How to implement Daemon process for background task in iphone sdk 3.0? [closed]

Like qik.com or ustream.com , when they upload content from iphone to server , it works via daemon . So even when out of the app with exit , the task is still on with background daemon . Is there any method that I can implement daemon process in a same way ? Thanks !!!

Solution 1:

iPhone OS doesn't allow you to add background processes.

Solution 2:

What's more likely is, On Exit, they save state, then on Launch resume they transfer.

Solution 3:

Block thread at applicationWillTerminate: won't get killed in a short time, but WILL be rejected by App Store. For non-AppStore or personal applications, here is code:

@interface MyApplication : UIApplication
{
    BOOL _isApplicationSupposedToTerminate;
}
@property (assign) BOOL isApplicationSupposedToTerminate;
- (void)_terminateWithStatus:(int)status;
@end


@implementation MyApplication
@synthesize isApplicationSupposedToTerminate = _isApplicationSupposedToTerminate;
- (void)_terminateWithStatus:(int)status
{
    if (self.isApplicationSupposedToTerminate) {
        [super _terminateWithStatus:status];
    }
    else {
        return;
    }
}
@end

In main.m

    int retVal = UIApplicationMain(argc, argv, @"MyApplication", nil);

Delegate:

- (void)applicationWillTerminate:(UIApplication *)application
{
    [(MyApplication*)application setIsApplicationSupposedToTerminate:!kIsTransferDone];
}

This will stop application from terminating unless your transfer is done. Setup a timer for check timeout is important. And in applicationDidReceiveMemoryWarning:, quit your app by:

- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application { [(MyApplication*)application setIsApplicationSupposedToTerminate:YES]; [application terminateWithSuccess]; }

This should be able to make you finish your job. For jailbroken only.