我想從JSON解析對象後填充表視圖。我想將行數設置爲解析對象的數量。NSRangeException錯誤
這裏是我的viewDidLoad代碼:
- (void)viewDidLoad
{
[super viewDidLoad];
// initializing data source
[self setNotifications:[[NSMutableArray alloc] init]];
NSURL *url = [NSURL URLWithString:SourceURL];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
[self setNotifications:[JSON objectForKey:@"notifications"]];
// [[self tableView] setHidden:NO];
[[self tableView] reloadData];
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
NSLog(@"Request Failure Because %@",[error userInfo]);
}];
[operation start];
}
這裏是我的數據源的方法之一(我相信,誤差必須在這裏):
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if ([self notifications] && [[self notifications] count]) {
return [[self notifications] count];
} else{
return 0;
}
}
這裏是我的全部錯誤消息:
> *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayI objectAtIndex:]: index 1 beyond bounds [0 ..
> 0]'
> *** First throw call stack: (0x13c4012 0x118ce7e 0x1379b44 0x510c04 0x300ea0 0x2b5c4e 0x2b8224 0x17c952 0x17c2dc 0xc4a9d14 0x26e0 0x16ea2
> 0x18409 0x162753f 0x1639014 0x16297d5 0x136aaf5 0x1369f44 0x1369e1b
> 0x22647e3 0x2264668 0xd0ffc 0x1f1d 0x1e45) libc++abi.dylib: terminate
> called throwing an exception
UPDATE:
這裏是我的cellForRowAtIndexPath方法:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellID = @"readNotification";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellID];
if (!cell){
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellID];
}
NSDictionary *notification = [[self notifications] objectAtIndex:[indexPath row]];
[[cell textLabel] setText:[notification objectForKey:@"from"]];
[[cell detailTextLabel] setText:[notification objectForKey:@"date"]];
return cell;
}
更新2
我加了一些日誌項目,它提供了一些有趣的輸出:
2013-08-06 23:53:03.994 NotificationReader [1193:c07] 1.請求前 2013-08-06 23:53:04.023 NotificationReader [1193:c07] 2. json parshing 運行開始2013-08-06 23:53:04.031 NotificationReader [1193:c07] 3.輸入numberOfRowsInSection塊2013-08-06 23:53:04.040 NotificationReader [1193:c07]無通知2013-08-06 23:53:04.319 NotificationReader [1193 :c07] 3.輸入numberOfRowsInSection block 2013-08-06 23:53:04.320 NotificationReader [1193:c07]有 14通知2013-08-06 23:53:08.260 NotificationReader [1193:c07] *由於未捕獲的異常而終止應用程序
所以首先它認爲我的數組是空的,然後重新加載並獲得正確的通知計數。不幸的是,它從未進入的cellForRowAtIndexPath方法..
更新3
我增加了一個異常斷點到我的項目,再加上做了一些額外的日誌記錄,和我假設,它在某種程度上有麻煩重裝表視圖。這是迄今爲止的效果:
2013-08-07 08:40:58.104 NotificationReader[433:c07] 1. before request
2013-08-07 08:40:58.107 NotificationReader[433:c07] 2. json parshing operation started
2013-08-07 08:40:58.113 NotificationReader[433:c07] 3. entered the numberOfRowsInSection block
2013-08-07 08:40:58.120 NotificationReader[433:c07] Found 0 notifications!
2013-08-07 08:41:10.852 NotificationReader[433:c07] Trying to reload data
2013-08-07 08:41:10.853 NotificationReader[433:c07] data needs to be reloaded
2013-08-07 08:41:10.854 NotificationReader[433:c07] 3. entered the numberOfRowsInSection block
2013-08-07 08:41:10.855 NotificationReader[433:c07] Found 14 notifications!
2013-08-07 08:41:10.858 NotificationReader[433:c07] *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayI objectAtIndex:]: index 1 beyond bounds [0 .. 0]'
*** First throw call stack:
(0x13c5012 0x118de7e 0x137ab44 0x511c04 0x301ea0 0x2b6c4e 0x2b9224 0x17d952 0x17d2dc 0xc4c0d14 0x351b 0x162853f 0x163a014 0x162a7d5 0x136baf5 0x136af44 0x136ae1b 0x22657e3 0x2265668 0xd1ffc 0x2c4d 0x2b75)
libc++abi.dylib: terminate called throwing an exception}
堆棧跟蹤:
#0 0x0118de52 in objc_exception_throw()
#1 0x0137ab44 in -[__NSArrayI objectAtIndex:]()
#2 0x00511c04 in -[UITableViewDataSource tableView:heightForRowAtIndexPath:]()
#3 0x00301ea0 in -[UITableViewController tableView:heightForRowAtIndexPath:]()
#4 0x002b6c4e in -[UISectionRowData refreshWithSection:tableView:tableViewRowData:]()
#5 0x002b9224 in -[UITableViewRowData numberOfRows]()
#6 0x0017d952 in -[UITableView noteNumberOfRowsChanged]()
#7 0x0017d2dc in -[UITableView reloadData]()
#8 0x0c4a9d14 in -[UITableViewAccessibility(Accessibility) reloadData]()
#9 0x0000351b in __36-[NRTableViewController viewDidLoad]_block_invoke_2 at /Users/jozsef/Development/NotificationReader/NotificationReader/NRTableViewController.m:52
我嘗試使用LLDB這個結果:
(lldb) po [[self notifications] count]
error: Execution was interrupted, reason: Attempted to dereference an invalid pointer..
The process has been returned to the state before execution.
這種方法可以簡化爲' - (NSInteger的)的tableView: (UITableView *)tableView numberOfRowsInSection:(NSInteger)部分 { return [[self notifications] count]; }'具有完全相同的效果,並且不能在任何情況下導致該異常。正如消息所說,這是對「objectAtIndex:」的調用,其參數1正在提高。 –
你可以在你的UITableViewDelegate方法中放置斷點並找出引發異常的那一行嗎? 您的'numberOfRowsInSection'委託似乎沒有任何問題。 –
@Tarek我在viewDidLoad方法的頂部初始化通知。 –