How to remove an object from NSFetchRequest sortDescriptors NSArray

Question

i want to traverse through sortDescriptors NSArray and remove an object that doesn't meet a certain criteria. Can someone here please show me how can i do this correctly.

NSFetchRequest* request = [NSFetchRequest fetchRequestWithEntityName:@“CarsInventory”];
request.sortDescriptors = [NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@“model” ascending:YES selector:@selector(localizedCaseInsensitiveCompare:)]];

for (CarsInventory* carInfo in request.sortDescriptors)
{
        if (![self isCarWithin5FileRadius:carInfo.location])
        {
            [request.sortDescriptors delete: bookInfo]; // CRASH         
        }
}

Answer 1

I believe you have two problems here:

• NSArray is not mutable, hence you cannot remove items from it. You should convert it to NSMutableArray .
• you should not remove items from an array during enumeration. You can iterate through the array using for(int i=0;i<[yourArray count];i++) , however.

Answer 2

try this code

NSFetchRequest* request = [NSFetchRequest fetchRequestWithEntityName:@“CarsInventory”];
NSArray *sortedArray = [NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@“model” ascending:YES selector:@selector(localizedCaseInsensitiveCompare:)]];

NSMutableArray *mutArray=[NSMutableArray arrayWithCapacity:[sortedArray count]];

for (CarsInventory* carInfo in sortedArray)
{
    if ([self isCarWithin5FileRadius:carInfo.location])
    {
        [mutArray addObject:carInfo];// add it to mutable array
    }

}

NSLog(@"New Mut Array--%@",mutArray); //log the final list