MKPolyline – > NSKeyedArchiver – > NSData SIGABRT

在我的应用程序中,我试图将一组MKPolylines存储到NSUserDefaults

 NSData *data = [NSKeyedArchiver archivedDataWithRootObject:overlays]; [[NSUserDefaults standardUserDefaults] setObject:data forKey:@"theKey"]; 

得到:

 [MKPolyline encodeWithCoder:]: unrecognized selector sent to instance 0x169c20` Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '- [MKPolyline encodeWithCoder:]: unrecognized selector sent to instance 0x1c57e0' 

编辑:我取得了一些进展。 MKPolylineView符合NSCoding协议,因此我已将我的MKPolyline数组转换为MKPolyline数组。 问题是,当我想稍后将它们添加回地图时,我无法将它们转换回MKPolyline 。 知道怎么做吗?

在此代码崩溃:

 NSData* data = [[NSUserDefaults standardUserDefaults] objectForKey:@"theKey"]; NSArray* overlays = [NSKeyedUnarchiver unarchiveObjectWithData:data]; for(MKPolylineView* a in overlays) [mapView addOverlay:a.overlay]; 2011-10-17 21:15:56.416 Trail Tracker[4269:707] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[__NSArrayM insertObject:atIndex:]: object cannot be nil' *** First throw call stack: (0x34b2f8bf 0x36c3a1e5 0x34a8420f 0x35697595 0x6257 0x62db 0x365f77ff 0x36601d53 0x36601cc1 0x366a1339 0x366a014f 0x366fad97 0x649b 0x36671565 0x366e9ce7 0x31fcc943 0x34b03a63 0x34b036c9 0x34b0229f 0x34a854dd 0x34a853a5 0x351f9fed 0x365ec743 0x2c75 0x2c34) terminate called throwing an exception(gdb) 

我不太确定这一点,但MKPolylines是由CLLocationCoordinate2D数组构成的,它包含lat和long的浮点值。

因此,如果您可以将此CLLocationCoordinate2D数组转换为字典数组,我认为您可以将这些行保存在用户默认值中。

你可以做这样的事情

 MKMapPoint *points = overlays.points; NSMutableArray *temp = [NSMutableArray array]; for(int i = 0; i < points.length; i++) { // Not sure for this part NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithFloat:points[i].x], @"x", [NSNumber numberWithFloat:points[i].y], @"y", nil]; [temp addObject:dict]; } 

然后,您可以使用此数组将覆盖点存储在nsuserdefaults中,如下所示

 NSData *data = [NSKeyedArchiver archivedDataWithRootObject:temp]; [[NSUserDefaults standardUserDefaults] setObject:data forKey:@"theKey"]; 

从查看inheritance层次结构NSObject – > MKShape – > MKMultiPoint – > MKPolyline,它们都不符合NSCoding协议。 因此,您可以考虑inheritanceMKPolyline并包含NSCoding协议并实现所需的方法并使用它。