如何使用目标c停止和启动app委托计时器？

Question

I have in my app login and logout process here I am facing so many problem with background timer services process. Below code I am maintaining for notification and JSON service background while applicationDidBecomeActive.

-(void)applicationDidBecomeActive:(UIApplication *)application
{
    checkJSONtimer = [NSTimer scheduledTimerWithTimeInterval:300 target:self selector:@selector(updateJSON) userInfo:nil repeats:TRUE];
    NSLog(@"%s", __PRETTY_FUNCTION__);
    application.applicationIconBadgeNumber = 0;
}

Problems below

1. Before login, timer activity started
2. After logout, timer activity not stopping
3. If I commented above timer after background to come active state, then timer not working
4. Every time without logout , cleared background app running again open I can go from login

FYI : Above timer selector method I am maintaining below three places

1. application didFinishLaunchingWithOptions
2. applicationDidBecomeActive
3. applicationDidEnterBackground

How to solve above problems. Please help me!

Answer 1

1. Before login, timer activity started

For that you have to make a check whether the user is log-in the app or not.For example

 -(void)applicationDidBecomeActive:(UIApplication *)application{ if(isUserLogedIn) { checkJSONtimer = [NSTimer scheduledTimerWithTimeInterval:300 target:self selector:@selector(updateJSON) userInfo:nil repeats:TRUE]; NSLog(@"%s", __PRETTY_FUNCTION__); application.applicationIconBadgeNumber = 0; } } 

2. After logout, timer activity not stopping

   For that, make a Notification which will trigger when the user log-out from the app.When the notification triggers the invalidate the timer.[myTimer inValidate].

3. If I commented above timer after background to come active state, then timer not working

   No need to comment the timer.Just manage the timer affectively.

4. Every time without logout , cleared background app running again open I can go from login.

   For that you have to manage the User session in NSUserDefaults.Check the value, if the value is not null, the log-in user automatically.

Answer 2

If you want to cancel the timer you can use something like this:

AppDelegate* appDelegate = (AppDelegate *)[UIApplication sharedApplication].delegate;

[appDelegate.checkJSONtimer invalidate]