multitasking

问题 Yes, I know if I wish my app to be responsive to users' multitasking actions, such as switch to another app, I should deal with - (void)applicationWillResignActive:(UIApplication *)application - (void)applicationDidBecomeActive:(UIApplication *)application What if my app is doing a quite-long time consuming operation (like downloading a big file) and the user causes my app to enter the background? Will that operation automatically be suspended and resumed when the user comes back to my app?

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问题 i wrote an application on the Xcode 4.2 using iOS SDK 5.0. i have set the UIApplicationexitonsuspend in the info.plist to YES but when i double press the home button, the application is still in the multitasking bar. i have deleted the app from my iPhone 4s and resend it again from Xcode but still the exit on suspend does not work. application still lingers on multitasking tab. 回答1: The fact that your app icon is shown in the "multitask tab" does not mean that your app is still there. The

问题 i wrote an application on the Xcode 4.2 using iOS SDK 5.0. i have set the UIApplicationexitonsuspend in the info.plist to YES but when i double press the home button, the application is still in the multitasking bar. i have deleted the app from my iPhone 4s and resend it again from Xcode but still the exit on suspend does not work. application still lingers on multitasking tab. 回答1: The fact that your app icon is shown in the "multitask tab" does not mean that your app is still there. The

问题 I am confused on the different terms as to their actual differences. What are each of them and what do they actually mean? My IT teacher at school gives us one definition the one day, and another the next, so please can you shed some light for me. Thanks. 回答1: A thread is a sequence of program instructions that are executed by the machine. We call a program multi-threaded when a single execution of the program has more than one thread. Multi-threading can be simulated on a single-processor

问题 Is applicationDidEnterBackground ALWAYS called before applicationWillTerminate in an iOS app? I know that applicationWillTerminate is not always called (multitasking) - but when it is called, is applicationDidEnterBackground ALWAYS called first? I don't want to duplicate code unnecessarily by including it in applicationWillTerminate if it is already included in applicationDidEnterBackground , for an app that supports multitasking. 回答1: in ios 4.0 and later applicationDidEnterBackground is

问题 Am I missing something here with Multitasking feature. I know we can execute a task in background, but what I really need is that task continues execution when app goes in background. So what I need is different than starting a new task in background. If images are being loaded in a view and user presses the home button to make the app go in background, I want that images continue to load and when user makes the app active again, he can see all the loaded images. How can this be done? Thanks

问题 The problem is this - My app lets you passcode protect itself. I use an interface just like passcode protecting the phone. This has always worked fine, until multi-tasking came along. The passcode protection still works, but there is one issue. Apple does something special to make it look like our apps are loading quicker when they come back from the background. The os takes a picture of our screen just before the user leaves the app, and it displays that while the rest of the app is still

问题 The problem is this - My app lets you passcode protect itself. I use an interface just like passcode protecting the phone. This has always worked fine, until multi-tasking came along. The passcode protection still works, but there is one issue. Apple does something special to make it look like our apps are loading quicker when they come back from the background. The os takes a picture of our screen just before the user leaves the app, and it displays that while the rest of the app is still

问题 I was wondering whether Lua has any preemptive multitasking facilities built-in. I would like to have concurrent threads to use on my multi-core system. I looked into coroutines (see lua-users.org/wiki/CoroutinesTutorial and stackoverflow.com/questions/3107165/there-is-a-type-named-thread-in-lua-does-anyone-know-something-of-this), but it seems not to fit the bill. I wrote the following code: function foo(ver) local iter = 1; while true do print("foo ver="..ver.." iter="..iter); iter = iter +