XCode / iOS：NSCoding - 具有两个公共对象数组的对象图的持久性

@interface GraphNode {
    NSMutableArray *edges;
}

@implementation GraphNode

-(id)initWithCoder:(NSCoder *)coder {
    if (self = [super init]) {
        edges = [coder decodeObjectForKey:@"edges"];
    }
    return self;
}

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

@end

@interface GraphEdges {
  NSMutableArray *edges;
}

@implementation GraphEdges

-(id)initWithCoder:(NSCoder *)coder {
    if (self = [super init]) {
        edges = [coder decodeObjectForKey:@"edges"];
    }
    return self;
}

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

@end

edges

edges

edges

edges