iPhone: applicationDidFinishLaunching & handleOpenUrl

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Problem:

You use the applicationDidFinishLaunching method to kick off your application. This event fires automatically on your delegate whenever your app launches.

If your app launches from a special url schema (tel://, http://, mailto://), then another event is fired:

handleOpenUrl

As you might have noticed in the LaunchMe sample project that ships with Xcode, these two methods will most likely conflict.

Solution:

Move the functionality from applicationDidFinishLaunching and put it in another method, like postLaunch. Then add a member variable to the application delegate to keep track of how the app started:

@interface YourAppDelegate : NSObject  {BOOL launchDefault;}

@property BOOL launchDefault;

Then put this in applicationDidFinishLaunching:

launchDefault = YES;[self performSelector:@selector(postFinishLaunch) withObject:nil afterDelay:0.0];

Then in handleOpenUrl, add this:

launchDefault = NO;

Lastly, write the postLaunch method and make it check the launchDefault variable.

- (void)postLaunch{ if (launchDefault){     // Add your functionality from applicationDidFinishLaunching here. }else{     // don't do anything....let handleOpenURL run }

}

How does this work?

You’re effectively adding a method to the event chain to be called after all other events. You’re putting a 0 second delay on it, so it shouldn’t add any extra time to the overall loading time.