我有一个NSOutlineView，我为其执行reloadData：
[myOutlineView reloadData];
myOutlineView是从InterfaceBuilder绑定的。这在我的计算机上工作正常，但不适用于我无法访问的机器的beta测试人员 他的崩溃日志显示：
Application Specific Information:
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '_rowViews should not be NULL at this point'
terminating with uncaught exception of type NSException
abort() called
Application Specific Backtrace 1:
0 CoreFoundation 0x00007fff888fd66c __exceptionPreprocess + 172
1 libobjc.A.dylib 0x00007fff8f1e376e objc_exception_throw + 43
2 CoreFoundation 0x00007fff888fd44a +[NSException raise:format:arguments:] + 106
3 Foundation 0x00007fff8ba8e3a9 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 195
4 AppKit 0x00007fff85e54b24 -[NSTableRowData _removeRowViewForRow:] + 472
5 AppKit 0x00007fff85d3e0dd -[NSTableRowData _removeVisibleRows] + 93
6 AppKit 0x00007fff85d3dd4a -[NSTableRowData removeAllKnownSubviews] + 139
7 AppKit 0x00007fff85d3dafb -[NSTableRowData reloadData] + 74
8 AppKit 0x00007fff85d3d968 -[NSTableView reloadData] + 175
9 AppKit 0x00007fff85efb77c -[NSOutlineView reloadData] + 578
10 PhotoStream2Folder 0x0000000105b668d1 -[PSFAppDelegate scanSharedStreams] + 2249
我可以做些什么来进一步理解为什么_rowViews为零？
如何在启动reloadData之前测试_rowViews？
感谢