ios - Save a NSArray to iCloud and retrieve it -

i have app saves nsmutablearray file in documents directory on ipad. saved

[residentdata writetofile:filepath atomically:no]; 

and read in by;

residentdata = [[nsmutablearray alloc] initwithcontentsoffile:filepath]; 

i need write file icloud, data needs available across several devices. have tried following create file in icloud;

nsdata *myfiledata = [nskeyedarchiver archiveddatawithrootobject:residentdata]; [filemanager createfileatpath:[icloudurl path] contents:myfiledata attributes:nil]; 

which indeed create file in correct place. struggling though understand how read file nsmutablearray (residentdata). have tried;

residentdata = [nskeyedunarchiver unarchiveobjectwithdata:myfiledata]; 

but doesn't decode array correctly. please can show me error of ways - suspect fundamental misunderstanding on part of nsdata blame, pointers welcome.

it clicked, approach wrong. don't need use of above. once have done the;

 [filemanager setubiquitous:yes itematurl:currentplace destinationurl:icloudurl error:&error]; 

the system takes care of else - i.e. accessing file with

residentdata = [[nsmutablearray alloc] initwithcontentsofurl:icloudurl]; 

has worked.