RWTaskKit

Background

As we know, a UIApplication instance of an App calls delegate methods to notify developers implementing customizations. In these delegate methods, we can perform our tasks:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // do your massive stuff.....
    
    return YES;
}

For a sophisticated application, this would be a disaster for a developer to maintain.

RWTaskKit is born to solve this issue! It helps programmers to perform tasks separately. Forget AppDelegate from now on!

Perform task neatly!

Quick examle

Here is an examle for a task defined in a .m file:

@task(Task1, RWTaskPriorityCritical, RWTaskEventWillFinishLaunching)
+(void) run {
    NSLog(@"This is No.1 task we want to perform!");
}
@end

method run will be invoked right after application:willFinishLaunchingWithOptions: is called by UIApplication. This code snippet could be in any .m file only with importing RWTask.h

You can see that each task consists of three parts: task identifier with parameters task body task end identifier.

• task identifier with parameters

1. start with @ character just like annotation in Java
2. followed by a keyword identifying type of task
3. followed by a set of parameters

• task body

  consists of one or two objective-c class method.

• task end identifier

  just an end

RWTaskKit supports three types of task:event task schedule task notification task

Event task

Event task is designed to handle common methods calling in UIApplicationDelegate.

Parameters in the brackets are :Task Name, Priority, Event Name

Task Nanme would be any unique string. Priority would be enumeration value witch can be found in RWTaskObject.h, task (for a same event) with higher priority will be exexuted earlier.

Event Name would be enumeration value as following：

typedef NS_ENUM(NSUInteger, RWTaskEvent) {
  RWTaskEventWillFinishLaunching = 0x1,       //tasks will be performed only once
  RWTaskEventDidFinishLaunching = 0x1 << 1,   //tasks will be performed only once
  RWTaskEventWillEnterForeground = 0x1 << 2,
  RWTaskEventDidEnterBackground = 0x1 << 3,
  RWTaskEventDidBecomeActive = 0x1 << 4,
  RWTaskEventDidReceiveMemoryWarning = 0x1 << 5,
  RWTaskEventWillTerminate = 0x1 << 6,
  RWTaskEventWillResignActive = 0x1 << 7,
  RWTaskEventSignificantTimeChange = 0x1 << 8,
  RWTaskEventOpenURL = 0x1 << 9,
  RWTaskEventWillChangeStatusBarOrientation = 0x1 << 10,
  RWTaskEventDidChangeStatusBarOrientation = 0x1 << 11,
  RWTaskEventBackgroundRefreshStatusDidChange = 0x1 << 12,
  RWTaskEventUserDidTakeScreenshot = 0x1 << 13,
  RWTaskEventReserved1 = 0x1 << 14,
  RWTaskEventReserved2 = 0x1 << 15,
  RWTaskEventIdle = 0x1 << 16, // not implemented
  RWTaskEventNone = 0,
};

Above event enumerations are mapped to coresponding delegate methods. see UIApplication.h in iOS SDK.

class method run is a must-have for any task. Besides event task has an optional method +(NSArray<Class>*)dependency which denotes the dependency of the task. See the following example:

@task(Task2, RWTaskPriorityCritical, RWTaskEventWillFinishLaunching)
+(void) run {
    NSLog(@"This is No.2 task we want to perform!");
}
+(NSArray<Class>*)dependency{
  	// this task will be executed after Task1 and Task3 finish
	return @[task_name(Task1),task_name(Task3)];    
}
@end

Here task_name is a macro for convenience. Tasks specified in method dependency have nothing to do with the order inside the array.

Schedule task

Schedule task is designed for the task should be executed right after a scheduled time or repeated with specified times.

examples:

@schedule(ScheduleTask1, 1448873913, 5, 1)
+ (void) run{
  NSLog(@"hello");
}
@end
 
@timer(ScheduleTask2, 10, 2)
+ (void) run{
  NSLog(@"hello");
}
@end

ScheduleTask1 will be executed right after 1448873913(timestamp, like [[NSDate date] timeIntervalSince1970]), it will be executed 5 times for every 1 second.

ScheduleTask2 will be executed every 2 seconds, and it will repeat 10 times.

Schedule task has a built-in clock, the time interval is 1 second. Thus the timeinterval in paramters should be an integral multiple of built-in time interval. Besides the maximum timeinterval is 120 * built-in time interval.

Note: developers can customize the built-in time interval by trigger a repeatedly notification implused by your own NSTimer.

First, use NO_RW_CLOCK macro only once in any .m file. Second, post a notification with name RWAppClockTicktockNotificationKey in your customized timer.

Notification task

Notification task is designed for task should be triggered by a notification. Example:

@notification(NotiTask,@"NotificationKey")
+ (void) runWithNotification:(NSNotification*)noti{
  NSLog(@"hello");
}
@end

Runtime injection

Following interfaces can be used in runtime scenario to inject event tasks and schedule tasks.

- (void)injectEventTaskWithName:(NSString *)taskName
                  andBlock:(RWTaskBlock)block
                  priority:(RWTaskPriority)p
              triggerEvent:(RWTaskEvent)e
                dependency:(NSArray<Class> *)dependency
                autoRemove:(BOOL)autoRemove;
		
- (void)scheduleTaskWithName:(NSString *)taskName
                    andBlock:(RWTaskBlock)block
                 desiredDate:(NSDate *)date
                 repeatCount:(NSInteger)count
                timeInterval:(NSUInteger)timeInterval;

- (void)destroyTaskByName:(NSString *)taskName;

- (void)pauseTaskByName:(NSString *)taskName;

- (void)resumeTaskByName:(NSString *)taskName;