iPhone - Get user interaction event and automatic logout

In my iPhone app I want to logout the user if nothing happens till about 2 minutes (e.g. the user puts down the phone). Does anybody has such issue? What is the best way to implement this feature? I 开发者_如何学Cthink I save the date of last event to NSUserDefaults, then on the next event first I check the current date. If the difference is larger than 2 minutes go to login screen, else refresh the stored date. But how can I get the touch event generally?

Thanks, madik

There's a method in UIApplicationDelegate for that:

- (void)applicationWillResignActive:(UIApplication *)application
{
/*
 Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
 Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
 */
}

EDIT: I didn't understand what you mean the first time. Check this accepted answer, it accomplish what you need. Basically you have to subclass UIApplication and override sendEvent method.

'NSTimer'

When you say "how can I get the touch event generally?", if you mean how can you tell if the user is idle or not, you'll have to set up some system to gather all touch events at a higher level in your app. You could update the last touch time you mentioned in NSUserDefaults but that may be inefficient during the run of the app, so you could just post the touch event to your main app delegate and have it save the time of last touch. Which would also be where you could set up the 2 minute timer.

Something like:

- (void) someAppDelegateMethodThatYouCallForAnyUserEvent
{
    [self.idleTimer invalidate];
    self.lastEvent = [NSDate now];
    self.idleTimer = [NSTimer scheduledTimerWithTimeInterval:120 target:self selector:@selector(logoutAndGotoLogin) userInfo:nil repeats:NO];
...
}

You'll also have to do some cleanup in your app delegate methods when the app goes to background etc if you support that behavior.