一般在ARC在管理模式下,很难过度释放对象。以下是我将遇到的问题之一crash。
* thread #1: tid = 0x31d1db, 0x0000000102e5e00b libobjc.A.dylib`objc_msgSend 11, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18) frame #0: 0x0000000102e5e00b libobjc.A.dylib`objc_msgSend 11 frame #1: 0x0000000101968212 UIKit`-[UISectionRowData refreshWithSection:tableView:tableViewRowData:] 2353 frame #2: 0x000000010196de45 UIKit`-[UITableViewRowData rectForFooterInSection:heightCanBeGuessed:] 320 frame #3: 0x000000010196df3a UIKit`-[UITableViewRowData heightForTable] 56 frame #4: 0x00000001017c0af0 UIKit`-[UITableView _updateContentSize] 381 frame #5: 0x00000001017ddecd UIKit`-[UITableView didMoveToWindow] 65 frame #6: 0x00000001017649a0 UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] 1482 frame #7: 0x0000000101775333 UIKit`-[UIScrollView _didMoveFromWindow:toWindow:] 55 frame #8: 0x000000010176468e UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] 696 frame #9: 0x000000010176468e UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] 696 frame #10: 0x000000010176468e UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] 696 frame #11: 0x000000010176468e UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] 696 frame #12: 0x000000010175d112 UIKit`__45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke 125 frame #13: 0x000000010175d086 UIKit`-[UIView(Hierarchy) _postMovedFromSuperview:] 437 frame #14: 0x0000000101766f4b UIKit`-[UIView(Internal) _addSubview:positioned:relativeTo:] 1604 frame #15: 0x00000001017c816f UIKit`-[UITableView _addContentSubview:atBack:] 245 frame #16: 0x00000001017e08cd UIKit`__53-[UITableView _configureCellForDisplay:forIndexPath:]_block_invoke 2403 frame #17: 0x00000001017615ce UIKit` [UIView(Animation) performWithoutAnimation:] 65 frame #18: 0x00000001017dff5b UIKit`-[UITableView _configureCellForDisplay:forIndexPath:] 312 frame #19: 0x00000001017e74cc UIKit`-[UITableView _createPreparedCellForGlobalRow:withIndexPath:willDisplay:] 533 frame #20: 0x00000001017c6fb1 UIKit`-[UITableView _updateVisibleCellsNow:isRecursive:] 2846 frame #21: 0x00000001017dce3c UIKit`-[UITableView layoutSubviews] 213 frame #22: 0x0000000101769973 UIKit`-[UIView(CALayerDelegate) layoutSublayersOfLayer:] 521 frame #23: 0x00000001043efde8 QuartzCore`-[CALayer layoutSublayers] 150 frame #24: 0x00000001043e4a0e QuartzCore`CA::Layer::layout_if_needed(CA::Transaction*) 380 frame #25: 0x00000001043e487e QuartzCore`CA::Layer::layout_and_display_if_needed(CA::Transaction*) 24 frame #26: 0x000000010435263e QuartzCore`CA::Context::commit_transaction(CA::Transaction*) 242 frame #27: 0x000000010435374a QuartzCore`CA::Transaction::commit() 390 frame #28: 0x00000001016ee54d UIKit`-[UIApplication _reportMainSceneUpdateFinished:] 44 frame #29: 0x00000001016ef238 UIKit`-[UIApplication _runWithMainScene:transitionContext:completion:] 2642 frame #30: 0x00000001016edbf2 UIKit`-[UIApplication workspaceDidEndTransaction:] 179 frame #31: 0x000000010480c2a3 FrontBoardServices`__31-[FBSSerialQueue performAsync:]_block_invoke 16 frame #32: 0x00000001034f253c CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ 12 frame #33: 0x00000001034e8285 CoreFoundation`__CFRunLoopDoBlocks 341 frame #34: 0x00000001034e8045 CoreFoundation`__CFRunLoopRun 2389 frame #35: 0x00000001034e7486 CoreFoundation`CFRunLoopRunSpecific 470 frame #36: 0x00000001016ed669 UIKit`-[UIApplication _run] 413 frame #37: 0x00000001016f0420 UIKit`UIApplicationMain 1282 * frame #38: 0x0000000101513903 NiuHelper`main(argc=1, argv=0x00007fff5e7ac350) 115 at main.m:14 frame #39: 0x000000010844d145 libdyld.dylib`start 1
看问题还以为是苹果的bug,搜索后,我看到一个人遇到了同样的问题。一位网友的回复是:
Sorry I never came back to this thread. So the issue is that this nib is being loaded by a view controller through its initWithNibName:bundle: method. That method will not retain any top level objects on its own. So your Highscore Controller object is loaded from the nib and then autoreleased, which means it goes away pretty quickly after that. So you need to retain that object. One easy way to do that is to define a property in your view controller subclass for this object (specifying 'retain' and 'IBOutlet' of course) and then connect that outlet to this Highscore Controller in IB.
想到自己在这里创造了一个联想VC,将VC的view如果添加到界面中,则不管这个VC了,VC被释放似乎要注意这一点autorelease的问题了,即使是在同一个线程中还是可能存在问题。/p>
- (TopTabPage *)TopTabControl:(TopTabControl *)tabCtrl
pageAtIndex:(NSUInteger)index
{
TopTabPage *page = [[TopTabPage alloc] initWithFrame:CGRectMake(0,
0,
CGRectGetWidth(self.view.frame),
CGRectGetHeight(tabCtrl.bounds) - 30
)];
NHNewsModel *NewsModel = [self.tagListModel.result.channelList objectAtIndex:index];
NHNewsContentViewController *contentViewVC = [[NHNewsContentViewController alloc] initWithChannelID:NewsModel.getChannelID
andContentRect:page.bounds];
[page addSubview:contentViewVC.view];
// [_array addObject:contentViewVC];
return page;
}
将VC retain之后就没有问题了。苹果的arc也不能完全相信啊。