UI depends on State of the View? How Data Flow works in SwiftUI..
In SwiftUI, data flow is handled through a reactive and declarative approach, where the UI state is determined by the app’s data. The primary data source, known as the “source of truth,” should ideally be situated near the top of the view hierarchy.
Each piece of data should have only one main source to avoid redundancy. SwiftUI employs various property wrappers such as @State, @Binding, @ObservedObject, @EnvironmentObject, and @Environment to manage different data dependencies and behaviours effectively. These wrappers ensure seamless synchronisation between UI and data modifications.
- @State: Manages simple local state within a single view. Ideal for small, view-specific data that SwiftUI handles and updates internally.
- @Binding: Allows a view to modify state owned by a parent view, establishing a two-way binding between them.
- @ObservedObject: Handles complex state shared across multiple views. Requires conformance to the
ObservableObjectprotocol, with observed properties marked as @Published. - @EnvironmentObject: Similar to
@ObservedObject, but passes data deep into the view hierarchy without explicit initialisation. - @Environment: Accesses system-wide information like Locale or TimeZone provided by the environment.
- Data trickles down from parent views to child views via initializers and environment configurations.
- Automatic view updates occur upon data modifications.
- Strive for stateless views whenever feasible, ensuring their presentation and actions correlate exclusively with the provided data.
Comprehending these data flow principles and utilising property wrappers is vital for crafting SwiftUI apps that boast clarity and maintainability. Adhering to these guidelines facilitates the creation of consistent and responsive UIs synchronised with your data model.
