[UIApplication sharedApplication].applicationState
will return current state of applications such as:
- UIApplicationStateActive
- UIApplicationStateInactive
- UIApplicationStateBackground
or if you want to access via notification see UIApplicationDidBecomeActiveNotification
Swift 3+
let state = UIApplication.shared.applicationState
if state == .background || state == .inactive {
// background
} else if state == .active {
// foreground
}
switch UIApplication.shared.applicationState {
case .background, .inactive:
// background
case .active:
// foreground
default:
break
}
Objective C
UIApplicationState state = [[UIApplication sharedApplication] applicationState];
if (state == UIApplicationStateBackground || state == UIApplicationStateInactive) {
// background
} else if (state == UIApplicationStateActive) {
// foreground
}
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