Answer Posted / babu
Block: Block objects are a C-level syntactic and runtime feature. Blocks are particularly useful as a callback because the block carries both the code to be executed on callback (on completion handler block) and the data needed during that execution.
GCD: GCD (Grand Central Dispatch) provides and manages FIFO queues to which your application can submit tasks in the form of block objects. Blocks submitted to dispatch queues are executed on a set of threads completely managed by the system. No guarantee is made as to the thread on which a task executes. GCD allows three kinds of queues:
Main: tasks execute serially on your application’s main thread
Concurrent: tasks are dequeued in FIFO order, but run concurrently and can finish in any order.
Serial: tasks execute one at a time in FIFO order
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
What is delegate pattern in iOS?
What is meaning of 'retain' keyword?
What is iphone os?
What is mvvm in ios swift?
Do you know what is iphone sdk?
What are the lifecycle events of uiviewcontroller?
What is @dynamic in objective-c ?
What is strong and weak in ios?
What is singleton pattern in ios?
What are ios functions?
Explain me what is "delegate"?
Explain what is a framework?
What are the functions of managed object context?
What is messaging? What is message forwarding?
How do you decide when to use infinite scroll or pagination in ios? : IOS Architect
