我是iOS开发的新手,我用Swift写了一个RSS提要阅读器。源项显示在 UITableView 中。当我选择(触摸、单击)某个项目时,将显示一个新的 UIView,显示所选项目的源说明。
它可以在iOS8上运行,但是当我在iOS7上尝试时,应用程序崩溃,我得到以下输出:
2015-03-06 21:18:50.009 FeedReaderApp[9084:607] -[FeedReaderApp.TableViewController showViewController:sender:]: unrecognized selector sent to instance 0x7be8b100
2015-03-06 21:18:50.012 FeedReaderApp[9084:607] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[FeedReaderApp.TableViewController showViewController:sender:]: unrecognized selector sent to instance 0x7be8b100'
*** First throw call stack:
(
0 CoreFoundation 0x006a61e4 __exceptionPreprocess + 180
1 libobjc.A.dylib 0x01c4d8e5 objc_exception_throw + 44
2 CoreFoundation 0x00743243 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275
3 CoreFoundation 0x0069650b ___forwarding___ + 1019
4 CoreFoundation 0x006960ee _CF_forwarding_prep_0 + 14
5 FeedReaderApp 0x000b8068 _TFC12FeedReaderApp19TableViewController9tableViewfS0_FTCSo11UITableView23didSelectRowAtIndexPathCSo11NSIndexPath_T_ + 1400
6 FeedReaderApp 0x000b8139 _TToFC12FeedReaderApp19TableViewController9tableViewfS0_FTCSo11UITableView23didSelectRowAtIndexPathCSo11NSIndexPath_T_ + 89
7 UIKit 0x00e1d9a1 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1513
8 UIKit 0x00e1db14 -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 279
9 UIKit 0x00e2210e __38-[UITableView touchesEnded:withEvent:]_block_invoke + 43
10 UIKit 0x00d510aa ___afterCACommitHandler_block_invoke + 15
11 UIKit 0x00d51055 _applyBlockToCFArrayCopiedToStack + 403
12 UIKit 0x00d50e76 _afterCACommitHandler + 532
13 CoreFoundation 0x0066e36e __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 30
14 CoreFoundation 0x0066e2bf __CFRunLoopDoObservers + 399
15 CoreFoundation 0x0064c254 __CFRunLoopRun + 1076
16 CoreFoundation 0x0064b9d3 CFRunLoopRunSpecific + 467
17 CoreFoundation 0x0064b7eb CFRunLoopRunInMode + 123
18 GraphicsServices 0x043a15ee GSEventRunModal + 192
19 GraphicsServices 0x043a142b GSEventRun + 104
20 UIKit 0x00d33f9b UIApplicationMain + 1225
21 FeedReaderApp 0x000bc6ae top_level_code + 78
22 FeedReaderApp 0x000bc6eb main + 43
23 libdyld.dylib 0x026676d9 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
这是我的UITableViewController的代码,它处理表格单元格的选择:
class TableViewController: UITableViewController, MWFeedParserDelegate {
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
currentItem = self.items[indexPath.row] as MWFeedItem
let vc : AnyObject! = self.storyboard?.instantiateViewControllerWithIdentifier("detailView")
self.showViewController(vc as UIViewController, sender: vc)
}
}
感谢您的任何帮助!
iOS 7 没有 showViewController 方法,只存在于 iOS8 中
if (self.respondsToSelector(Selector("showViewController")))
{
self.showViewController(vc as UIViewController, sender: vc)
}
else if(self.navigationController.respondsToSelector(Selector("pushViewController")))
{
self.navigationController!.pushViewController(vs as UIViewController, animated: true)
}