Can'；t访问对象'；objective-c中的s性质

我刚跳进Objective-C，很早就被卡住了。我会用我的问题发布代码，但为了保持可读性，我会去掉一些垃圾，如果你想发布更多代码，请告诉我

我已经创建了一个名为“短语”的新对象（从NSObject子类化），并且正在将JSON中的项读取到这些“短语”对象中，并将它们添加到一个数组中。以下是第一批代码：

示例JSON:

    {
    "phrases": [
        {
            "title": "Title of my Phrase",
         "definition" : "A way to look at some words",
   "location" : "Irish Proverb"
        }   
    ]
    }

    - (void)viewDidLoad {
    [super viewDidLoad];

 self.phraseDictionary = [[NSMutableArray alloc] initWithObjects:nil];

 NSString *filePath = [[NSBundle mainBundle] pathForResource:@"phrase" ofType:@"json"];  
 NSString *myRawJSON = [[NSString alloc] initWithContentsOfFile:filePath];

 NSData *jsonData = [myRawJSON dataUsingEncoding:NSUTF32BigEndianStringEncoding];
 NSDictionary *entries = [[CJSONDeserializer deserializer] deserializeAsDictionary:jsonData error:nil];


 for (id key in entries) {

  NSObject *phrases = [entries objectForKey:key];

  for (id phrase in phrases) {

   Phrase *pushArrayToPhrase = [[Phrase alloc] initWithText:[phrase objectForKey:@"title"] definition:[phrase objectForKey:@"definition"] location:[phrase objectForKey:@"location"]];
   [self.phraseDictionary addObject:pushArrayToPhrase];

  }

    }
    }

#import "Phrase.h"


@implementation Phrase

@synthesize title;
@synthesize definition;
@synthesize location;

- (id)init {
 self = [super init];
 if (self != nil) {
  title = @"";
  definition = @"";
  location = @"";
 }
 return self;
}

- (id)initWithTitle:(NSString *)tit definition:(NSString *)def location:(NSString *)loc {
 self = [super init];
 if (self != nil) {
  title = tit;
  definition = def;
  location = loc;
 } 
 return self;
}


@end

我正在阅读的脚本：

    {
    "phrases": [
        {
            "title": "Title of my Phrase",
         "definition" : "A way to look at some words",
   "location" : "Irish Proverb"
        }   
    ]
    }

    - (void)viewDidLoad {
    [super viewDidLoad];

 self.phraseDictionary = [[NSMutableArray alloc] initWithObjects:nil];

 NSString *filePath = [[NSBundle mainBundle] pathForResource:@"phrase" ofType:@"json"];  
 NSString *myRawJSON = [[NSString alloc] initWithContentsOfFile:filePath];

 NSData *jsonData = [myRawJSON dataUsingEncoding:NSUTF32BigEndianStringEncoding];
 NSDictionary *entries = [[CJSONDeserializer deserializer] deserializeAsDictionary:jsonData error:nil];


 for (id key in entries) {

  NSObject *phrases = [entries objectForKey:key];

  for (id phrase in phrases) {

   Phrase *pushArrayToPhrase = [[Phrase alloc] initWithText:[phrase objectForKey:@"title"] definition:[phrase objectForKey:@"definition"] location:[phrase objectForKey:@"location"]];
   [self.phraseDictionary addObject:pushArrayToPhrase];

  }

    }
    }

#import "Phrase.h"


@implementation Phrase

@synthesize title;
@synthesize definition;
@synthesize location;

- (id)init {
 self = [super init];
 if (self != nil) {
  title = @"";
  definition = @"";
  location = @"";
 }
 return self;
}

- (id)initWithTitle:(NSString *)tit definition:(NSString *)def location:(NSString *)loc {
 self = [super init];
 if (self != nil) {
  title = tit;
  definition = def;
  location = loc;
 } 
 return self;
}


@end

短语m文件：

    {
    "phrases": [
        {
            "title": "Title of my Phrase",
         "definition" : "A way to look at some words",
   "location" : "Irish Proverb"
        }   
    ]
    }

    - (void)viewDidLoad {
    [super viewDidLoad];

 self.phraseDictionary = [[NSMutableArray alloc] initWithObjects:nil];

 NSString *filePath = [[NSBundle mainBundle] pathForResource:@"phrase" ofType:@"json"];  
 NSString *myRawJSON = [[NSString alloc] initWithContentsOfFile:filePath];

 NSData *jsonData = [myRawJSON dataUsingEncoding:NSUTF32BigEndianStringEncoding];
 NSDictionary *entries = [[CJSONDeserializer deserializer] deserializeAsDictionary:jsonData error:nil];


 for (id key in entries) {

  NSObject *phrases = [entries objectForKey:key];

  for (id phrase in phrases) {

   Phrase *pushArrayToPhrase = [[Phrase alloc] initWithText:[phrase objectForKey:@"title"] definition:[phrase objectForKey:@"definition"] location:[phrase objectForKey:@"location"]];
   [self.phraseDictionary addObject:pushArrayToPhrase];

  }

    }
    }

#import "Phrase.h"


@implementation Phrase

@synthesize title;
@synthesize definition;
@synthesize location;

- (id)init {
 self = [super init];
 if (self != nil) {
  title = @"";
  definition = @"";
  location = @"";
 }
 return self;
}

- (id)initWithTitle:(NSString *)tit definition:(NSString *)def location:(NSString *)loc {
 self = [super init];
 if (self != nil) {
  title = tit;
  definition = def;
  location = loc;
 } 
 return self;
}


@end

从这里，我循环浏览对象并将其添加到splitview中的列表中：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

 static NSString *CellIdentifier = @"CellIdentifier";

 // Dequeue or create a cell of the appropriate type.
 UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
        cell.accessoryType = UITableViewCellAccessoryNone;
    }

    Phrase *cellPhrase = [self.phraseDictionary objectAtIndex:indexPath.row];
 cell.textLabel.text = cellPhrase.title;
 return cell;
}

但是，当我单击一个项目，并根据单击的项目的indexPath.row请求短语时，我只能访问cell.textlab.text中使用的属性。从此处开始，从短语对象访问属性的任何其他尝试都将退出模拟器

- (void)tableView:(UITableView *)aTableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

 Phrase *cellPhrase = [self.phraseDictionary objectAtIndex:indexPath.row];
 detailViewController.detailItem = cellPhrase;
 //If i attempt 'cellPhrase.definition' here, the app will close without an error

}

---

希望这是容易遵循，让我知道如果不是，我会再试一次

在initWithTitle方法中，您分配变量，但不保留它们。如果它们没有保留在任何地方，它们将被释放，当你试图访问它们时，你的应用程序将崩溃。如果没有收到任何错误消息，请确保打开调试。

有任何信息说明它存在的原因吗？你检查过日志了吗？正如我刚才在下面发布的，当我打开调试时，我收到了这个“程序接收信号：“EXC_BAD_ACCESS”。我看到了这个链接，但无法将其与我的情况联系起来……你所说的分配但不保留是什么意思？（我对这一点还不熟悉，所以仍在考虑分配/保留等问题）-我的头衔=乳头；definition=def等在initWithTitle方法中，我是否需要以不同的方式执行此操作？另外-我打开了调试，并收到“程序接收信号：“EXC\u BAD\u ACCESS”。“当您执行title=tit；没有任何东西可以阻止字符串保留的内存稍后被释放。因此，下次尝试访问字符串时，程序将崩溃，因为内存不再有效。要防止出现这种情况，请尝试title=[tit retain]；或者如果你的财产是保留的，你可以做self.title=tit；然后在您的dealloc方法中执行[标题发布]；以确保稍后清除内存。谢谢堆，这就成功了。你对objective-c中关于内存管理/保留等方面的阅读有什么建议，甚至对一般原则有什么建议？