unity iOS应用切换到后台之后持续运行

https://forum.unity3d.com/threads/continue-running-app-in-background-for-audio-generation-ios.110512/

class IHookEvent;

bool PlayerLoop (bool, bool,
IHookEvent*);

NSTimer *aTimer;

@implementation AppController

- (void) applicationDidBecomeActive:(UIApplication*)application

{

    if (_didResignActive)

    {

[aTimer
invalidate];

    }

    _didResignActive = NO;

}

- (void) applicationWillResignActive:(UIApplication*)application

{

    aTimer = [NSTimer
scheduledTimerWithTimeInterval:1.0 target:self
selector:@selector(UpdateUnityInTheBackground) userInfo:nil
repeats:YES];

    _didResignActive = YES;

}

- (void) UpdateUnityInTheBackground

{

    PlayerLoop(true, true, NULL);

}