fixes issues where the scheduled timer failed

LeStorage/StoredCollection.swift

@@ -500,8 +500,8 @@ public class StoredCollection<T: Storable>: SomeCollection {
 
     /// Schedules a write operation
     fileprivate func _scheduleWrite() {
-        DispatchQueue(label: "lestorage.queue.write", qos: .utility).asyncAndWait {
-            self._cleanTimer()
+        self._cleanTimer()
+        DispatchQueue.main.async {
             self._writingTimer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(self._write), userInfo: nil, repeats: false)
         }
     }
@@ -513,13 +513,15 @@ public class StoredCollection<T: Storable>: SomeCollection {
 
     /// Writes all the items as a json array inside a file
     @objc fileprivate func _write() {
-        do {
-            let jsonString: String = try self.items.jsonString()
-            try self.store.write(content: jsonString, fileName: T.fileName())
-        } catch {
-            Logger.error(error)
-            self.storeCenter.log(
-                message: "write failed for \(T.resourceName()): \(error.localizedDescription)")
+        DispatchQueue(label: "lestorage.queue.write", qos: .utility).async {
+            do {
+                let jsonString: String = try self.items.jsonString()
+                try self.store.write(content: jsonString, fileName: T.fileName())
+            } catch {
+                Logger.error(error)
+                self.storeCenter.log(
+                    message: "write failed for \(T.resourceName()): \(error.localizedDescription)")
+            }
         }
         self._cleanTimer()
     }