App hangs on restart with latest Flurry SDK and ios4

Question

I have a frustrating problem with the latest version of Flurry (Flurry iPhone SDK v2.5). When I start my app, quickly exit, then restart the App, the app briefly loads, flickers a black screen, then stays on the black screen. The black screen stays there until I press the home button, at which point I can restart the app normally. I looked into this further, and it turns out that app state delegates are getting called in the wrong order:

1. applicationDidBecomeActive //app finishes loading the first time
2. applicationWillResignActive //app begins to resign
3. applicationWillEnterForeground //At this point, I have quickly restarted the app, and this is called
4. applicationDidEnterBackground //When this delegate is called, the screen goes black
5. applicationDidEnterBackground //This gets called when I hit the home button again, after the screen has been hanging for a while.

So what I think this means is some processes take a bit longer to wrap up once I hit the home button, and if I try to start the app again too quickly there is some very odd behavior. If I wait a few seconds to restart the app, the app behaves normally.

To demonstrate this problem, I created the simplest app I could think of, which I will post here. I built this with XCode 3.2.3, in the 4.0 build directly onto my iphone device (iphone 4). This is important, because I couldn't reproduce this problem on the simulator. You can reproduce this app by creating a new navigation based project named simpleApp, and dropping this code in, with your own Flurry API key of course. Here is simpleAppAppDelegate.m:

#import "simpleAppAppDelegate.h"
#import "RootViewController.h"
#import "FlurryAPI.h"


@implementation simpleAppAppDelegate

@synthesize window;
@synthesize navigationController;


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    [FlurryAPI startSession:@"<your api key here>"];    

    [window addSubview:navigationController.view];
    [window makeKeyAndVisible];

    return YES;
}


- (void)applicationWillResignActive:(UIApplication *)application {
    printf("applicationWillResignActive\n");
}


- (void)applicationDidEnterBackground:(UIApplication *)application {
    printf("applicationDidEnterBackground\n");
}


- (void)applicationWillEnterForeground:(UIApplication *)application {
    printf("applicationWillEnterForeground\n");
}


- (void)applicationDidBecomeActive:(UIApplication *)application {
    printf("applicationDidBecomeActive\n");
}


- (void)applicationWillTerminate:(UIApplication *)application {
    printf("applicationWillTerminate\n");
}

- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application {
}

- (void)dealloc {
    [navigationController release];
    [window release];
    [super dealloc];
}

@end

And here is simpleAppAppDelegate.h:

#import <UIKit/UIKit.h>

@interface simpleAppAppDelegate : NSObject <UIApplicationDelegate> {

    UIWindow *window;
    UINavigationController *navigationController;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet UINavigationController *navigationController;

@end

So anyway, because so many apps are using Flurry I feel like I must be missing something very basic. What really boggles my mind is that I haven't found anyone at all complaining about this particular problem. Also, this is different from the problem in previous versions where the app would appear to start immediately, go black for a few seconds, then resume normally. That problem was solved by calling [FlurryAPI setSessionReportsOnCloseEnabled:false]; after I set the session, but that doesn't help in this case.

Anyway, has anyone else had this problem? I really hope it's just a stupid error on my part. I'm really excited to use Flurry but something like this would cause my app to get rejected.

Answer 1

I wrote Flurry about this and they got back to me really quickly that they'd look into this. About a week later they wrote back and said they fixed it in v2.6 which is now available. I can't seem to reproduce the problem anymore.

Not to say I'm awesome or anything, but I did kind of single handedly fix this bug.