KVO yog dab tsi hauv Swift?
KVO yog dab tsi hauv Swift?

Video: KVO yog dab tsi hauv Swift?

Video: KVO yog dab tsi hauv Swift?
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KVO , uas sawv cev rau Key-Value Observing, yog ib qho ntawm cov txheej txheem rau kev soj ntsuam cov kev hloov hauv lub xeev muaj nyob rau hauv Objective-C thiab Swift . Lub tswvyim yog yooj yim: thaum peb muaj ib yam khoom nrog ib co piv txwv variables, KVO tso cai rau lwm yam khoom los tsim kev soj ntsuam ntawm kev hloov pauv rau ib qho ntawm cov piv txwv no.

Ib yam li ntawd, tib neeg nug, KVC thiab KVO hauv Swift yog dab tsi?

Flow ntawm qhov kev pab cuam nyob ntawm tus nqi ntawm ntau yam sib txawv peb siv hauv peb cov cai. Lwm txoj hauv kev uas zoo dua Hauv qhov xwm txheej no yog (tseem Apple siv qhov no hauv nws cov tsev qiv ntawv ntau) hu ua KVO (Key Value Observing), uas kuj yog ncaj qha cuam tshuam rau lwm lub hwj chim mechanism hu ua KVC (Key Value Coding).

Tsis tas li ntawd, tus nqi tseem ceeb coding hauv iOS yog dab tsi? Txog Ntsiab - Tus nqi Coding . Ntsiab - tus nqi coding yog ib lub tshuab ua haujlwm los ntawm NSKeyValueCoding cov txheej txheem tsis raws cai uas cov khoom siv los muab kev nkag tsis ncaj rau lawv cov khoom. Thaum twg yog qhov khoom tus yuam sij - tus nqi coding Raws li txoj cai, nws cov khoom muaj nyob ntawm txoj hlua tsis sib xws los ntawm cov ntsiab lus sib txuas lus sib xws.

Tom qab ntawd, KVO yog dab tsi hauv iOS?

Swift 4 Xcode 9 iOS no 11. Kev Saib Xyuas Qhov Tseem Ceeb, KVO luv luv, yog lub ntsiab lus tseem ceeb ntawm Cocoa API. Nws tso cai rau cov khoom raug ceeb toom thaum lub xeev ntawm lwm yam khoom hloov.

Dab tsi yog dynamic hauv Swift?

dynamic . Cov dynamic lo lus tseem ceeb yog kev tshaj tawm kev hloov kho uas koj tuaj yeem siv rau kev ua haujlwm lossis cov lus tshaj tawm sib txawv. Raws li ib qho tseem ceeb, txhua yam uas siv lub dynamic lo lus tseem ceeb siv lub hom phiaj-C runtime es tsis txhob ntawm lub Swift runtime xa cov lus rau nws.

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