Merge pull request #754 from woocommerce/issue/751-crash-on-log-out

Issue/751 crash on log out

Author: mindgraffiti

RELEASE-NOTES.txt

@@ -1,5 +1,6 @@
 1.4
 -----
+- bugfix: fix a crash happening on log out
 - new feature: Add shipment tracking to Order Details screen
 - improvement: The store switcher now allows you to go back to the previous screen without logging you out
 - improvement: Custom order status labels are now supported! Instead of just displaying the order status slug and capitalizing the slug, the custom order status label will now be fetched from the server and properly displayed.

WooCommerce/Classes/System/SessionManager.swift

@@ -12,6 +12,10 @@ extension NSNotification.Name {
     ///
     public static let defaultAccountWasUpdated = Foundation.Notification.Name(rawValue: "DefaultAccountWasUpdated")
 
+    /// Posted after a Log out event happens.
+    ///
+    public static let logOutEventReceived = Foundation.Notification.Name(rawValue: "LogOutEventReceived")
+
     /// Posted whenever the app is about to terminate.
     ///
     public static let applicationTerminating = Foundation.Notification.Name(rawValue: "ApplicationTerminating")

WooCommerce/Classes/ViewRelated/Orders/OrdersViewController.swift

@@ -195,6 +195,16 @@ private extension OrdersViewController {
     /// Setup: Order status predicate
     ///
     func refreshStatusPredicate() {
+        // Bugfix for https://github.com/woocommerce/woocommerce-ios/issues/751.
+        // Because we are listening for default account changes,
+        // this will also fire upon logging out, when the account
+        // is set to nil. So let's protect against multi-threaded
+        // access attempts if the account is indeed nil.
+        guard StoresManager.shared.isAuthenticated,
+            StoresManager.shared.needsDefaultStore == false else {
+                return
+        }
+
         statusResultsController.predicate = NSPredicate(format: "siteID == %lld", StoresManager.shared.sessionManager.defaultStoreID ?? Int.min)
     }
 
@@ -291,11 +301,12 @@ extension OrdersViewController {
     func startListeningToNotifications() {
         let nc = NotificationCenter.default
         nc.addObserver(self, selector: #selector(defaultAccountWasUpdated), name: .defaultAccountWasUpdated, object: nil)
+        nc.addObserver(self, selector: #selector(stopListeningToNotifications), name: .logOutEventReceived, object: nil)
     }
 
     /// Stops listening to all related Notifications
     ///
-    func stopListeningToNotifications() {
+    @objc func stopListeningToNotifications() {
         NotificationCenter.default.removeObserver(self)
     }
 

WooCommerce/Classes/Yosemite/StoresManager.swift

@@ -123,6 +123,8 @@ class StoresManager {
         ZendeskManager.shared.reset()
         AppDelegate.shared.storageManager.reset()
 
+        NotificationCenter.default.post(name: .logOutEventReceived, object: nil)
+
         return self
     }