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通过从属性列表中读取的nsdictionary循环,带来麻烦

property-list mkmapview annotations ios

0

Stunner · 技术社区 · 15 年前

嘿,伙计们,我在读一篇文章,结构像这样:

如您所见,它是一个包含不同类型(C,访问者)注释信息的plist。我可以很好地显示每个注释类型,但我正试图循环显示所有类型,并同时在地图视图上显示所有注释。代码如下:

nslog(@“LoadAnnotations”);
nsstring*plistpath=[[nsbundle mainbundle]pathforresource:@“permitdata”of type:@“plist”];
nsdictionary*rootofPermitDataplistDict=[[nsdictionary alloc]initWithContentsOfFile:plistPath];
//nsmutabledictionary*permitdict=[[nsmutabledictionary alloc]init];
if([自标题]=@“所有许可证”)。{
for(rootofPermitDataplistDict中的ID键){
nslog(@“key:%@”,key);

// [密钥保留];
nsmutabledictionary*permitdict=[nsdictionary dictionary withdictionary:[rootofpermitDataplistdict objectfookey:key]];
//[钥匙释放];

//包含注释信息的数组:纬度、经度、标题、副标题(请参见permitdata.plist)
nsarray*annotationsarray=[[nsarray alloc]initWithArray:[permitdict objectfookey:@“annotations”]];
【许可放行】;
[rootofPermitDataplistDict发布];

cllocationCoordinate2d工作坐标;
nsdictionary*annotationcontainerdict=[[nsdictionary alloc]init];
//循环遍历annotations数组,创建包含plist中的信息的驻车注释
用于(AnnotationContainerDict in AnnotationsArray){
nslog(@“%@”,annotationContainerDict);

parkingannotation*parkingannot=[[parkingannotation alloc]init];
workingCoordinate.Latitude=[[AnnotationContainerDict Objectfookey:@“Latitude”]DoubleValue];
workingcoordinate.longitude=[[annotationContainerDict Objectfookey:@“longitude”]doubleValue];
[停车场设置坐标:工作坐标];
[parkingannot settitle:[批注容器dict对象分叉:@“标题”];
[parkinganot setsubtitle:[注释容器dict objectforkey:@“subtitle”];
if([ParkinganNot Title]==@“C Parking”)[ParkinganNot SetAnnotationType:AnnotationTypeC];
else if([ParkingAnnot title]==@“访客停车场”)[ParkingAnnot setAnnotationType:AnnotationTypeVisitor];
[MapView AddAnnotation:帕金森氏病];
[帕金森不缓解];
}
【许可放行】;
}
}
< /代码> 

这是我运行程序时的控制台输出:

2010-11-25 03:25:28.020 parking[38918:207]all permits
2010-11-25 03:25:28.021停车[38918:207]装载注释
2010-11-25 03:25:28.021停车[38918:207]键:C
2010-11-25 03:25:28.021停车场[38918:207]{
纬度=“38.545301”;
经度=“-121.754066”;
subtitle=“副总裁17”;
title=“C停车”;
}








NSLog(@"loadAnnotations");
NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"PermitData" ofType:@"plist"];
NSDictionary *rootOfPermitDataPlistDict = [[NSDictionary alloc] initWithContentsOfFile:plistPath];
// NSMutableDictionary *permitDict = [[NSMutableDictionary alloc] init];
 if ([self title] == @"All Permits") {
  for (id key in rootOfPermitDataPlistDict) {
   NSLog(@"key:%@",key);

   //[key retain];
   NSMutableDictionary *permitDict = [NSDictionary dictionaryWithDictionary:[rootOfPermitDataPlistDict objectForKey:key]];
   //[key release];

   //array containing annotation information: latitude, longitude, title, subtitle(see PermitData.plist)
   NSArray *annotationsArray = [[NSArray alloc] initWithArray:[permitDict objectForKey:@"annotations"]];
   [permitDict release];
   [rootOfPermitDataPlistDict release];

   CLLocationCoordinate2D workingCoordinate;
   NSDictionary *annotationContainerDict = [[NSDictionary alloc] init];
   //loop through annotations array, creating parking annotations filled with the information found in the plist
   for(annotationContainerDict in annotationsArray){
    NSLog(@"%@",annotationContainerDict);

    ParkingAnnotation *parkingAnnot = [[ParkingAnnotation alloc] init];
    workingCoordinate.latitude = [[annotationContainerDict objectForKey:@"latitude"] doubleValue];
    workingCoordinate.longitude = [[annotationContainerDict objectForKey:@"longitude"] doubleValue];
    [parkingAnnot setCoordinate:workingCoordinate];
    [parkingAnnot setTitle:[annotationContainerDict objectForKey:@"title"]];
    [parkingAnnot setSubtitle:[annotationContainerDict objectForKey:@"subtitle"]];
    if ([parkingAnnot title] == @"C Parking") [parkingAnnot setAnnotationType:annotationTypeC];
    else if ([parkingAnnot title] == @"Visitor Parking") [parkingAnnot setAnnotationType:annotationTypeVisitor];
    [mapView addAnnotation:parkingAnnot];
    [parkingAnnot release];
   }
   [permitDict release];
  }
 }




2010-11-25 03:25:28.020 Parking[38918:207] All Permits
2010-11-25 03:25:28.021 Parking[38918:207] loadAnnotations
2010-11-25 03:25:28.021 Parking[38918:207] key:C
2010-11-25 03:25:28.021 Parking[38918:207] {
    latitude = "38.545301";
    longitude = "-121.754066";
    subtitle = "VP 17";
    title = "C Parking";
}
2010-11-25 03:25:28.022 Parking[38918:207] {
    latitude = "38.544831";
    longitude = "-121.754785";
    subtitle = "VP 16";
    title = "C Parking";
}
2010-11-25 03:25:28.022 Parking[38918:207] {
    latitude = "38.544781";
    longitude = "-121.755729";
    subtitle = "VP 22";
    title = "C Parking";
}
2010-11-25 03:25:28.022 Parking[38918:207] {
    latitude = "38.544412";
    longitude = "-121.752489";
    subtitle = "VP 15";
    title = "C Parking";
}








2010-11-25 20:28:08.141 Parking[39400:207] All Permits
2010-11-25 20:28:08.142 Parking[39400:207] loadAnnotations
2010-11-25 20:28:08.142 Parking[39400:207] key:C
2010-11-25 20:28:08.143 Parking[39400:207] {
    latitude = "38.545301";
    longitude = "-121.754066";
    subtitle = "VP 17";
    title = "C Parking";
}
2010-11-25 20:28:08.143 Parking[39400:207] {
    latitude = "38.544831";
    longitude = "-121.754785";
    subtitle = "VP 16";
    title = "C Parking";
}
2010-11-25 20:28:08.143 Parking[39400:207] {
    latitude = "38.544781";
    longitude = "-121.755729";
    subtitle = "VP 22";
    title = "C Parking";
}
2010-11-25 20:28:08.144 Parking[39400:207] {
    latitude = "38.544412";
    longitude = "-121.752489";
    subtitle = "VP 15";
    title = "C Parking";
}
2010-11-25 20:28:08.145 Parking[39400:207] *** Terminating app due to uncaught exception 'NSGenericException', reason: '*** Collection <__NSCFDictionary: 0x6d5fd80> was mutated while being enumerated.<CFBasicHash 0x6d5fd80 [0x2667380]>{type = mutable dict, count = 1,
entries =>
    0 : <0x7380> = <NSKeyValueContainerClass: Original class: ParkingAnnotation, Notifying class: NSKVONotifying_ParkingAnnotation>
}
'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x025fdb99 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x0274d40e objc_exception_throw + 47
    2   CoreFoundation                      0x025fd659 __NSFastEnumerationMutationHandler + 377
    3   Parking                             0x00002e93 -[ParkingMapViewController loadAnnotations] + 364
    4   Parking                             0x00002caf -[ParkingMapViewController viewDidLoad] + 117
    5   UIKit                               0x0036a5ca -[UIViewController view] + 179
    6   UIKit                               0x003689f4 -[UIViewController contentScrollView] + 42
    7   UIKit                               0x003787e2 -[UINavigationController _computeAndApplyScrollContentInsetDeltaForViewController:] + 48
    8   UIKit                               0x00376ea3 -[UINavigationController _layoutViewController:] + 43
    9   UIKit                               0x00378067 -[UINavigationController _startTransition:fromViewController:toViewController:] + 326
    10  UIKit                               0x00372ccd -[UINavigationController _startDeferredTransitionIfNeeded] + 266
    11  UIKit                               0x00379d8b -[UINavigationController pushViewController:transition:forceImmediate:] + 876
    12  UIKit                               0x00372b67 -[UINavigationController pushViewController:animated:] + 62
    13  Parking                             0x00002914 -[PermitListViewController tableView:didSelectRowAtIndexPath:] + 307
    14  UIKit                               0x00333a48 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1140
    15  UIKit                               0x0032a32e -[UITableView _userSelectRowAtIndexPath:] + 219
    16  Foundation                          0x0003f21a __NSFireDelayedPerform + 441
    17  CoreFoundation                      0x025def73 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 19
    18  CoreFoundation                      0x025e05b4 __CFRunLoopDoTimer + 1364
    19  CoreFoundation                      0x0253cdd9 __CFRunLoopRun + 1817
    20  CoreFoundation                      0x0253c350 CFRunLoopRunSpecific + 208
    21  CoreFoundation                      0x0253c271 CFRunLoopRunInMode + 97
    22  GraphicsServices                    0x02edc00c GSEventRunModal + 217
    23  GraphicsServices                    0x02edc0d1 GSEventRun + 115
    24  UIKit                               0x002ceaf2 UIApplicationMain + 1160
    25  Parking                             0x00001e08 main + 102
    26  Parking                             0x00001d99 start + 53
)
terminate called after throwing an instance of 'NSException'

2 回复 | 直到 15 年前

1

4

Community Mohan Dere 9 年前

代码崩溃有两个主要原因。

弗斯特 ,此行位于for循环内:

[rootOfPermitDataPlistDict release];

销毁当前正在循环访问的对象。移动到最末端——在 if ([self title]... 语句。

第二 ,这两行表示:

[permitDict release];

应该移除。不要释放permitdict,因为您正在使用返回自动释放对象的DictionaryWithDictionary创建它。

有了这两个更改,代码就可以运行了。

然而 ,还有一些其他问题:

你分配+ init annotationsArray 但千万不要释放它(内存泄漏)。在经过该数组的for循环之后释放它(在该数组中,当前有第二个 [permitDict release]; )
你分配+ init annotationContainerDict 但是,然后只将变量用作AnnotationsArray中对象的引用(因此放弃分配的内存——内存泄漏)。不要费心在annotationContainerDict上执行alloc+init,只要声明它。变化 NSDictionary *annotationContainerDict = [[NSDictionary alloc] init]; 只是 NSDictionary *annotationContainerDict; .
您正在使用比较字符串 == . 使用 isEqualToString: 而是这样:
if ([[self title] isEqualToString:@"All Permits"])... . 为了解释为什么你应该使用 isEqualToString 见 this question 和 this question .
这里并不是一个很严重的问题,但是没有必要使用字典和字典,从而复制根目录中已经存在的内容。您可以使用permitdict作为对嵌入式词典的简写引用,如下所示: NSMutableDictionary *permitDict = [rootOfPermitDataPlistDict objectForKey:key]; .
与annotationsarray相同:您不需要分配+init一个新数组。数组已位于rootofPermitDataplistDict中。只需这样引用: NSArray *annotationsArray = [permitDict objectForKey:@"annotations"]; . 如果您决定这样做,请不要发布注释。

这个 Memory Management Programming Guide 详细解释了这一切。

2

1

NSGod Luchian Grigore 15 年前

首先,您的代码有很多问题,但是除非这是性能关键的代码,否则您将每秒循环数百次(可能会创建许多自动释放的对象),使用alloc]init]方法只会使代码更难执行。(因为你必须在精神上经历并不断地平衡一个分配与一个释放)。别误会我,重要的是你要理解保留和释放等,但这是我解决问题的方法。

记住你在控制之中。使您的停车注释类能够“独立思考”一点。在下面的示例中,我添加了一个-(ID)initWithDictionary:这样您的另一个类就不必坐在那里一个接一个地设置键了。(有一些虚构的部分,我假设你会填补空白…

NSString * const PPAnnotationsKey   = @"annotations";
NSString * const PPTitleKey         = @"title";
NSString * const PPSubtitleKey      = @"subtitle";
NSString * const PPLatitudeKey      = @"latitude";
NSString * const PPLongitudeKey     = @"longitude";

NSLog(@"loadAnnotations");
NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"PermitData" ofType:@"plist"]; // autoreleased
NSDictionary *permitDictionary = [NSDictionary dictionaryWithContentsOfFile:plistPath]; // autoreleased
if ([[self title] isEqualToString:@"All Permits"]) {
    for (NSString *parkingGroup in permitDictionary) {
        NSLog(@"parkingGroup == %@", parkingGroup);
        NSArray *annotations = [parkingGroup objectForKey:PPAnnotationsKey];
        for (NSDictionary *entry in annotations) {
            PPParkingAnnotation *annotation = [PPParkingAnnotation parkingAnnotationWithDictionary:entry]; // autoreleased
            if (annotation) {
            // assuming here that mapView's addAnnotation: will retain the
            // annotation
            [mapView addAnnotation:annotation]; 
            }
        }
    }
}

@interface PPParkingAnnotation : NSObject <MKAnnotation> {
    CLLocationCoordinate2D   coordinate;
    NSString                *title;
    NSString                *subtitle;
}
+ (id)parkingAnnotationWithDictionary:(NSDictionary *)dictionary;
- (id)initWithDictionary:(NSDictionary *)dictionary;

@properties...
@end

@implementation PPParkingAnnotation

+ (id)parkingAnnotationWithDictionary:(NSDictionary *)dictionary {
    return [[[[self class] alloc] initWithDictionary:dictionary] autorelease];
}

- (id)initWithDictionary:(NSDictionary *)dictionary {
    [self setTitle:[dictionary objectForKey:PPTitleKey]];
    [self setSubtitle:[dictionary objectForKey:PPTitleKey]];
    // and so on.
}