How to save non property values in iOS using NSUserDefaults? - iphone

Question

I am saving the AccessToken that I got from one Social Networking website.when I save this then I come to know that We can't directly save the non property values in iOS SDK.
Then from tutorial I came to know that I should implement the NSCoding class. Then I did this.
NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:self.accessToken];
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:myEncodedObject forKey:#"myEncodedObjectKey"];
[defaults synchronize];
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSData *myEncodedObject = [defaults objectForKey:#"myEncodedObjectKey"];
LOAToken *obj = (LOAToken *)[NSKeyedUnarchiver unarchiveObjectWithData: myEncodedObject];
I implemented the NSCoding delegate but I don't know how to implement the delegate methods. Then when I run this code I get the error
`"-[LOAToken encodeWithCoder:]: unrecognized selector sent to instance 0xa2bb970"
I am unable to implement the NSCoding along with my code. Any Suggestions? Also Is there any other way to store the non-property values like AccessToken for further use.
Edit:
I am getting this access token of LinkedIn and want to store like this:
self.accessToken = [[LOAToken alloc] initWithHTTPResponseBody:responseBody];
// The accessToken Printed....Here I have the AccessToken Value.
NSLog(#"Access===%#",self.accessToken);
NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:self.accessToken];
NSLog(#"myEncodedObject===%#",myEncodedObject);
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:myEncodedObject forKey:#"myEncodedObjectKey"];
[defaults synchronize];
This was getting crashed since I have not used NSCoding implementation which I did in LOAToken class which you suggested.
I made one variable value in LAToken class and implemented these two methods.
-(void)encodeWithCoder:(NSCoder *)encoder
{
[encoder encodeObject:value forKey:#"Value"];
}
-(id)initWithCoder:(NSCoder *)decoder
{
self.value = [decoder decodeObjectForKey:#"Value"];
return self;
}
Then while retrieving I am using this.
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSData *myEncodedObject = [defaults objectForKey:#"myEncodedObjectKey"];
LOAToken *obj = (OAToken *)[NSKeyedUnarchiver unarchiveObjectWithData: myEncodedObject];
When I Printed the data both at the time of archiving and Unarchiving then the data printed is same.This may be due to two reasons.
The data which I have unarchived is right and the way of retrieving is wrong which you can suggest through my code above.
The data which I am saving at the time of Archiving is null.So the null is saved.
Is there any limitation in saving the Access Token.May be this can be a reason for null output.
The output which I got is this:
oauth_token "(null)" oauth_token_secret "(null)" oauth_verifier "(null)"
The text "oauth_token" "oauth_token_secret" "oauth_verifier" is coming from AccessToken but their values are null.
Edit 2: This is OAToken Class of LinkedIn where I am getting the Access Token.The same token I am passing in encoding method
OAToken.h
#import <Foundation/Foundation.h>
#interface OAToken : NSObject {
#protected
NSString *key;
NSString *secret;
NSString *session;
NSString *verifier;
NSNumber *duration;
NSMutableDictionary *attributes;
NSDate *created;
BOOL renewable;
BOOL forRenewal;
OAToken *value;
}
#property(retain, readwrite) NSString *key;
#property(retain, readwrite) NSString *secret;
#property(retain, readwrite) NSString *session;
#property(retain, readwrite) NSString *verifier;
#property(retain, readwrite) NSNumber *duration;
#property(retain, readwrite) NSMutableDictionary *attributes;
#property(readwrite, getter=isForRenewal) BOOL forRenewal;
#property (nonatomic,retain) OAToken *value;
- (id)initWithKey:(NSString *)aKey secret:(NSString *)aSecret;
- (id)initWithKey:(NSString *)aKey
secret:(NSString *)aSecret
session:(NSString *)aSession
verifier:(NSString *)aVerifier
duration:(NSNumber *)aDuration
attributes:(NSMutableDictionary *)theAttributes
created:(NSDate *)creation
renewable:(BOOL)renew;
- (id)initWithHTTPResponseBody:(NSString *)body;
- (id)initWithUserDefaultsUsingServiceProviderName:(NSString *)provider prefix:(NSString *)prefix;
- (int)storeInUserDefaultsWithServiceProviderName:(NSString *)provider prefix:(NSString *)prefix;
- (BOOL)isValid;
- (void)setAttribute:(NSString *)aKey value:(NSString *)aValue;
- (NSString *)attribute:(NSString *)aKey;
- (void)setAttributesWithString:(NSString *)aAttributes;
- (NSString *)attributeString;
- (BOOL)hasExpired;
- (BOOL)isRenewable;
- (void)setDurationWithString:(NSString *)aDuration;
- (void)setVerifierWithUrl:(NSURL *)aURL;
- (BOOL)hasAttributes;
- (NSMutableDictionary *)parameters;
- (BOOL)isEqualToToken:(OAToken *)aToken;
+ (void)removeFromUserDefaultsWithServiceProviderName:(const NSString *)provider prefix:(const NSString *)prefix;
#end
OAToken.m
#import "NSString+URLEncoding.h"
#import "OAToken.h"
#interface OAToken (Private)
+ (NSString *)settingsKey:(const NSString *)name provider:(const NSString *)provider prefix:(const NSString *)prefix;
+ (id)loadSetting:(const NSString *)name provider:(const NSString *)provider prefix:(const NSString *)prefix;
+ (void)saveSetting:(NSString *)name object:(id)object provider:(const NSString *)provider prefix:(const NSString *)prefix;
+ (NSNumber *)durationWithString:(NSString *)aDuration;
+ (NSMutableDictionary *)attributesWithString:(NSString *)theAttributes;
#end
#implementation OAToken
#synthesize key, secret, session, verifier, duration, attributes, forRenewal;
#synthesize value;
#pragma mark Encode
-(void)encodeWithCoder:(NSCoder *)encoder
{
// This prints the value....
NSLog(#"value===%#",self.value);
[encoder encodeObject:self.value forKey:#"Value"];
}
-(id)initWithCoder:(NSCoder *)decoder
{
OAToken *hell= [decoder decodeObjectForKey:#"Value"];
// This don't have the value.It is null.
NSLog(#"hell===%#",hell);
return self;
}
#pragma mark init
- (id)init {
return [self initWithKey:nil secret:nil];
}
- (id)initWithKey:(NSString *)aKey secret:(NSString *)aSecret {
return [self initWithKey:aKey secret:aSecret session:nil verifier:nil duration:nil
attributes:nil created:nil renewable:NO];
}
- (id)initWithKey:(NSString *)aKey
secret:(NSString *)aSecret
session:(NSString *)aSession
verifier:(NSString *)aVerifier
duration:(NSNumber *)aDuration
attributes:(NSMutableDictionary *)theAttributes
created:(NSDate *)creation
renewable:(BOOL)renew
{
[super init];
self.key = aKey;
self.secret = aSecret;
self.session = aSession;
self.verifier = aVerifier;
self.duration = aDuration;
self.attributes = theAttributes;
created = [creation retain];
renewable = renew;
forRenewal = NO;
return self;
}
- (void)setVerifierWithUrl:(NSURL *)aURL
{
NSString *query = [aURL query];
NSArray *pairs = [query componentsSeparatedByString:#"&"];
for (NSString *pair in pairs)
{
NSArray *elements = [pair componentsSeparatedByString:#"="];
if ([[elements objectAtIndex:0] isEqualToString:#"oauth_verifier"])
{
self.verifier = [elements objectAtIndex:1];
}
}
}
- (id)initWithHTTPResponseBody:(const NSString *)body
{
NSString *aKey = nil;
NSString *aSecret = nil;
NSString *aSession = nil;
NSString *aVerifier = nil;
NSNumber *aDuration = nil;
NSDate *creationDate = nil;
NSMutableDictionary *attrs = nil;
BOOL renew = NO;
NSArray *pairs = [body componentsSeparatedByString:#"&"];
for (NSString *pair in pairs)
{
NSArray *elements = [pair componentsSeparatedByString:#"="];
if ([[elements objectAtIndex:0] isEqualToString:#"oauth_token"])
{
aKey = [elements objectAtIndex:1];
}
else if ([[elements objectAtIndex:0] isEqualToString:#"oauth_token_secret"])
{
aSecret = [elements objectAtIndex:1];
}
else if ([[elements objectAtIndex:0] isEqualToString:#"oauth_verifier"])
{
aVerifier = [elements objectAtIndex:1];
}
else if ([[elements objectAtIndex:0] isEqualToString:#"oauth_session_handle"])
{
aSession = [elements objectAtIndex:1];
}
else if ([[elements objectAtIndex:0] isEqualToString:#"oauth_token_duration"])
{
aDuration = [[self class] durationWithString:[elements objectAtIndex:1]];
creationDate = [NSDate date];
}
else if ([[elements objectAtIndex:0] isEqualToString:#"oauth_token_attributes"])
{
attrs = [[self class] attributesWithString:[[elements objectAtIndex:1] decodedURLString]];
}
else if ([[elements objectAtIndex:0] isEqualToString:#"oauth_token_renewable"])
{
NSString *lowerCase = [[elements objectAtIndex:1] lowercaseString];
if ([lowerCase isEqualToString:#"true"] || [lowerCase isEqualToString:#"t"]) {
renew = YES;
}
}
}
value=[self initWithKey:aKey
secret:aSecret
session:aSession
verifier:aVerifier
duration:aDuration
attributes:attrs
created:creationDate
renewable:renew];
return [self initWithKey:aKey
secret:aSecret
session:aSession
verifier:aVerifier
duration:aDuration
attributes:attrs
created:creationDate
renewable:renew];
}
- (id)initWithUserDefaultsUsingServiceProviderName:(const NSString *)provider prefix:(const NSString *)prefix {
[super init];
self.key = [OAToken loadSetting:#"key" provider:provider prefix:prefix];
self.secret = [OAToken loadSetting:#"secret" provider:provider prefix:prefix];
self.session = [OAToken loadSetting:#"session" provider:provider prefix:prefix];
self.verifier = [OAToken loadSetting:#"verifier" provider:provider prefix:prefix];
self.duration = [OAToken loadSetting:#"duration" provider:provider prefix:prefix];
self.attributes = [OAToken loadSetting:#"attributes" provider:provider prefix:prefix];
created = [OAToken loadSetting:#"created" provider:provider prefix:prefix];
renewable = [[OAToken loadSetting:#"renewable" provider:provider prefix:prefix] boolValue];
if (![self isValid]) {
[self autorelease];
return nil;
}
return self;
}
#pragma mark dealloc
- (void)dealloc {
self.key = nil;
self.secret = nil;
self.duration = nil;
self.attributes = nil;
[super dealloc];
}
#pragma mark settings
- (BOOL)isValid {
return (key != nil && ![key isEqualToString:#""] && secret != nil && ![secret isEqualToString:#""]);
}
- (int)storeInUserDefaultsWithServiceProviderName:(const NSString *)provider prefix:(const NSString *)prefix {
[OAToken saveSetting:#"key" object:key provider:provider prefix:prefix];
[OAToken saveSetting:#"secret" object:secret provider:provider prefix:prefix];
[OAToken saveSetting:#"created" object:created provider:provider prefix:prefix];
[OAToken saveSetting:#"duration" object:duration provider:provider prefix:prefix];
[OAToken saveSetting:#"session" object:session provider:provider prefix:prefix];
[OAToken saveSetting:#"verifier" object:verifier provider:provider prefix:prefix];
[OAToken saveSetting:#"attributes" object:attributes provider:provider prefix:prefix];
[OAToken saveSetting:#"renewable" object:renewable ? #"t" : #"f" provider:provider prefix:prefix];
[[NSUserDefaults standardUserDefaults] synchronize];
return(0);
}
#pragma mark duration
- (void)setDurationWithString:(NSString *)aDuration {
self.duration = [[self class] durationWithString:aDuration];
}
- (BOOL)hasExpired
{
return created && [created timeIntervalSinceNow] > [duration intValue];
}
- (BOOL)isRenewable
{
return session && renewable && created && [created timeIntervalSinceNow] < (2 * [duration intValue]);
}
#pragma mark attributes
- (void)setAttribute:(const NSString *)aKey value:(const NSString *)aAttribute {
if (!attributes) {
attributes = [[NSMutableDictionary alloc] init];
}
[attributes setObject: aAttribute forKey: aKey];
}
- (void)setAttributes:(NSMutableDictionary *)theAttributes {
[attributes release];
if (theAttributes) {
attributes = [[NSMutableDictionary alloc] initWithDictionary:theAttributes];
}else {
attributes = nil;
}
}
- (BOOL)hasAttributes {
return (attributes && [attributes count] > 0);
}
- (NSString *)attributeString {
if (![self hasAttributes]) {
return #"";
}
NSMutableArray *chunks = [[NSMutableArray alloc] init];
for(NSString *aKey in self->attributes) {
[chunks addObject:[NSString stringWithFormat:#"%#:%#", aKey, [attributes objectForKey:aKey]]];
}
NSString *attrs = [chunks componentsJoinedByString:#";"];
[chunks release];
return attrs;
}
- (NSString *)attribute:(NSString *)aKey
{
return [attributes objectForKey:aKey];
}
- (void)setAttributesWithString:(NSString *)theAttributes
{
self.attributes = [[self class] attributesWithString:theAttributes];
}
- (NSMutableDictionary *)parameters
{
NSMutableDictionary *params = [[[NSMutableDictionary alloc] init] autorelease];
if (key)
{
[params setObject:key forKey:#"oauth_token"];
if ([self isForRenewal])
{
[params setObject:session forKey:#"oauth_session_handle"];
}
}
else
{
if (duration)
{
[params setObject:[duration stringValue] forKey: #"oauth_token_duration"];
}
if ([attributes count])
{
[params setObject:[self attributeString] forKey:#"oauth_token_attributes"];
}
}
if (verifier)
{
[params setObject:verifier forKey:#"oauth_verifier"];
}
return params;
}
#pragma mark comparisions
- (BOOL)isEqual:(id)object {
if([object isKindOfClass:[self class]]) {
return [self isEqualToToken:(OAToken *)object];
}
return NO;
}
- (BOOL)isEqualToToken:(OAToken *)aToken {
/* Since ScalableOAuth determines that the token may be
renewed using the same key and secret, we must also
check the creation date */
if ([self.key isEqualToString:aToken.key] &&
[self.secret isEqualToString:aToken.secret]) {
/* May be nil */
if (created == aToken->created || [created isEqualToDate:aToken->created]) {
return YES;
}
}
return NO;
}
#pragma mark class_functions
+ (NSString *)settingsKey:(NSString *)name provider:(NSString *)provider prefix:(NSString *)prefix {
return [NSString stringWithFormat:#"OAUTH_%#_%#_%#", provider, prefix, [name uppercaseString]];
}
+ (id)loadSetting:(NSString *)name provider:(NSString *)provider prefix:(NSString *)prefix {
return [[NSUserDefaults standardUserDefaults] objectForKey:[self settingsKey:name
provider:provider
prefix:prefix]];
}
+ (void)saveSetting:(NSString *)name object:(id)object provider:(NSString *)provider prefix:(NSString *)prefix {
[[NSUserDefaults standardUserDefaults] setObject:object forKey:[self settingsKey:name
provider:provider
prefix:prefix]];
}
+ (void)removeFromUserDefaultsWithServiceProviderName:(NSString *)provider prefix:(NSString *)prefix {
NSArray *keys = [NSArray arrayWithObjects:#"key", #"secret", #"created", #"duration", #"session", #"verifier", #"attributes", #"renewable", nil];
for(NSString *name in keys) {
[[NSUserDefaults standardUserDefaults] removeObjectForKey:[OAToken settingsKey:name provider:provider prefix:prefix]];
}
}
+ (NSNumber *)durationWithString:(NSString *)aDuration {
NSUInteger length = [aDuration length];
unichar c = toupper([aDuration characterAtIndex:length - 1]);
int mult;
if (c >= '0' && c <= '9') {
return [NSNumber numberWithInt:[aDuration intValue]];
}
if (c == 'S') {
mult = 1;
} else if (c == 'H') {
mult = 60 * 60;
} else if (c == 'D') {
mult = 60 * 60 * 24;
} else if (c == 'W') {
mult = 60 * 60 * 24 * 7;
} else if (c == 'M') {
mult = 60 * 60 * 24 * 30;
} else if (c == 'Y') {
mult = 60 * 60 * 365;
} else {
mult = 1;
}
return [NSNumber numberWithInt: mult * [[aDuration substringToIndex:length - 1] intValue]];
}
+ (NSMutableDictionary *)attributesWithString:(NSString *)theAttributes {
NSArray *attrs = [theAttributes componentsSeparatedByString:#";"];
NSMutableDictionary *dct = [[NSMutableDictionary alloc] init];
for (NSString *pair in attrs) {
NSArray *elements = [pair componentsSeparatedByString:#":"];
[dct setObject:[elements objectAtIndex:1] forKey:[elements objectAtIndex:0]];
}
return [dct autorelease];
}
#pragma mark description
- (NSString *)description {
return [NSString stringWithFormat:#"oauth_token \"%#\" oauth_token_secret \"%#\" oauth_verifier \"%#\"", key, secret, verifier];
}
#end

Answer 1

You don't need any delegate methods. Instead, LOAToken should implement the initWithCoder: and encodeWithCoder: methods to actually save and restore the information that it contains. This is the meaning of implementing the NSCoding protocol.
You may want to have a read of the archiving docs here.
Once you have initially created your token from a web response or similar you should be using storeInUserDefaultsWithServiceProviderName: to store it into user defaults. Then, when you want to use it again call initWithUserDefaultsUsingServiceProviderName:. You don't need to do any encoding and decoding yourself.

Answer 2

To unarchive data
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSData *data = [defaults objectForKey:#"key"];
NSArray *arr = [NSKeyedUnarchiver unarchiveObjectWithData:data];
to archive data
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:array];
[defaults setValue:data forKey:#"key"];
[defaults synchronize];