Cov txheej txheem:
Video: NSOperation thiab Nsoperationqueue yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
NSOperation and NSOperationQueue Txhawm rau txhim kho Concurrency hauv iOS. Kev ua haujlwm tuaj yeem ua rau muaj kev sib koom ua ke. Kev ua haujlwm yog ib txoj hauv kev taw qhia ntawm txoj haujlwm encapsulation, uas yog yuav tsum tau ua asynchronously. Kev ua haujlwm yuav tsum tau siv ua ke nrog kev ua haujlwm ua haujlwm lossis ntawm nws tus kheej.
Tsis tas li ntawd, NSOperation hauv Swift yog dab tsi?
NSOoperation yog chav kawm paub daws teeb meem uas tsis tuaj yeem siv ncaj qha yog li koj yuav tsum siv NSOoperation subclass. Hauv iOS SDK, peb tau muab ob qho tib si subclasses ntawm NSOoperation . Cov chav kawm no tuaj yeem siv ncaj qha, tab sis koj tuaj yeem ua tau subclass NSOoperation thiab tsim koj tus kheej chav kawm los ua cov haujlwm.
Ib tug kuj yuav nug, dab tsi yog kev ua haujlwm queue? Ib kev ua haujlwm kab executes nws ua haujlwm queued cov khoom raws li lawv qhov tseem ceeb thiab kev npaj txhij. Koj tsis tuaj yeem tshem tawm ncaj qha kev ua haujlwm los ntawm a kab tom qab nws tau ntxiv lawm. Nco tseg. Kev ua haujlwm queues khaws cia kev ua haujlwm mus txog thaum lawv ua tiav, thiab kab lawv tus kheej tau khaws cia kom txog thaum tag nrho kev ua haujlwm tiav lawm.
Tsuas yog li ntawd, qhov txawv ntawm NSOperationQueue thiab GCD yog dab tsi?
GCD yog qib qis C-raws li API. NSOoperation thiab NSOperationQueue yog cov chav kawm Objective-C. NSOperationQueue yog lub hom phiaj C wrapper tshaj GCD . Yog koj siv NSOoperation , ces koj yog implicitly siv Grand Central Dispatch.
Dab tsi yog txoj hauv kev ua kom tau txais txiaj ntsig zoo hauv iOS?
Muaj peb txoj hauv kev kom ua tiav concurrency hauv iOS:
- Xov.
- Dispatch queues.
- Kev ua haujlwm queues.
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