removeobjectAtIndex：使索引为-1；

Question

我有一个 NSTableView，它由一个名为 tableArray 的数组填充。我有一个按钮应该从数组中删除所选项目。在我的 removeItem: 方法中：

[tableArray removeObjectAtIndex:[tableView selectedRow];
[tableView reloadData];

但我收到错误消息：

2015-05-13 18:16:45.283 FileShedb1.0[979:303] *** -[__NSArrayM objectAtIndex:]: index 18446744073709551615 beyond bounds [0 .. 0]
2015-05-13 18:16:45.288 FileShedb1.0[979:303] (
    0   CoreFoundation                      0x00007fff8d35ff56 __exceptionPreprocess + 198
    1   libobjc.A.dylib                     0x00007fff93119d5e objc_exception_throw + 43
    2   CoreFoundation                      0x00007fff8d2ed392 -[__NSArrayM objectAtIndex:] + 274
    3   FileShedb1.0                        0x00000001000028a9 -[MPOMainWindowController tableViewSelectionDidChange:] + 201
    4   Foundation                          0x00007fff8cca0d0e __-[NSNotificationCenter addObserver:selector:name:object:]_block_invoke_1 + 47
    5   CoreFoundation                      0x00007fff8d3087ba _CFXNotificationPost + 2634
    6   Foundation                          0x00007fff8cc8cfc3 -[NSNotificationCenter postNotificationName:object:userInfo:] + 65
    7   AppKit                              0x00007fff8ab10049 -[NSTableView _sendSelectionChangedNotificationForRows:columns:] + 203
    8   AppKit                              0x00007fff8aae6b0a -[NSTableView _enableSelectionPostingAndPost] + 425
    9   AppKit                              0x00007fff8aadcd75 -[NSTableView _tileAndRedisplayAll] + 358
    10  FileShedb1.0                        0x00000001000027bc -[MPOMainWindowController removeFile:] + 188
    11  CoreFoundation                      0x00007fff8d34f70d -[NSObject performSelector:withObject:] + 61
    12  AppKit                              0x00007fff8aaa98ca -[NSApplication sendAction:to:from:] + 139
    13  AppKit                              0x00007fff8aaa97fe -[NSControl sendAction:to:] + 88
    14  AppKit                              0x00007fff8aaa9729 -[NSCell _sendActionFrom:] + 137
    15  AppKit                              0x00007fff8aaa8bec -[NSCell trackMouse:inRect:ofView:untilMouseUp:] + 2014
    16  AppKit                              0x00007fff8ab28b74 -[NSButtonCell trackMouse:inRect:ofView:untilMouseUp:] + 489
    17  AppKit                              0x00007fff8aaa77f6 -[NSControl mouseDown:] + 786
    18  AppKit                              0x00007fff8aa72c98 -[NSWindow sendEvent:] + 6306
    19  AppKit                              0x00007fff8aa0c3a5 -[NSApplication sendEvent:] + 5593
    20  AppKit                              0x00007fff8a9a2a0e -[NSApplication run] + 555
    21  AppKit                              0x00007fff8ac1eeac NSApplicationMain + 867
    22  FileShedb1.0                        0x00000001000014c2 main + 34
    23  FileShedb1.0                        0x0000000100001494 start + 52
)

有人知道我为什么会收到错误消息吗？

Answer 1

如果没有选择行，selectedRow行returns-1。检查一下。

Checkout apple's documentation.

removeobjectAtIndex：使索引为-1；

removeobjectAtIndex: causes index to be -1;

macos

xcode

cocoa

nstableview

nsmutablearray