@class NSMutableDictionary, NSObject; @protocol OS_dispatch_queue; @interface PLActivityScheduler : NSObject @property (retain) NSMutableDictionary *activities; @property (retain) NSObject<OS_dispatch_queue> *workQueue; + (id)sharedInstance; - (id)init; - (void)cancelActivityWithIdentifier:(id)a0; - (void)scheduleActivityWithIdentifier:(id)a0 withCriteria:(id)a1 withMustRunCriterion:(id)a2 withQueue:(id)a3 withInterruptBlock:(id /* block */)a4 withActivityBlock:(id /* block */)a5; - (void).cxx_destruct; - (id)lastCompletedDateWithIdentifier:(id)a0; @end