Correct way to check null values

Question

What is the correct way to check if attribute with type Integer is not null in the new sdk 10.1.

self.capacityStepper.value = [self.feature attributreAsIntForKey:@Capacity exist:Bool]

I don''t know what to put for value for "exist". Setting it to YES is giving me warning as "Incompatible Integer to Pointer". I need above value assignment to happen only when attribute value is not null;

DiveshGoyal · Accepted Answer

BOOL exists;
int temp = [self.feature attributreAsIntForKey:@Capacity exist:&exists]
if(exists){
  self.capacityStepper.value = temp;
}