Multithreading and Grand Central Dispatch on iOS [closed]

问题

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Closed 6 years ago.

now i am trying to understand the concept of gcd. using grand central dispatch how to implement multithreading in my application.i have the idea about the gcd concept but i cant implement the concept to my application.i need a simple example with blocks to understand the multithreading using gcd.please help me...

回答1:

Ok.. The most simple example )

You can write this code in any method. For example

  -(void) viewDidLoad {   
     [super viewDidLoad];  
     dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
       //Here your non-main thread.
       NSLog (@"Hi, I'm new thread");
       dispatch_async(dispatch_get_main_queue(), ^{
       //Here you returns to main thread.
       NSLog (@"Hi, I'm main thread");
       });
   });
}

回答2:

Try this, its very clear and easy - http://en.wikipedia.org/wiki/Grand_Central_Dispatch

来源：https://stackoverflow.com/questions/15199342/multithreading-and-grand-central-dispatch-on-ios