core data - How to insert NSManagedObject in other NSManagedObjectContext? -


i getting data server , converts them array of nsmanagedobject objects. array used display table.

how insert first element array peoples in persistent store?

- (void)viewdidload {      [self loaddata];      [self insertfirstpeople]; }  - (nsmanagedobjectcontext *)managedobjectcontext {     if(!_managedobjectcontext) _managedobjectcontext = [nsmanagedobjectcontext mr_context];     return _managedobjectcontext; }  - (void)loaddata {     ...         network request     ...     peoples = [nsmutablearray array];     (nsdictionary *item in items)     {         people *people = [podcast mr_createincontext:self.managedobjectcontext];         people.name = [item valueforkeypath:@"im:name.label"];         [peoples addobject:people];     } }  -(void)insertfirstpeople {     people *people = peoples[0];     nsmanagedobjectcontext *moc = [nsmanagedobjectcontext mr_defaultcontext];     [moc insertobject:people]     [moc mr_savetopersistentstoreandwait]; }

error:

an nsmanagedobject may in (or observed by) single nsmanagedobjectcontext.

i myself have found solution problem.

-(void)insertfirstpeople {     people *people = peoples[0];     coredatahelper *helper = [[coredatahelper alloc] init];     nsmanagerobjectcontext *context = [nsmanagedobjectcontext mr_defaultcontext];     [helper saveobject:people tocontext:context];     [context mr_saveonlyselfandwait]; }

coredatahelper.h

#import <foundation/foundation.h>   @interface coredatahelper : nsobject {     nsmutabledictionary* _lookup; } @property(nonatomic, retain) nsmutabledictionary *lookup;  -(void)savefrom:(nsmanagedobjectcontext *)current to:(nsmanagedobjectcontext *)parent;  - (nsmanagedobject *)saveobject:(nsmanagedobject *)object tocontext:(nsmanagedobjectcontext *)moc;  - (nsmanagedobject*)copyobject:(nsmanagedobject*)object                      tocontext:(nsmanagedobjectcontext*)moc                         parent:(nsstring*)parententity; @end

coredatahelper.m

#import "coredatahelper.h"  @implementation coredatahelper  @synthesize lookup = _lookup;  -(void)savefrom:(nsmanagedobjectcontext *)current to:(nsmanagedobjectcontext *)parent {     nsnotificationcenter *dnc = [nsnotificationcenter defaultcenter];           [dnc addobserverforname:nsmanagedobjectcontextdidsavenotification                            object:current queue:nil                        usingblock:^(nsnotification *notification)          {            [parent mergechangesfromcontextdidsavenotification:notification];          }];         nserror *error;         if (![current save:&error])           {               nslog(@"unresolved error %@, %@", error, [error userinfo]);           }            [dnc removeobserver:self                          name:nsmanagedobjectcontextdidsavenotification                        object:current]; }   - (nsmanagedobject *)saveobject:(nsmanagedobject *)object tocontext:(nsmanagedobjectcontext *)moc {     nsundomanager *docundomgr = [moc undomanager];     [docundomgr beginundogrouping];      nsmanagedobject *object2 = [self copyobject:object tocontext:moc parent:nil];      [moc processpendingchanges];     [docundomgr endundogrouping];     return object2; }  - (nsmanagedobject *)copyobject:(nsmanagedobject *)object                       tocontext:(nsmanagedobjectcontext *)moc                          parent:(nsstring *)parententity; {     nserror *error = nil;     nsstring *entityname = [[object entity] name];     nsmanagedobject *newobject = nil;     if ([moc objectregisteredforid:object.objectid])         newobject = [moc objectwithid:object.objectid];     else         newobject = [nsentitydescription                 insertnewobjectforentityforname:entityname                          inmanagedobjectcontext:moc];       if (![moc save:&error])     {         nslog(@"unresolved error %@, %@", error, [error userinfo]);     }      [[self lookup] setobject:newobject forkey:[object objectid]];      nsarray *attkeys = [[[object entity] attributesbyname] allkeys];     nsdictionary *attributes = [object dictionarywithvaluesforkeys:attkeys];      [newobject setvaluesforkeyswithdictionary:attributes];      id olddestobject = nil;     id temp = nil;     nsdictionary *relationships = [[object entity] relationshipsbyname];     (nsstring *key in [relationships allkeys]) {          nsrelationshipdescription *desc = [relationships valueforkey:key];         nsstring *destentityname = [[desc destinationentity] name];         if ([destentityname isequaltostring:parententity]) continue;          if ([desc istomany]) {              nsmutableset *newdestset = [nsmutableset set];              (olddestobject in [object valueforkey:key]) {                 temp = [[self lookup] objectforkey:[olddestobject objectid]];                 if (!temp) {                     temp = [self copyobject:olddestobject                                   tocontext:moc                                      parent:entityname];                 }                 [newdestset addobject:temp];             }              [newobject setvalue:newdestset forkey:key];          } else {             olddestobject = [object valueforkey:key];             if (!olddestobject) continue;              temp = [[self lookup] objectforkey:[olddestobject objectid]];             if (!temp && ![destentityname isequaltostring:parententity]) {                 temp = [self copyobject:olddestobject                               tocontext:moc                                  parent:entityname];             }              [newobject setvalue:temp forkey:key];         }     }      return newobject; }  @end

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