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4 Cards in this Set
- Front
- Back
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What is the difference between serial and concurrent queues? |
Serial: one closure at a time Concurrent: multiple threads servicing the queue |
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What are the restrictions for the main queue? |
All UI updates must happen on main queue. Time-consuming non-UI activity should happen off the main queue |
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How do you get a reference to the main queue? |
DispatchQueue.main |
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How do you get a global or background queue? |
DispatchQueue.global(qos: DispatchQos) |
