At the moment, using Bindable for an object stored in Environment works in a cumbersome way:
struct ContentView: View {
@Environment(Model.self) var model
var body: some View {
@Bindable var model = model
VStack {
Text(model.someField.uppercased())
TextField("", text: $model.someField)
someSubView
}
.padding()
}
@ViewBuilder
var someSubView: some View {
@Bindable var model = model
TextField("", text: $model.someField)
}
}
A new @Bindable needs to be instantiated for each computed property in the view, which creates boilerplate I would like to avoid.
I made a new property wrapper which functions the same as the EnvironmentObject wrapper, but for Observable:
@propertyWrapper
struct EnvironmentObservable<Value: AnyObject & Observable>: DynamicProperty {
@Environment var wrappedValue: Value
public init(_ objectType: Value.Type) {
_wrappedValue = .init(objectType)
}
public init() {
_wrappedValue = .init(Value.self)
}
private var store: Bindable<Value>!
var projectedValue: Bindable<Value> {
store
}
mutating func update() {
store = Bindable(wrappedValue)
}
}
Example:
struct ContentView: View {
@EnvironmentObservable var model: Model
var body: some View {
VStack {
Text(model.someField.uppercased())
SubView(value: $model.someField)
someSubView
}
.padding()
}
var someSubView: some View {
TextField("", text: $model.someField)
}
}
I was wondering if there would be any downsides to using this method? In my testings it seems to behave the same, but I'm not sure if using this could have a performance impact.