gistfile1.txt

marcas.h
@interface marcas : NSObject<NSCoding> {
    NSString *marca;
    NSString *idMarca;
}

@property(nonatomic, retain) NSString *marca;
@property(nonatomic, retain) NSString *idMarca;

@end


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marcas.m

- (id)initWithCoder:(NSCoder *)decoder {
    if (self = [super init]) {
        self.marca = [decoder decodeObjectForKey:@"marca"];
        self.idMarca = [decoder decodeObjectForKey:@"idMarca"];
    }
    return self;
}

- (void)encodeWithCoder:(NSCoder *)encoder {
    [encoder encodeObject:marca forKey:@"marca"];
    [encoder encodeObject:idMarca forKey:@"idMarca"];
}
@end