Question

I try to find object in my array and if success I need to replace object from my array to new object

 for (id existingSig in allSignature)
   if ([[existingSig objectForKey:@"SignatureName"] isEqualToString:[item objectForKey:@"name"]])
    {    
      [allSignature removeObject:existingSig];
      [allSignature addObject:[NSDictionary dictionaryWithObjectsAndKeys:@"1", @"SignatureIsRich", [item objectForKey:@"name"], @"SignatureName", generatedID, @"SignatureUniqueId", nil]];
     }

I have error ‘NSCFArray: 0x100551f10> was mutated while being enumerated’

Answer 1

As others have said, you cannot mutate a MutableArray while it is being Enumerated. You could handle it by having two arrays of what to remove and what to add after the loop.

NSMutableArray *remove = [NSMutableArray array];
NSMutableArray *add = [NSMutableArray array];
for (id existingSig in allSignature){
   if ([[existingSig objectForKey:@"SignatureName"] isEqualToString:[item objectForKey:@"name"]])
    {    
      // Add to the array of objects to be removed
      [remove addObject:existingSig];
      // Add to the array of objects to be added
      [add addObject:[NSDictionary dictionaryWithObjectsAndKeys:@"1", @"SignatureIsRich", [item objectForKey:@"name"], @"SignatureName", generatedID, @"SignatureUniqueId", nil]];
     }
}
[allSignature removeObjectsInArray:remove]; // Remove objects
[allSignature addObjectsFromArray:add]; // Add new objects