ios - 观察多个controlEvent导致 `Reentrancy anomaly was detected.`警告信息

Question

我是 RxSwift 的新手，今天我遇到了一个我无法解决的问题。我想观察 UITextField 中的 controlEvent。

代码:

textField.rx
    .controlEvent([.editingDidEndOnExit, .editingDidEnd])
    .subscribe(onNext: { [weak self] in
        // do stuff
    })
    .disposed(by: disposeBag)

我想现在 textField 辞职成为第一响应者或用户点击 return 按钮。当我执行一行时，代码工作正常:textField.resignFirstResponder() 但是当我点击 return 按钮时，我收到一条警告消息:

⚠️ Reentrancy anomaly was detected. Debugging: To debug this issue you can set a breakpoint in /Users/laxmorek/Documents/projects/meetingapplication-ios/Pods/RxSwift/RxSwift/Rx.swift:97 and observe the call stack. Problem: This behavior is breaking the observable sequence grammar. next (error | completed)? This behavior breaks the grammar because there is overlapping between sequence events. Observable sequence is trying to send an event before sending of previous event has finished. Interpretation: This could mean that there is some kind of unexpected cyclic dependency in your code, or that the system is not behaving in the expected way. Remedy: If this is the expected behavior this message can be suppressed by adding .observeOn(MainScheduler.asyncInstance) or by enqueing sequence events in some other way.

我不明白这个。

• 在 RxSwift 中观察多个 controlEvent 的正确方法是什么？
• 为什么我会收到这条警告消息？我的观察设置有什么问题？

编辑

临时解决方法是我这样拆分我的代码:

textField.rx
    .controlEvent(.editingDidEndOnExit)
    .subscribe(onNext: { [weak self] in
        self?.isSelected = false
    })
    .disposed(by: disposeBag)
textField.rx
    .controlEvent(.editingDidEnd)
    .subscribe(onNext: { [weak self] in
        self?.isSelected = false
    })
    .disposed(by: disposeBag)

但是这个代码重复看起来不太好。 :/

Answer 1

这意味着事件是从不同的线程发送的。通过指定 MainScheduler.asyncInstance，您指定事件与 MainScheduler.asyncInstance 线程一起发送，这将避免 onNext 事件的并发问题。

试试这个:

textField.rx
    .controlEvent([.editingDidEndOnExit, .editingDidEnd])
    .observeOn(MainScheduler.asyncInstance)
    .subscribe(onNext: { [weak self] in
        // do stuff
    })
    .disposed(by: disposeBag)