IOS app to check battery level in background

Question

Can I check the battery level when our application is in the background?

I am currently working on one iOS application in which the user will be alerted when the battery reaches a certain level.

I searched google / over overflow. but find nothing useful. I can determine the battery level when the application is in the foreground. But we all know that the apple does not allow the application to run in the background.

So my question is: how can I get the current battery level event, even if my application is in the background.

Here is a similar application. This is a paid application. But, seeing the screenshot, you get the idea that I want to say.

https://itunes.apple.com/it/app/battery-alert!/id416283462?mt=8

Answer 1

UIDevice *device = [UIDevice currentDevice];
device.batteryMonitoringEnabled = YES;
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(batteryChanged:) name:@"UIDeviceBatteryLevelDidChangeNotification" object:device];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(batteryChanged:) name:@"UIDeviceBatteryStateDidChangeNotification" object:device];

// Your notification handler
- (void)batteryChanged:(NSNotification *)notification
{
    UIDevice *device = [UIDevice currentDevice];
    NSLog(@"state: %i | charge: %f", device.batteryState, device.batteryLevel);
}

check this code ...