如何使用 UIAlertController 在 Swift 暂停代码并等待 UIAlert 的回答

Question

我不得不说我已经在堆栈溢出中搜索了答案，但找不到，所以这就是我问它的原因...

**

• 我的问题： 我的问题是 - 我正在制作一个番茄钟应用程序，我让 用户设置 TimeLabel（时间），现在如果用户在会话中， 他想改变他能够做到的时间，尽管如果他 尝试这样做，一旦他改变了时间并想取消 它，用户当然能够做到，现在的问题是我 使用 UiAlertController 等待用户的回答，但其中 我还使用更新设置的功能 Labels/Parameters.

**

我的代码： 我的更新设置函数：

//Updating the UserSettings:
func updateSettingsLabels(cell: PickerTableViewCell, rowIndex: Int) {
    let identifier = cell.reuseIdentifier

    switch identifier {
    case T.Identifiers.workIntervalID:
        workInterval.text = timesDictionary[rowIndex]
        self.workIntervalString = timesDictionary[rowIndex] // set string
        
        let myString = workInterval.text!
        oldTime = workInterval.text! // setting up the old time
        
        saveTime(labelText: myString)
        
    case T.Identifiers.shortBreakID:
        shortBreak.text = timesDictionary[rowIndex]
        self.shortBreakString = timesDictionary[rowIndex] // set string
        saveShortBreak(breakText: shortBreak.text!)
        
    case T.Identifiers.longBreakTimeID:
        longBreakTime.text = timesDictionary[rowIndex]
        self.longBreakString = timesDictionary[rowIndex] // set string
        saveLongBreak(longBreakText: longBreakString!)
        
        
    case T.Identifiers.breakAfterIntervalsID: // after how much intervals we will take a long break
        longBreakAfter.text = intervalsDictionary[rowIndex]
        self.longBreakAfterIntervals = intervalsDictionary[rowIndex] // set string
        saveBreakAfterIntervals(breakAfterIntervals: longBreakAfterIntervals!)

        
    case T.Identifiers.dailyIntervalsID: // daily intervals
        dailyIntervals.text = intervalsDictionary[rowIndex]
        self.dailyIntervalsString = intervalsDictionary[rowIndex] // set string
        saveDailyIntervals(dailyIntervals: dailyIntervalsString!)
        
    
    default:
        print("There was a problem with Switch")
    }
    
    

我的 UiAlert 函数：

func alertTheUser() {
    //If we want to print something on the screen, we use UIAlertController:
    let alert = UIAlertController(title: "Do you want to aboard this task?", message: "Once you change the time in a middle of a session, you will reset all tasks.", preferredStyle: .alert)
    
    
    alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { (alertToCancel) in
        
        self.userWantToChangeSettings = false
        print("Im being changed!")
    }))

    alert.addAction(UIAlertAction(title: "Ok", style: .destructive, handler: { (action) in

        self.userWantToChangeSettings = true
    }))
    
    
    self.present(alert, animated: true)
}

我必须告诉你们，我也使用 UIPicker 让用户从可选时间中选择时间，这是我的代码：

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int, forCell cell: PickerTableViewCell) {

    
    if self.timerIsOnFire == true {
            self.alertTheUser()
            
    }
    
    
    updateSettingsLabels(cell: cell, rowIndex: row)
    
    
    self.delegate?.userSettings(interval: self.workIntervalString, shortBreak:self.shortBreakString, longBreak:self.longBreakString, breakAfterIntervals:self.longBreakAfterIntervals,dailyIntervals:self.dailyIntervalsString )
    
    
    self.view.endEditing(true)
    
}

Answer 1

像这样将 Alert 函数与完成处理程序一起使用

func alertTheUser(completion:@escaping ()->Void) {
    //If we want to print something on the screen, we use UIAlertController:
    let alert = UIAlertController(title: "Do you want to aboard this task?", message: "Once you change the time in a middle of a session, you will reset all tasks.", preferredStyle: .alert)
    
    
    alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { (alertToCancel) in
        
        self.userWantToChangeSettings = false
        print("Im being changed!")
         completion()
    }))

    alert.addAction(UIAlertAction(title: "Ok", style: .destructive, handler: { (action) in

        self.userWantToChangeSettings = true
        completion()
    }))
    
    
    self.present(alert, animated: true)
}