i have got two different NSManagedObjectContexts both referring to the same NSPersistentStoreCoordinator, say context1 and context2.
I have an NSManag开发者_开发问答edObject out of context1. As I would like to edit it, not knowing whether it will be saved afterwards, I would like to get that object from context2. Context2 could be just trashed in the case that I do not want to save the NSManagedObject. In case of a save, I will merge context2 in context1.
But how do I get the object from context2? Is there an easy way to do this, or do I have to request the object with an predicate xyz=[NSManagedObject objectId]? And what does xyz have to be in that case?
You can specify the target NSManagedObjectContext, i.e.
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"MyEntity" inManagedObjectContext:managedObjectContext];
[request setEntity:entity];
myArray = [[managedObjectContext executeFetchRequest:request error:&error] mutableCopy];
Addition to your comment:
context2object = [myEntityArrayFromContext2 objectAtIndex:[myEntityArrayFromContext1 indexOfObject:context1object]];
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