Swift Multi-Threading

person shubham sharmafolder_openiOS, MAC Os, Swiftlocal_offeriOS, Mac OS, Swiftaccess_time April 6, 2019

1- The Main Queue	2- The Global Queue:	3- Custom Queues:
Swift DispatchQueue.main.async { ... } 1 2 3 DispatchQueue.main.async {    ... }	Swift DispatchQueue.global(qos: .background).async { ... } 1 2 3 DispatchQueue.global(qos: .background).async { ... }	Swift let concurrentQueue = DispatchQueue(label: "queuename", attributes: .concurrent) concurrentQueue.sync { ... } <span style="font-family: inherit; font-size: inherit;"> </span> 1 2 3 4 let concurrentQueue = DispatchQueue(label: "queuename", attributes: .concurrent) concurrentQueue.sync { ... }  <span style="font-family: inherit; font-size: inherit;"> </span>
highest priority	1- userInteractive : Work is virtually instantaneous. Similar to main thread. 2- userInitiated : Work is nearly instantaneous, such as a few seconds or less. 3- default: don’t use it usually , the type will be inferred by the system 4- utility: Work takes a few seconds to a few minutes. 5- background: Work takes significant time, such as minutes or hours.
Update all UI	Do not update any UI DispatchQueue.global(qos: .background).async { ...//Dowload Image DispatchQueue.main.async { ...//Set image on imageview } } 1 2 3 4 5 6 DispatchQueue.global(qos: .background).async {    ...//Dowload Image    DispatchQueue.main.async {       ...//Set image on imageview    } }

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