保存自定义Objective-c对象的层次结构以实现持久性的最佳方法

Question

我正在编写一个应用程序，该应用程序允许用户为可能选择的到达不同位置的多条路线计时，然后将其保存为可查看数据的存档。 我遇到的问题是保存数据以供永久使用。 我已经阅读了NSCoding协议，但是由于对象中存在不兼容的属性（例如CLCoordinateLocation2D），它似乎无法满足我的对象需求（我知道我可以分解成更多的组件，例如纬度和经度，但是我认为必须有更好的方法），但还有其他方法。 我来自Java，我需要做的就是实现可序列化的接口，我很高兴，但是我对Objective-C还是陌生的，并且不确定解决问题的最佳方法。

这是我需要序列化的对象结构。

@interface BestRouteBrain : NSObject < CLLocationManagerDelegate, NSCoding > {
    NSDictionary *segments;
    BestRouteTimer *timer;
    BestRouteSegment *currentSegment;
    //Manages attributes that communicate with GPS
    CLLocationManager *locationManager;
    Firebase *firebase;
   //NSDictionary *routesByTimeOfDay;
   //NSDictionary *routesByAverage;
}

@property ( strong ) CLLocationManager *locationManager;
@property BestRouteSegment *currentSegment;
@property BestRouteTimer *timer;
@property NSDictionary *segments;
@property Firebase *firebase;

基本上，我需要序列化的就是NSDictionary *segments 。 这是段的样子

@interface BestRouteSegment :NSObject <NSCoding>{
    // Name of segment
    NSString *segmentName;
    // String reprsenting starting location for segment
    NSString *startingLocation;
    // String representing ending location for segment
    NSString *endingLocation;
    //Key is name of route and value is a route object;
    NSDictionary *routesForSegment;
    CLLocationCoordinate2D startCoord;
    CLLocationCoordinate2D endCoord;
}

@property CLLocationCoordinate2D startCoord;
@property CLLocationCoordinate2D endCoord;
@property NSString *startingLocation;
@property NSString *endingLocation;
@property NSString *segmentName;
@property NSDictionary *routesForSegment;

该对象中的所有属性也都需要序列化，包括NSDictionary *routesForSegment 。 这是一条路线的样子，

@interface Route : NSObject {
    // Name of route given by user
    NSString *routeName;
    // The total average time for all trips using this route
    double  avgRouteTime;
    // Array of trips which used this route
    NSArray *allTripsFromRoute;
}

@property NSString *routeName;
@property double avgRouteTime;
@property NSArray *allTripsFromRoute;

所有这些属性也需要序列化。 最后，这是一次旅行的样子。

@interface BestRouteTrip : NSObject {
    // Time elapsed for current trip
    double tripTime;
    // String representing time of day - Departure time is
    NSString *timeOfDay;
    NSDate *morningBeforeTrafic;// from 12:00am to 6:30am
    NSDate *morningTrafic; // from 6:30am to 9:30am
    NSDate *morningAfterTrafic; // from 9:30am to 12:00pm
    NSDate *afternoon;    // from 12:00pm to 3:30pm
    NSDate *eveningTrafic; // from 3:30pm to 6:30pm
    NSDate *eveningAfterTrafic; // from 6:30pm to 12:00p
}

@property double tripTime;
@property NSString *timeOfDay;
@property NSDate *morningBeforeTrafic;// from 12:00am to 6:30am
@property NSDate *morningTrafic; // from 6:30am to 9:30am
@property NSDate *morningAfterTrafic; // from 9:30am to 12:00pm
@property NSDate *afternoon;    // from 12:00pm to 3:30pm
@property NSDate *eveningTrafic; // from 3:30pm to 6:30pm
@property NSDate *eveningAfterTrafic; // from 6:30pm to 12:00p

我在这里需要序列化的仅有两个值是double tripTime和NSString *timeOfDay 。

摘要：大脑具有需要序列化的片段字典。 该段具有要序列化的属性，包括路由字典（另一个自定义对象）。 Routes具有要序列化的属性，包括Trips数组。 最后，行程有两个需要序列化的值。

在此先感谢您的协助。

Answer 1

好的，所以我通过在BestRouteSegment内实现NSCoding协议解决了这个问题，该协议对我的段进行了编码而没有错误。 这是遵守上述协议的方法。

- (void)encodeWithCoder:(NSCoder *)encoder {
    NSLog(@"Encode in segment was called");
    [ encoder encodeDouble:self.startCoord.latitude
                    forKey:@"startCoord.latitude" ];
    [ encoder encodeDouble:self.startCoord.longitude
                    forKey:@"startCoord.longitude" ];
    [ encoder encodeDouble:self.endCoord.latitude
                    forKey:@"endCoord.latitude" ];
    [ encoder encodeDouble:self.endCoord.longitude 
                    forKey:@"endCoord.longitude" ];
    [ encoder encodeObject:self.segmentName
                    forKey:@"segmentName" ];
    [ encoder encodeObject:self.startingLocation
                    forKey:@"startingLocation" ];
    [ encoder encodeObject:self.endingLocation
                    forKey:@"endingLocation" ];
    [ encoder encodeObject:self.routesForSegment
                    forKey:@"routesForSegment" ];
}

- (id)initWithCoder:(NSCoder *)adecoder {
    NSLog(@"Init with coder was called in segment");
    if ( self = [ super init ] ) {
        self.startCoord =
        CLLocationCoordinate2DMake(
                                   [ adecoder decodeDoubleForKey:@"startCoord.lattitude" ],
                                   [ adecoder decodeDoubleForKey:@"startCoord.longitude" ]
                                   );
        self.endCoord =
        CLLocationCoordinate2DMake(
                                   [ adecoder decodeDoubleForKey:@"endCoord.lattitude" ],
                                   [ adecoder decodeDoubleForKey:@"endCoord.longitude" ]
                                   );
        self.segmentName =
        [ adecoder decodeObjectForKey:@"segmentName" ];
        self.startingLocation =
        [ adecoder decodeObjectForKey:@"startingLocation" ];
        self.endingLocation =
        [ adecoder decodeObjectForKey:@"endingLocation" ];
        self.routesForSegment =
        [ adecoder decodeObjectForKey:@"routesForSegment" ];

    }
    return self;
}