终止所谓的“NSException”
问题描述:
我尝试运行我的应用程序,但我有抛出异常,在控制台中我有这样的:终止所谓的“NSException”
2011-05-05 00:18:50.984 myApp[2906:207] *** Terminating app due to uncaught exception 'NSGenericException', reason: '*** Collection <__NSArrayM: 0x6b8b780> was mutated while being enumerated.(
"<MyLocation: 0x6b67af0>",
"<MyLocation: 0x6b19360>",
"<MyLocation: 0x6b67a70>",
"<MyLocation: 0x6b8d110>",
"<MyLocation: 0x6b8d280>",
"<MyLocation: 0x6b8ce50>",
"<MyLocation: 0x6b8d660>"
)'
*** Call stack at first throw:
(
0 CoreFoundation 0x02915919 __exceptionPreprocess + 185
1 libobjc.A.dylib 0x0272a5de objc_exception_throw + 47
2 CoreFoundation 0x029153d9 __NSFastEnumerationMutationHandler + 377
3 myApp 0x00005755 -[StationsSurLaCarteViewController requestFinished:] + 343
4 myApp 0x000195cb -[ASIHTTPRequest reportFinished] + 171
5 Foundation 0x000abe9a __NSThreadPerformPerform + 251
6 CoreFoundation 0x028f6d7f __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 15
7 CoreFoundation 0x028552cb __CFRunLoopDoSources0 + 571
8 CoreFoundation 0x028547c6 __CFRunLoopRun + 470
9 CoreFoundation 0x02854280 CFRunLoopRunSpecific + 208
10 CoreFoundation 0x028541a1 CFRunLoopRunInMode + 97
11 GraphicsServices 0x02e8e2c8 GSEventRunModal + 217
12 GraphicsServices 0x02e8e38d GSEventRun + 115
13 UIKit 0x0033ab58 UIApplicationMain + 1160
14 myApp 0x0000224c main + 102
15 myApp 0x000021dd start + 53
)
terminate called after throwing an instance of 'NSException'
Program received signal: “SIGABRT”.
(gdb)
我注意到,我得到了自我尝试使用标注为我的地图视图,请帮助,THX提前:)
编辑
这是我for
循环,可以使问题:
for (int i=0; i<[array count]; i++) {
NSDictionary *stationEnCours=[array objectAtIndex:i];
NSString *distance=[stationEnCours objectForKey:@"distance"];
float lng = [[stationEnCours objectForKey:@"ssiphone_longitude"] floatValue];
float lat = [[stationEnCours objectForKey:@"ssiphone_latitude"] floatValue];
NSString *ensStation=[stationEnCours objectForKey:@"ssiphone_enseigne"];
location2D = (CLLocationCoordinate2D){ .latitude = lat, .longitude = lng };
MyLocation *annotation=[[[MyLocation alloc]initWithName:ensStation distanceVersLaStation:distance coordinate:location2D]autorelease];
[mapView addAnnotation:annotation];
MKCoordinateSpan span={latitudeDelta:0.2,longitudeDelta:0.2};
MKCoordinateRegion region={location2D,span};
[mapView setRegion:region];
[self.view addSubview:mapView];
}`
答
您例外的给定原因是“集合...被列举时发生了变化”。这意味着您试图更改for(in)
循环内的数组,这是不允许的,因为它会更改您应该枚举的对象。原因的结尾是您正在枚举的数组的转储。它包含7个MyLocation
对象。如果您查看调用堆栈的顶部,您会发现异常发生在您的-[StationsSurLaCarteViewController requestFinished:]
方法中。如果您仔细查看该方法并找到使用快速枚举的地方,则应该很容易找到问题所在。
如果要在使用快速枚举的同时修改数组,则有两种可能性:跟踪要更改的所有内容(即要删除的索引列表)并在循环后进行更改,或者请在数组的副本上进行枚举。这里是第二种方法的例子:
NSArray *copiedArray = [originalArray copy];
for(id theObject in copiedArray) {
if([theObject shouldBeDeleted]) {
[originalArray removeObject:theObject];
}
}
[copiedArray release];
NSArray *copiedArray = [originalArray copy];
for(id theObject in copiedArray) {
if([theObject shouldBeDeleted]) {
[originalArray removeObject:theObject];
}
}
[copiedArray release];
嗨,请看看我的编辑,我看不到'for'loop有什么问题,我是否缺少内存管理? – Luca 2011-05-05 11:48:09
你确定循环导致崩溃吗?你正在寻找的那个应该使用'for(in)'语法,并且改变以'in'命名的数组。如果该循环是问题,那么另一个循环运行在另一个也是负责的线程中。 – ughoavgfhw 2011-05-05 16:47:57