启动IOS应用程序时出现PromiseKit 6.0错误

Question

PromiseKit 6.0结构是否正确？因为我在运行应用程序时收到错误：（

这是图像：

 //Promise block
        firstly{
            removePreviusSearch(text)
            }.then {(finished) -> Promise<AI> in
                aiService.getAi()
            }.done {(ai) -> Void in
                self.updateResults(ai)
            }.catch { (error) in
                //catch error
    }

}

// MARK : Remove previus search
func removePreviusSearch(_ newText: String) -> Promise<Bool> {
    return Promise { seal in
        UIView.animate(withDuration: 0.5, animations:{
            self.topLabel.alpha = 0
            self.mainText.alpha = 0
            self.resultsView.alpha = 0
            self.textField.text = ""
        }, completion: { (finished: Bool) in
            UIView.animate(withDuration: 0.5) {
                self.topLabel.alpha = 1
                self.mainText.alpha = 1
            }
            seal.reject(finished as! Error)
            self.topLabel.text = "user says".uppercased()
            self.mainText.text = newText
            self.setLabel(self.cityLabel)
            self.setLabel(self.streetLabel)
            self.setLabel(self.countryLabel)
            self.setLabel(self.dateLabel)
            self.setLabel(self.speechLabel)
            self.setLabel(self.itentLabel)
            self.setLabel(self.conditionLabel)
            self.setLabel(self.outfitLabel)
            self.setLabel(self.scoreLabel)
        })
    }
}

Answer 1

      completion: { (finished: Bool) in
        ...
        seal.reject(finished as! Error) // casting error
        ... 

首先，已完成是一个布尔值，您无法强制将其强制转换为错误。如果您想拒绝错误，则应该如下所示初始化错误。

let error = NSError(domain: "some information", code: 0, userInfo: nil) as Error
reject(error)

其次，我不知道你为什么要在代码中间拒绝，它会破坏整个承诺链。在所有事情都正确完成后，您应该履行承诺。

    }, completion: { (finished: Bool) in
        UIView.animate(withDuration: 0.5) {
            self.topLabel.alpha = 1
            self.mainText.alpha = 1
        }
        self.topLabel.text = "user says".uppercased()
        self.mainText.text = newText
        self.setLabel(self.cityLabel)
        self.setLabel(self.streetLabel)
        self.setLabel(self.countryLabel)
        self.setLabel(self.dateLabel)
        self.setLabel(self.speechLabel)
        self.setLabel(self.itentLabel)
        self.setLabel(self.conditionLabel)
        self.setLabel(self.outfitLabel)
        self.setLabel(self.scoreLabel)

        // fulfill your promise right here
    })
...