arrays - firebase 子值作为数组中的字符串来填充选择器 swift 3

Question

您如何使用已放入数组中的 Firebase 值来填充选择器。这是我用来向数组添加值并打印它们的代码:

let dbRef1 = FIRDatabase.database().reference().child("Live Scoring Male")

    dbRef1.observe(.childAdded, with: { snapshot in

        let data = snapshot.value as? [String:Any] ?? [:]
        let name = data["name"] as? String ?? ""
        self.compArray.append(name)
        print("\(name)")

    })

然而，当我调用时，数组值没有被加载到选择器中:

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {

    if (pickerView.tag == 1) {
        return compArray[row]
    }
}

如果我对数组中的字符串进行硬编码，则此代码有效，但如果我尝试从 Firebase 加载值，则无效。

Answer 1

您需要重新加载 pickerView 组件以使用新的数据源数组更改它。

let dbRef1 = FIRDatabase.database().reference().child("Live Scoring Male")

dbRef1.observe(.childAdded, with: { snapshot in

    if let dic = snapshot.value as? [String:Any], let name = dic["name"] as? String { 
        self.compArray.append(name) 
        print("\(name)")

        //Reload the pickerView components
        self.pickerView.reloadAllComponents()

        //Or you can reload the pickerView's specific component
        self.pickerView.reloadComponent(0)
    }
})