iOS runtime 자동 아카이빙 문제

이상 정보

[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[0]'

두 번째 문제의 원인

2.1 코드 블록

/**
 *   
 */
- (void)encodeWithCoder:(NSCoder *)encoder
{
	unsigned int count = 0;
	Ivar *ivars = class_copyIvarList([GMAccessToken class], &count);
	
	for (int i = 0; i<count; i++) {
		//  i 
		Ivar ivar = ivars[i];
		
		//  
		const char *name = ivar_getName(ivar);
		
		//  
		NSString *key = [NSString stringWithUTF8String:name];
		id value = [self valueForKey:key];
		[encoder encodeObject:value forKey:key];
	}
	
	free(ivars);
}

/**
 *   
 */
- (id)initWithCoder:(NSCoder *)decoder
{
	
	if (self = [super init]) {
		unsigned int count = 0;
		Ivar *ivars = class_copyIvarList([GMAccessToken class], &count);
		
		for (int i = 0; i<count; i++) {
			//  i 
			Ivar ivar = ivars[i];
			
			//  
			//  name  ， ， 
			const char *name = ivar_getName(ivar);
			
			//  
			NSString *key = [NSString stringWithUTF8String:name];
//			NSString *key = [[NSString stringWithUTF8String:name] substringFromIndex:1];
			id value = [decoder decodeObjectForKey:key];
			GMLog(@"%@====%@",key,value);
			
			//  
			[self setValue:value forKey:key];
		}
		
		free(ivars);
	}
	return self;
}

2.2 출력

GMLog(@"%@====%@",key,value); 
2016-03-30 22:45:40.058 RT[26053:2065800] _access_token====(null)
2016-03-30 22:45:40.059 RT[26053:2065800] _expires_in====(null)
2016-03-30 22:45:40.059 RT[26053:2065800] _expires_time====(null)
2016-03-30 22:45:40.059 RT[26053:2065800] _remind_in====(null)
2016-03-30 22:45:40.059 RT[26053:2065800] _uid====(null)

NSString *key = [NSString stringWithUTF8String:name];

세 가지 해결 방법

NSString *key = [[NSString stringWithUTF8String:name] substringFromIndex:1];