iphone UITable reloadRowsAtIndexPaths非常奇怪的问题

Question

所以我正在尝试使用传入图像更新单元格.我有一个协议,在完成图像DLing时回调相应的方法.UITable的源代码是"会议"对象的NSArray.每个会议都保存其表格单元格的indexPath,我得到了 -

(UITableViewCell *)tableView:(UITableView *)_tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    Meeting * meeting = [tableDataSource objectAtIndex:indexPath.row];
... cell's init code
    meeting.cellPath = indexPath; // also tried [indexPath copy];
...
}

问题是当我尝试使用存储的IndexPath更新单元格时我得到一个奇怪的错误,其中说明了一些我没有的NSMutable数组:

2012-07-20 20:15:18.007 MyNewbieApp[5734:207] meeting.cellPath =  [row = 2,section = 0]
2012-07-20 20:15:18.705 MyNewbieApp[5734:207] meeting.cellPath =  [row = 4,section = 0]
2012-07-20 20:15:18.728 MyNewbieApp[5734:207] meeting.cellPath =  [row = 5,section = 0]
2012-07-20 20:15:18.730 MyNewbieApp[5734:207] downloadDidFinishDownloading <NSIndexPath 0x79456f0> 2 indexes [0, 5]
2012-07-20 20:15:18.732 MyNewbieApp[5734:207] *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[NSMutableArray objectAtIndex:]: index 3 beyond bounds [0 .. 2]'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x02c70b99 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x02a6540e objc_exception_throw + 47
    2   CoreFoundation                      0x02c66695 -[__NSArrayM objectAtIndex:] + 261
    3   UIKit                               0x00556327 -[_UITableViewUpdateSupport(Private) _setupAnimationsForExistingVisibleCells] + 264
    4   UIKit                               0x00555b9b -[_UITableViewUpdateSupport initWithTableView:updateItems:oldRowData:newRowData:oldRowRange:newRowRange:context:] + 436
    5   UIKit                               0x003ab5d6 -[UITableView(_UITableViewPrivate) _updateWithItems:withOldRowData:oldRowRange:newRowRange:context:] + 1323
    6   UIKit                               0x003a7f03 -[UITableView(_UITableViewPrivate) _endCellAnimationsWithContext:] + 9179
    7   UIKit                               0x003974d3 -[UITableView reloadRowsAtIndexPaths:withRowAnimation:] + 56
    8   MyNewbieApp                         0x00017354 -[MeetingsVC downloadDidFinishDownloading:] + 174
    9   MyNewbieApp                         0x000173a6 -[MeetingsVC download:didFailWithError:] + 43
    10  MyNewbieApp                         0x00010e5f -[Meeting image] + 317
    11  MyNewbieApp                         0x00016f49 -[MeetingsVC tableView:cellForRowAtIndexPath:] + 2141
    12  UIKit                               0x0039ed6f -[UITableView(UITableViewInternal) _createPreparedCellForGlobalRow:withIndexPath:] + 619
    13  UIKit                               0x00394e02 -[UITableView(UITableViewInternal) _createPreparedCellForGlobalRow:] + 75
    14  UIKit                               0x003a9774 -[UITableView(_UITableViewPrivate) _updateVisibleCellsNow:] + 1561
    15  UIKit                               0x003a17ec -[UITableView layoutSubviews] + 242
    16  QuartzCore                          0x02619481 -[CALayer layoutSublayers] + 177
    17  QuartzCore                          0x026191b1 CALayerLayoutIfNeeded + 220
    18  QuartzCore                          0x026122e0 _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 302
    19  QuartzCore                          0x02612040 _ZN2CA11Transaction6commitEv + 292
    20  QuartzCore                          0x02642ebb _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 99
    21  CoreFoundation                      0x02c51f4b __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 27
    22  CoreFoundation                      0x02be6b27 __CFRunLoopDoObservers + 295
    23  CoreFoundation                      0x02bafce7 __CFRunLoopRun + 1575
    24  CoreFoundation                      0x02baf350 CFRunLoopRunSpecific + 208
    25  CoreFoundation                      0x02baf271 CFRunLoopRunInMode + 97
    26  GraphicsServices                    0x0318000c GSEventRunModal + 217
    27  GraphicsServices                    0x031800d1 GSEventRun + 115
    28  UIKit                               0x0033baf2 UIApplicationMain + 1160
    29  MyNewbieApp                         0x00002034 main + 102
    30  MyNewbieApp                         0x00001fc5 start + 53
)
terminate called after throwing an instance of 'NSException'

所以它的Index数组越界异常.我没有任何有3个元素的NSMutableArray.我的所有阵列都要大得多.啊,异常从这里出来:

    - (void)downloadDidFinishDownloading:(Meeting *)meeting
    {
        NSLog(@"downloadDidFinishDownloading %@",meeting.cellPath);
        //NSLog(@"downloadDidFinishDownloading meeting.cellPath =  [row = %d,section = %d]",meeting.cellPath.row,meeting.cellPath.section);

        [self.tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:meeting.cellPath] withRowAnimation:UITableViewRowAnimationNone];
        meeting.delegate = nil;
    }

- (void)download:(Meeting *)meeting didFailWithError:(NSError *)error{
    [self downloadDidFinishDownloading:meeting];
}

每次会议图像DLing完成后,都会调用此回调方法.如果我只是用reloadRowsAtIndexPaths评论代码行 - 一切正常.否则我会收到错误.什么可以呢？我花了很多时间,但它没用了......我只是没有胶水什么都有...而且当我滚动桌子的内容时,问题更加奇怪,问题总是出现在第5个元素:) .并且第5个元素没有什么特别之处,我已经尝试了另一个数据集,但问题仍然存在.

更新:仅当代码回调download:(Meeting *)meeting didFailWithError方法时才会发生错误/崩溃.但它仍然有相同的会议参数,我发送给downloadDidFinishDownloading.我也试过以下:

    - (void)download:(Meeting *)meeting didFailWithError:(NSError *)error{
[self.tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:meeting.cellPath] withRowAnimation:UITableViewRowAnimationNone];
            meeting.delegate = nil;
}

所以应用程序现在仅在reloadRowsAtIndexPaths中的此方法中崩溃.

Answer 1

一个想法是，您可能需要更新数据源对象“tableDataSource”，尤其是部分中的行数

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section

编辑 ：

进一步阅读您的问题，您可以复制粘贴 cellForRowAtIndexPath 中的“可重用单元格”部分吗（实际上是整个方法，我猜问题就在那里）