quelle est la différence entre ObservableObject et StateObject
Generated on 9/6/2024
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La différence entre ObservableObject et StateObject dans SwiftUI réside principalement dans la manière dont ils gèrent l'état et les dépendances des vues.
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ObservableObject: C'est un protocole que vous pouvez adopter dans vos classes pour permettre à SwiftUI de surveiller les changements d'état. Lorsque vous utilisez
@ObservedObjectdans une vue, vous indiquez que la vue doit se mettre à jour lorsque l'objet observé change. Cependant, la vue ne gère pas le cycle de vie de l'objet observé. Cela signifie que vous devez vous assurer que l'objet reste en mémoire aussi longtemps que nécessaire. -
StateObject: Introduit pour résoudre certains des problèmes liés à
ObservableObject,@StateObjectest utilisé pour créer et gérer le cycle de vie d'un objet observable. Lorsque vous utilisez@StateObject, SwiftUI crée et conserve l'objet pour vous, garantissant qu'il reste en mémoire tant que la vue est en vie. C'est particulièrement utile pour les objets qui doivent être initialisés une seule fois et conservés tout au long de la durée de vie de la vue.
Pour plus de détails sur la gestion de l'état dans SwiftUI, vous pouvez consulter la session SwiftUI essentials.
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