iOS Swift 3中的内存泄漏

Question

I have recently started Swift and learning Memory Management . And I am unable to solve this issue of memory leak.

This is my model class:

class Contact {

   var name: String?
   var age: String?

   weak var address: Address?

   deinit {
      print("Contact Delloacated")
   }

}

class Address {
   var address: String?
}

I am using this model in my controller.

class Controller: UIViewController {
  var contacts: [Contact]()?

 fetchContact() {
    let path = "some url"
    let url = URL(string: path)
    let session = URLSession.shared

    let task = session.dataTask(with: url!) { [weak self] (data, 
    response, error) in
     if error != nil {
            print(error!)
            return
        }
       if let data = data {
            do {
                let jsonResult = try JSONSerialization.jsonObject(with: 
                data, options: .mutableContainers)
                self?.contacts = [Contact]()

               let contact = Contact()

               // do some operation to get required data and append 
               //into contactList array

              self?.append?.append(contact)
  }

  override func viewDidLoad() {
    super.viewDidLoad()

    fetchContact()

    } 
}

Although I have used weak for Address in Contact model and used "[weak self]" in closure of "fetchContact()" method in controller while fetching data to avoid retain cycle. But still I got memory leak warning in line : "self?.append?.append(contact)". I observed the leak from instrument in Xcode 8.3.3.

I am confused why there is still strong reference of Contact in controller class.

Answer 1

In your case you are using for loop for parsing dictionary. So , you can release memory inside for loop by using autorelease

Write this inside for loop , this will release memory everytime loop is called.

autoreleasepool {
  /* code */ 
}