
}
freeifaddrs(addresses);
return wiFiAvailable;
}
Details on why NWPathMonitor() cannot be used:
As #baronfac pointed out in his comment NWPathMonitor() can also deliver the current state, but this can only be done using its .pathUpdateHandler closure.
I am using a third-party library where I can override a souldSendData() -> Bool method. Sending the data should not be allowed on mobile connection but only on WiFi. The methodes requires an instant decision to return true or false. Waiting for the closure is thus not possible.
So, I am limited by the existing class here. Yes, connection could change any second, however this is a different problem. e.g. NWPathMonitor can be used to cancel the transfer when connection changes to mobile.
Solving this problem in Objectiv-C was no problem using the code shown above. The question is simply, if such a "direct" solution is possible in Swift as well. While using the Objectiv-C code in the Swift project would be possible I would prefer to keep the project Swift only.
As mentioned by Paulw11, the recommended approach is using NWPathMonitor. A common practice is the following within a UIViewController - class:
private var monitor: NWPathMonitor?
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
monitor = NWPathMonitor()
monitor?.pathUpdateHandler = { [weak self] path in
if !path.isExpensive { // this means the device is connected via WiFi
// enter your code here
}
}
let queue = DispatchQueue(label: "Monitor")
monitor?.start(queue: queue) // start to monitor the connection
}
override func viewWillDisappear(_ animated: Bool) {
monitor?.cancel() // end to monitor the connection
super.viewWillDisappear(animated)
}
EDIT:
Thanks to FLichter and Rob Napier for the clarification. Maybe it helps to use this approach:
func shouldSendData() -> Bool {
let monitor = NWPathMonitor()
return !monitor.currentPath.isExpense
}

Layout updates slowly after application becomes active

My goal is to check the authorization status of UNUserNotificationCenter (when the app becomes active again / enters the foreground) and turn a UISwitch either on or off, based on the info.
The function works and gets triggered right away but the UISwitch takes 3-5 seconds to update. Is there a better way to update it?
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(checkNotificationSettings), name: NSNotification.Name.UIApplicationDidBecomeActive, object: nil)
}
func checkNotificationSettings() {
self.center.getNotificationSettings { (settings) in
switch settings.authorizationStatus {
case .authorized:
self.notificationSwitch.isOn = true
case .notDetermined, .denied:
self.notificationSwitch.isOn = false
}
}
}
getNotificationSettings basically requests notification settings asynchronously so it takes some time until the completion block has been executed.
Apple documentation for the above method also says that the completion block may be executed on a background thread. However, everything that interacts with the UI must be run on the main thread otherwise you'll run into problems similar to what you've encountered in your case.
You should wrap it up with DispatchQueue.main to relay UI-related work to main queue and everything should work as expected:
self.center.getNotificationSettings { settings in
DispatchQueue.main.async {
self.notificationSwitch.isOn = (settings.authorizationStatus == .authorized)
}
}

proximityMonitoring may not be working as intended

for my iOS app i want to implement a feature where the screen should turns off (like when you answer a phone call) when the device is faced down.
so I've started by detecting the device orientation:
//in my ViewDidLoad
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(self.rotated(_:)), name: UIDeviceOrientationDidChangeNotification, object: nil)
//called when the device changes orientation
func rotated(notification: NSNotification){
if UIDevice.currentDevice().orientation == UIDeviceOrientation.FaceDown{
print("device = faced down")
}else{
print("device != faced down")
}
}
when device is down i've called
UIDevice.currentDevice().proximityMonitoringEnabled = true
else
UIDevice.currentDevice().proximityMonitoringEnabled = false
the problem is UIDeviceOrientationDidChangeNotification seems to act a little bit late so when the rotated() function is called, the device is already faced down and it turns out that in order for proximityMonitoringEnabled = true to turn off the screen the proximity sensor should not be already covered !
I'm pretty sure that this is an Apple limitation but maybe someone out there did found a solution or came across a workaround!
thanks in advance.
Approach:
Since iOS doesn't provide before changing Orientation we couldn't rely on 'UIDeviceOrientationDidChangeNotification'. Instead we can use CoreMotion Framework and access hardware's gyroscope for detecting possible FaceDown orientations and set proximityMonitoringEnabled appropriately.
Gyroscope Data:
Using Gyroscope observations below values can possibly detect FaceDown Orientation.
let gyroData = (minX:-3.78, minY:-3.38, minZ:-5.33, maxX:3.29, maxY:4.94, maxZ:3.36)
Solution in Swift:
class ProximityViewController: UIViewController {
let cmManager = CMMotionManager(), gyroData = (minX:-3.78, minY:-3.38, minZ:-5.33, maxX:3.29, maxY:4.94, maxZ:3.36)
override func viewDidLoad() {
super.viewDidLoad()
//Using GyroMotion
experimentCoreMotion()
}
//MARK: - Using Core Motion
func experimentCoreMotion() {
if cmManager.gyroAvailable {
//Enable device orientation notification
UIDevice.currentDevice().beginGeneratingDeviceOrientationNotifications()
cmManager.gyroUpdateInterval = 0.1
handleFaceDownOrientation()
}
}
func handleFaceDownOrientation() {
cmManager.startGyroUpdatesToQueue(NSOperationQueue.currentQueue()!, withHandler: { (data:CMGyroData?, error: NSError?) in
if self.isGyroDataInRange(data!) {
UIDevice.currentDevice().proximityMonitoringEnabled = (UIDevice.currentDevice().orientation == .FaceDown)
if UIDevice.currentDevice().orientation == .FaceDown { print("FaceDown detected") }
else { print("Orientation is not facedown") }
}
})
}
func isGyroDataInRange(val: CMGyroData) -> Bool {
return ((val.rotationRate.x > gyroData.minX && val.rotationRate.x < gyroData.maxX) &&
(val.rotationRate.y > gyroData.minY && val.rotationRate.y < gyroData.maxY) &&
(val.rotationRate.z > gyroData.minZ && val.rotationRate.z < gyroData.maxZ))
}
}
Hope my solution solves your query. Let me know the solution is working fine for your requirement.
Gyroscope & Accelerometer Observations:
I've experimented the possible values of FaceDown orientation using Gyroscope & Accelerometer. IMO, Gyroscope data seems fine but it's open to explore other hardware's sensors to detect FaceDown Orientation.

How to check when ios device just lost connection to internet

how to detect losing connection to network as fast as it can be
now im using reachabitity framework for swift and it takes abouut 3 sec to detect that there is no network so user can make the app crash
here how i check it :
func setupReachability() {
do {
self.reachability = try Reachability.reachabilityForInternetConnection()
} catch {
print("Cannot setup reachability monitoring")
return
}
self.reachability!.whenReachable = { reachability in
self.loginButton(true)
}
self.reachability!.whenUnreachable = { reachability in
self.loginButton(false)
}
do { try self.reachability!.startNotifier() } catch {
print("Cannot start reachability monitoring")
return
}
print("Started reachability")
}
You always, ALWAYS, must handle errors in your connections. You absolutely cannot rely on Reachability. You also cannot rely that your connection goes to the server that you want to connect to. It is possible and practically happens a lot that you get a reply from a totally different server in a totally different format than you expected, and you need to handle that. (Take your app to the nearest Starbucks and check whether it survives).

startBrowsingForNearbyPlayersWithHandler() in iOS 8 in Swift

I'm currently making a 2-player strategy board game in Swift and need to connect two iPads over local WiFi or Bluetooth. No matter what I've tried today, I can't get them to detect each other (I've tried over local WiFi and Bluetooth).
Here is my authorization code which runs in the UIViewController when my app first launches (which always returns "Self local player is authenticated." along with the ID:
private func authenticateLocalPlayer() {
var localPlayer = getLocalPlayer()
// If Apple were doing their job right, this is what the proper code should look like:
// var localPlayer = GKLocalPlayer.localPlayer()
if ( !localPlayer.authenticated ) {
localPlayer.authenticateHandler = { (viewController : UIViewController!, error : NSError!) -> Void in
NSLog("Error: \(error)")
if viewController != nil {
// Authenticated?
self.presentViewController(viewController, animated: true, completion: nil)
NSLog("viewController is not nil")
} else if (localPlayer.authenticated == true) {
NSLog("Self local player is authenticated.")
NSLog("My name is \(localPlayer.playerID)")
} else {
NSLog("Not authenticated")
NSLog("Player is \(localPlayer.playerID)")
}
}
} else {
NSLog("Player is already authenticated!")
}
}
and here is my code to detect nearby devices in a separate UIViewController:
override func viewDidLoad() {
devicesLabel.text = "Waiting for devices..."
searchForDevices()
NSLog("Ran searchForDevices()")
}
private func searchForDevices() {
GKMatchmaker.sharedMatchmaker().startBrowsingForNearbyPlayersWithHandler() {
var status = $1 ? "true" : "false"
self.devicesLabel.text = "Reachability changed for player \($0) with status: \(status)"
}
}
No matter what I do with my two iPads (both are model iPad 3), neither one ever sees the other. Am I calling startBrowsingForNearbyPlayersWithHandler correctly?
Also notice that in the authorization code above, I'm using the Objective-C workaround recommended by this post: Game Center not authenticating using Swift, since the "Swift way" of doing that didn't work for me either.
I also ran Spelltower across both devices over local WiFi, so it looks like the hardware is functioning properly. Any idea what could be going wrong here?
I decided to abandon developing this through Game Center and to use Multipeer Connectivity instead.
You are not registering a class to receive invitation updates. You need to register a class and implement methods conforming to the protocol for GKLocalPlayerListener. See my response in this post (it is in Objective-C, but the same concept applies):
Some startBrowsingForNearbyPlayersWithReachableHandler questions

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