Video: Cov ntaub ntawv chav kawm Kotlin yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Kotlin muaj kev daws teeb meem zoo dua rau chav kawm uas yog siv los tuav cov ntaub ntawv / xeev. Nws hu ua a Data Class . A Data Class zoo li ib txwm chav kawm tab sis nrog qee qhov kev ua haujlwm ntxiv. Nrog Kotlin cov chav kawm cov ntaub ntawv , koj tsis tas yuav sau / tsim tag nrho cov ntawv ntev boilerplate koj tus kheej.
Ib yam li ntawd, Data Class yog dab tsi?
A chav kawm ntaub ntawv hais txog a chav kawm uas muaj tsuas yog teb thiab crude txoj kev nkag mus rau lawv (getters thiab setters). Cov no tsuas yog ntim rau cov ntaub ntawv siv los ntawm lwm tus chav kawm . Cov no chav kawm tsis muaj kev ua haujlwm ntxiv thiab tsis tuaj yeem ua haujlwm ntawm tus kheej cov ntaub ntawv uas lawv muaj.
Qhov thib ob, dab tsi yog cia hauv Kotlin? Kotlin ua yog ib txoj haujlwm scoping uas qhov sib txawv uas tau tshaj tawm hauv qhov kev qhia tsis tuaj yeem siv sab nraud. Ib qho piv txwv qhia kob let muaj nuj nqi yog muab hauv qab no.
Kuj kom paub, cov chav kawm cov ntaub ntawv puas tuaj yeem tau txais Kotlin?
Keeb kwm . Cov chav kawm ntaub ntawv hauv Kotlin yog kawg ntawm lub neej ntawd thiab ua tau 'tsis tau qhib kom peb ua tau tsis siv qub txeeg qub teg zoo li peb ua hauv Java lossis nrog ib txwm Cov chav kawm Kotlin . Yog li hauv Kotlin , peb ua tau yooj yim muaj peb Cov Neeg Laus thiab Me Nyuam cov ntaub ntawv kawm siv tus neeg thiab overriding cov khoom nyob rau hauv lub constructor ncaj qha.
Kev siv cov qauv hauv chav kawm hauv Android yog dab tsi?
ViewModel Txheej txheem cej luam Ib feem ntawm Android Dav hlau. Lub ViewModel chav kawm yog tsim los khaws thiab tswj cov ntaub ntawv ntsig txog UI hauv txoj kev paub txog lub neej. Lub ViewModel chav kawm tso cai rau cov ntaub ntawv kom ciaj sia cov kev hloov pauv xws li kev sib hloov ntawm lub vijtsam.
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