[CFNumber keep]：發送到已釋放實例的消息

Question

每次我在應用程序中觸發特定的segue時，都會收到EXC_BAD_ACCESS錯誤。 多虧了這兩個鏈接，我才知道啟用NSZombies后可以更輕松地排除EXC_BAD_ACCESS的麻煩。

如何在Xcode 4中設置NSZombieEnabled？

http://www.touch-code-magazine.com/how-to-debug-exc_bad_access/

我正在使用此應用程序進行即席測試。 http://www.raywenderlich.com/13511/how-to-create-an-app-like-instagram-with-a-web-service-backend-part-12

應用加載后，將顯示帶有圖片的UIScrollView。 當您點擊圖片時，將向該圖片的全屏拍攝觸發推送。 該應用程序可在iPad上完美運行，但在我的iPhone 4上，每次在推送按鈕前都會崩潰。 我已經堅持了一個星期。 我剛剛發現了什么是NSZombies以及如何啟用它們：啟用它們后，dubber的內容如下：

2015-07-03 22:26:36.170 iReporter[1878:60b] *** -[CFNumber retain]: message sent to deallocated instance 0x172e6210

在學習了如何在調試器中輸入“ bt”以獲取更多信息之后，這就是調試器現在要讀取的內容。

* thread #1: tid = 0x7246e, 0x2f1e515c CoreFoundation`___forwarding___ + 540, queue = 'com.apple.main-thread', stop reason = EXC_BREAKPOINT (code=EXC_ARM_BREAKPOINT, subcode=0xdefe)
* frame #0: 0x2f1e515c CoreFoundation`___forwarding___ + 540
frame #1: 0x2f134768 CoreFoundation`_CF_forwarding_prep_0 + 24
frame #2: 0x2f11e5a8 CoreFoundation`+[__NSDictionaryM __new:::::] + 536
frame #3: 0x2f1212f0 CoreFoundation`-[__NSPlaceholderDictionary initWithObjects:forKeys:count:] + 240
frame #4: 0x2f125dcc CoreFoundation`+[NSDictionary dictionaryWithObjectsAndKeys:] + 372
frame #5: 0x000c96a4 iReporter`-[StreamPhotoScreen viewDidLoad](self=0x172e7560, _cmd=0x32053af3) + 256 at StreamPhotoScreen.m:20
frame #6: 0x31a044aa UIKit`-[UIViewController loadViewIfRequired] + 518
frame #7: 0x31a04268 UIKit`-[UIViewController view] + 24
frame #8: 0x31b9036a UIKit`-[UINavigationController _startCustomTransition:] + 634
frame #9: 0x31aadd62 UIKit`-[UINavigationController _startDeferredTransitionIfNeeded:] + 418
frame #10: 0x31aadb6c UIKit`-[UINavigationController __viewWillLayoutSubviews] + 44
frame #11: 0x31aadb04 UIKit`-[UILayoutContainerView layoutSubviews] + 184
frame #12: 0x319ffd58 UIKit`-[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 380
frame #13: 0x3167d62a QuartzCore`-[CALayer layoutSublayers] + 142
frame #14: 0x31678e3a QuartzCore`CA::Layer::layout_if_needed(CA::Transaction*) + 350
frame #15: 0x31678ccc QuartzCore`CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 16
frame #16: 0x316786de QuartzCore`CA::Context::commit_transaction(CA::Transaction*) + 230
frame #17: 0x316784ee QuartzCore`CA::Transaction::commit() + 314
frame #18: 0x31a033e0 UIKit`_UIApplicationHandleEventQueue + 8232
frame #19: 0x2f1ae20a CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 14
frame #20: 0x2f1ad6da CoreFoundation`__CFRunLoopDoSources0 + 206
frame #21: 0x2f1abece CoreFoundation`__CFRunLoopRun + 622
frame #22: 0x2f116ebe CoreFoundation`CFRunLoopRunSpecific + 522
frame #23: 0x2f116ca2 CoreFoundation`CFRunLoopRunInMode + 106
frame #24: 0x3401c662 GraphicsServices`GSEventRunModal + 138
frame #25: 0x31a6314c UIKit`UIApplicationMain + 1136
frame #26: 0x000c699c iReporter`main(argc=1, argv=0x27d44cec) + 108 at main.m:16
(lldb) 

如果我需要發布更多代碼/信息，可能是這樣的：（編輯器有時會在崩潰時突出顯示的代碼部分以及告訴我它的EXC_BAD_ACCESS_）

[api commandWithParams:[NSMutableDictionary dictionaryWithObjectsAndKeys:@"stream", @"command", IdPhoto,@"IdPhoto", nil] onCompletion:^(NSDictionary *json) {

我要做的就是使用json調用上述數據，並通過push segue加載它。 它在iPad上絕對可以正常工作，但每次在iPhone 4上崩潰？

Answer 1

找到NSNumber屬性聲明，然后檢查是否錯誤地assign類型。