简而言之
我想要延迟发布,但不知道如何将部分组合起来。
详细描述
我有一个 Publisher
。
let generator = PassthroughSubject<Bool, Never>()
并且想要以某种方式使用修饰符
.delay(for: 2, scheduler: RunLoop.main)
这样当我调用时
generator.send(true)
调用send()
后两秒钟发送消息。
查看Publishers.Delay
的文档使类型错误更清晰,但并不能帮助我找到正确的连接方式。
代码
import SwiftUI
import Combine
// Exists just to subscribe.
struct ContainedView : View {
private let publisher: AnyPublisher<Bool, Never>
init(_ publisher: AnyPublisher<Bool, Never> = Just(false).dropFirst().eraseToAnyPublisher()) {
self.publisher = publisher
}
var body: some View {
Rectangle().onReceive(publisher) { _ in print("Got it") }
}
}
struct ContentView: View {
let generator = PassthroughSubject<Bool, Never>()
// .delay(for: 2, scheduler: RunLoop.main)
// Putting it here doesn't work either.
var body: some View {
VStack {
Button("Tap") {
// Does not compile
self.generator.delay(for: 2, scheduler: RunLoop.main).send(true)
// Value of type 'Publishers.Delay<PassthroughSubject<Bool, Never>, RunLoop>' has no member 'send'
// https://developer.apple.com/documentation/combine/publishers/delay
// Does not compile
self.generator.send(true).delay(for: 2, scheduler: RunLoop.main)
// Value of tuple type '()' has no member 'delay'
// Just a broken-up version of the first try.
let delayed = self.generator.delay(for: 2, scheduler: RunLoop.main)
delayed.send(true)
// This, of course, builds and works.
self.generator.send(true)
print("Sent it")
}
ContainedView(generator.eraseToAnyPublisher())
.frame(width: 300, height: 200)
}
}
}