在NSUserDefaults中將自定義對象存儲在NSMutableArray中

我最近一直試圖將我的iPhone應用程序的搜索結果存儲在NSUserDefaults集合中。我也使用它來成功保存用戶註冊信息，但由於某種原因，試圖存儲自定義位置類的NSMutableArray始終爲空。在NSUserDefaults中將自定義對象存儲在NSMutableArray中

我試圖轉換的NSMutableArray到NSData的元素作爲這個帖子的，但我得到了相同的結果（Possible to save an integer array using NSUserDefaults on iPhone?）

我已經嘗試了代碼示例：

節省：

[prefs setObject:results forKey:@"lastResults"]; 
[prefs synchronize];

或

NSData *data = [NSData dataWithBytes:&results length:sizeof(results)]; 
[prefs setObject:data forKey:@"lastResults"];

或

NSData *data = [NSKeyedArchiver archivedDataWithRootObject:results]; 
[prefs setObject:data forKey:@"lastResults"];

負載：

lastResults = (NSMutableArray *)[prefs objectForKey:@"lastResults"];

或

NSData *data = [prefs objectForKey:@"lastResults"]; 
memcpy(&lastResults, data.bytes, data.length);

或

NSData *data = [prefs objectForKey:@"lastResults"]; 
lastResults = [NSKeyedUnarchiver unarchiveObjectWithData:data];

經過以下建議下面我也implemente d NSCoder在我對象（忽略的NSString其臨時的過度使用）：

#import "Location.h" 


@implementation Location 

@synthesize locationId; 
@synthesize companyName; 
@synthesize addressLine1; 
@synthesize addressLine2; 
@synthesize city; 
@synthesize postcode; 
@synthesize telephoneNumber; 
@synthesize description; 
@synthesize rating; 
@synthesize priceGuide; 
@synthesize latitude; 
@synthesize longitude; 
@synthesize userLatitude; 
@synthesize userLongitude; 
@synthesize searchType; 
@synthesize searchId; 
@synthesize distance; 
@synthesize applicationProviderId; 
@synthesize contentProviderId; 

- (id) initWithCoder: (NSCoder *)coder 
{ 
    if (self = [super init]) 
    { 
     self.locationId = [coder decodeObjectForKey:@"locationId"]; 
     self.companyName = [coder decodeObjectForKey:@"companyName"]; 
     self.addressLine1 = [coder decodeObjectForKey:@"addressLine1"]; 
     self.addressLine2 = [coder decodeObjectForKey:@"addressLine2"]; 
     self.city = [coder decodeObjectForKey:@"city"]; 
     self.postcode = [coder decodeObjectForKey:@"postcode"]; 
     self.telephoneNumber = [coder decodeObjectForKey:@"telephoneNumber"]; 
     self.description = [coder decodeObjectForKey:@"description"]; 
     self.rating = [coder decodeObjectForKey:@"rating"]; 
     self.priceGuide = [coder decodeObjectForKey:@"priceGuide"]; 
     self.latitude = [coder decodeObjectForKey:@"latitude"]; 
     self.longitude = [coder decodeObjectForKey:@"longitude"]; 
     self.userLatitude = [coder decodeObjectForKey:@"userLatitude"]; 
     self.userLongitude = [coder decodeObjectForKey:@"userLongitude"]; 
     self.searchType = [coder decodeObjectForKey:@"searchType"]; 
     self.searchId = [coder decodeObjectForKey:@"searchId"]; 
     self.distance = [coder decodeObjectForKey:@"distance"]; 
     self.applicationProviderId = [coder decodeObjectForKey:@"applicationProviderId"]; 
     self.contentProviderId = [coder decodeObjectForKey:@"contentProviderId"]; 
    } 
} 

- (void) encodeWithCoder: (NSCoder *)coder 
{ 
    [coder encodeObject:locationId forKey:@"locationId"]; 
    [coder encodeObject:companyName forKey:@"companyName"]; 
    [coder encodeObject:addressLine1 forKey:@"addressLine1"]; 
    [coder encodeObject:addressLine2 forKey:@"addressLine2"]; 
    [coder encodeObject:city forKey:@"city"]; 
    [coder encodeObject:postcode forKey:@"postcode"]; 
    [coder encodeObject:telephoneNumber forKey:@"telephoneNumber"]; 
    [coder encodeObject:description forKey:@"description"]; 
    [coder encodeObject:rating forKey:@"rating"]; 
    [coder encodeObject:priceGuide forKey:@"priceGuide"]; 
    [coder encodeObject:latitude forKey:@"latitude"]; 
    [coder encodeObject:longitude forKey:@"longitude"]; 
    [coder encodeObject:userLatitude forKey:@"userLatitude"]; 
    [coder encodeObject:userLongitude forKey:@"userLongitude"]; 
    [coder encodeObject:searchType forKey:@"searchType"]; 
    [coder encodeObject:searchId forKey:@"searchId"]; 
    [coder encodeObject:distance forKey:@"distance"]; 
    [coder encodeObject:applicationProviderId forKey:@"applicationProviderId"]; 
    [coder encodeObject:contentProviderId forKey:@"contentProviderId"]; 

}

來源

2009-02-11 Anthony Main

176

對於陣列中加載自定義對象，這是我用搶的數組：

NSUserDefaults *currentDefaults = [NSUserDefaults standardUserDefaults]; 
NSData *dataRepresentingSavedArray = [currentDefaults objectForKey:@"savedArray"]; 
if (dataRepresentingSavedArray != nil) 
{ 
    NSArray *oldSavedArray = [NSKeyedUnarchiver unarchiveObjectWithData:dataRepresentingSavedArray]; 
    if (oldSavedArray != nil) 
     objectArray = [[NSMutableArray alloc] initWithArray:oldSavedArray]; 
    else 
     objectArray = [[NSMutableArray alloc] init]; 
}

您應該檢查從用戶默認返回的數據不爲零，因爲我相信解除封存從零導致崩潰。

存檔很簡單，使用下面的代碼：

[[NSUserDefaults standardUserDefaults] setObject:[NSKeyedArchiver archivedDataWithRootObject:objectArray] forKey:@"savedArray"];

由於f3lix指出的那樣，你需要使你的自定義對象均符合歐盟的NSCoding協議。像下面添加方法應該做的伎倆：

- (void)encodeWithCoder:(NSCoder *)coder; 
{ 
    [coder encodeObject:label forKey:@"label"]; 
    [coder encodeInteger:numberID forKey:@"numberID"]; 
} 

- (id)initWithCoder:(NSCoder *)coder; 
{ 
    self = [super init]; 
    if (self != nil) 
    { 
     label = [[coder decodeObjectForKey:@"label"] retain]; 
     numberID = [[coder decodeIntegerForKey:@"numberID"] retain]; 
    } 
    return self; 
}

來源

2009-02-11 17:20:35

我已經將你的代碼和實現NSCoder的對象複製到原型中，但是desp ite來自UserDefaults的NSData有數據，最終數組仍然有0的計數。任何想法？我會嘗試將我的原型上傳到某處 – 2009-02-13 16:31:50

請參閱「NSUserDefaults的爲什麼沒能挽救的NSMutableDictionary在iPhone SDK？「（Why NSUserDefaults failed to save NSMutableDictionary in iPhone SDK?）

如果你想（反）序列化的自定義對象，你必須提供的功能（反）序列化的數據（NSCoding協議）。該解決方案你是指與INT作品數組，因爲數組是不是對象，而是一個連續的內存塊。

來源

2009-02-11 14:43:21 f3lix

我認爲您的權利，我會看看到NSCoding（除非你有一個建議linky），本身是由上NSString的對象是所有的，所以我想我可以寫我自己的串行器，並把它們全部放入一個字符串數組 – 2009-02-11 14:56:07

好吧，所以我已經實現了NSCode，但仍然沒有使用NSArchiver – 2009-02-11 16:29:53

我認爲它看起來像你的代碼不保存結果陣列的問題。它的加載數據嘗試使用

lastResults = [prefs arrayForKey:@"lastResults"];

這將返回數組s通過鑰匙特化。

來源

2009-02-11 14:49:02 Gcoop

我會建議不要試圖在默認數據庫中存儲這樣的東西。

SQLite很容易拾取和使用。我在我的一個屏幕錄像（http://pragprog.com/screencasts/v-bdiphone）中插入了一段關於我寫的簡單包裝（您可以在不購買SC的情況下獲得代碼）。

在應用程序空間中存儲應用程序數據要乾淨得多。

所有這一切說，如果它仍然是有道理的把這個數據放入默認的數據庫，然後看到帖子f3lix張貼。

來源

2009-02-11 14:51:50

謝謝你的建議，但我真的不想開始編寫SQL查詢我在你的例子中看到）只是爲了一個有幾個字符串的對象 – 2009-02-11 16:58:39

我想你已經在你的initWithCoder方法得到一個錯誤，至少在所提供的代碼，你不回的「自我」的對象。

- (id) initWithCoder: (NSCoder *)coder 
{ 
    if (self = [super init]) 
    { 
     self.locationId = [coder decodeObjectForKey:@"locationId"]; 
     self.companyName = [coder decodeObjectForKey:@"companyName"]; 
     self.addressLine1 = [coder decodeObjectForKey:@"addressLine1"]; 
     self.addressLine2 = [coder decodeObjectForKey:@"addressLine2"]; 
     self.city = [coder decodeObjectForKey:@"city"]; 
     self.postcode = [coder decodeObjectForKey:@"postcode"]; 
     self.telephoneNumber = [coder decodeObjectForKey:@"telephoneNumber"]; 
     self.description = [coder decodeObjectForKey:@"description"]; 
     self.rating = [coder decodeObjectForKey:@"rating"]; 
     self.priceGuide = [coder decodeObjectForKey:@"priceGuide"]; 
     self.latitude = [coder decodeObjectForKey:@"latitude"]; 
     self.longitude = [coder decodeObjectForKey:@"longitude"]; 
     self.userLatitude = [coder decodeObjectForKey:@"userLatitude"]; 
     self.userLongitude = [coder decodeObjectForKey:@"userLongitude"]; 
     self.searchType = [coder decodeObjectForKey:@"searchType"]; 
     self.searchId = [coder decodeObjectForKey:@"searchId"]; 
     self.distance = [coder decodeObjectForKey:@"distance"]; 
     self.applicationProviderId = [coder decodeObjectForKey:@"applicationProviderId"]; 
     self.contentProviderId = [coder decodeObjectForKey:@"contentProviderId"]; 
    } 

    return self; // this is missing in the example above 


}

我用

NSData *data = [NSKeyedArchiver archivedDataWithRootObject:results]; 
[prefs setObject:data forKey:@"lastResults"];

和

NSUserDefaults *currentDefaults = [NSUserDefaults standardUserDefaults]; 
NSData *dataRepresentingSavedArray = [currentDefaults objectForKey:@"lastResults"]; 
if (dataRepresentingSavedArray != nil) 
{ 
     NSArray *oldSavedArray = [NSKeyedUnarchiver unarchiveObjectWithData:dataRepresentingSavedArray]; 
     if (oldSavedArray != nil) 
       objectArray = [[NSMutableArray alloc] initWithArray:oldSavedArray]; 
     else 
       objectArray = [[NSMutableArray alloc] init]; 
}

和它的工作非常適合我。

與問候，

斯特凡

來源

2009-04-15 13:43:24

在NSUserDefaults中將自定義對象存儲在NSMutableArray中

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