ios - UIPickerView +核心数据

用答案更新

import UIKit
import CoreData

class ExerciseViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, UIPickerViewDataSource, UIPickerViewDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()

        VDL()

        //sets stepper configs
        setsStepper.wraps = false
        setsStepper.autorepeat = true
        setsStepper.continuous = true
        setsStepper.tintColor = UIColor.redColor()
        setsStepper.minimumValue = 0
        setsStepper.maximumValue = 500
        setsStepper.value = 0

        //reps stepper configs
        repsStepper.wraps = false
        repsStepper.autorepeat = true
        repsStepper.continuous = true
        repsStepper.tintColor = UIColor.orangeColor()
        repsStepper.minimumValue = 0
        repsStepper.maximumValue = 500
        repsStepper.value = 0

        exerciseTableView.reloadData()
    }

    var moc = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext

    var fetchedResultsController: NSFetchedResultsController?

    @IBOutlet var exerciseTableView: UITableView!

    @IBOutlet var daysPickerView: UIPickerView!

    @IBOutlet var exerciseName: UITextField!
    @IBOutlet var setsStepper: UIStepper!
    @IBOutlet var repsStepper: UIStepper!

    @IBOutlet var setsNumber: UILabel!
    @IBOutlet var repsNumber: UILabel!

    var namesArray = [String]()
    var setsArray = [Int]()
    var repsArray = [Int]()
    var daysArray = [TrainingDay]()
    var detailsArray = [TrainingDetails]()

    func VDL () {
        let fetchRequest = NSFetchRequest(entityName: "TrainingDay")
        let sort = NSSortDescriptor(key: "dayIndex", ascending: true)
        fetchRequest.sortDescriptors = [sort]
        daysArray = (moc!.executeFetchRequest(fetchRequest, error: nil) as? [TrainingDay])!
        if daysArray.count == 0 { // nothing there
            let dayEntity = NSEntityDescription.entityForName("TrainingDay", inManagedObjectContext: moc!)
            let days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]
            for (index, name) in enumerate(days) {
                let newDay = TrainingDay(entity: dayEntity!, insertIntoManagedObjectContext: moc)
                newDay.day = name
                newDay.dayIndex = index
                daysArray.append(newDay)
            }
            var error: NSError?
            moc!.save(&error)
        }

    }


    func appendTrainingDetailsToArray () {
        let nameLabel = exerciseName.text
        namesArray.append(nameLabel)
        let numberOfSets = setsNumber.text?.toInt()
        setsArray.append(numberOfSets!)
        let numberOfReps = repsNumber.text?.toInt()
        repsArray.append(numberOfReps!)

        let row = daysPickerView.selectedRowInComponent(0)
        let currentDay = daysArray[row]


        let detailsEntity = NSEntityDescription.entityForName("TrainingDetails", inManagedObjectContext: moc!)
        let trainingdetails = TrainingDetails(entity: detailsEntity!, insertIntoManagedObjectContext: moc)
        trainingdetails.trainingDay = currentDay

        var error: NSError?
        moc?.save(&error)

        if let err = error {
            var status = err.localizedFailureReason
            println("\(status)")
        } else {
            println("CURRENT SETTING: \(trainingdetails.trainingDay)")
        }
    }

    @IBAction func doneButton(sender: AnyObject) {
        appendTrainingDetailsToArray()

        exerciseTableView.reloadData()
    }

    @IBAction func setsStepperAction(sender: UIStepper) {
        println("\(Int(sender.value))")
        setsNumber.text = Int(sender.value).description
    }

    @IBAction func repsStepper(sender: UIStepper) {
        println("\(Int(sender.value))")
        repsNumber.text = Int(sender.value).description
    }

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return namesArray.count
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        let cellIdentifier = "exerciseCell"
        var cell  = tableView.dequeueReusableCellWithIdentifier(cellIdentifier) as? UITableViewCell
        if cell == nil {
            cell = UITableViewCell(style: UITableViewCellStyle.Value2, reuseIdentifier: cellIdentifier)
        }
        let row = indexPath.row
        println("\(row)")
        let details = detailsArray[indexPath.row]
        cell!.textLabel!.text = details.exerciseName
        cell?.detailTextLabel?.text = "Sets: #\(details.setsNumber) Reps: #\(details.repsNumber)"
        return cell!
    }

    //PICKER VIEW DELEGATE AND DATASOURCE METHODS
    func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
        return 1
    }

    func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return daysArray.count
    }

    func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
            let trainingDay = daysArray[row]
            return trainingDay.day
    }

    func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {

        let currentDay = daysArray[row]
        let fetchRequest = NSFetchRequest(entityName: "TrainingDetails")
        let predicate = NSPredicate(format: "trainingDay = %@", currentDay)
        fetchRequest.predicate = predicate
        let sort = NSSortDescriptor(key: "exerciseName", ascending: true)
        fetchRequest.sortDescriptors = [sort]
        detailsArray = (moc!.executeFetchRequest(fetchRequest, error: nil) as? [TrainingDetails])!
        exerciseTableView.reloadData()

    }
}

以前，我曾寻求帮助，因此可以适应UIPickerView。
就像@pbasdf所说的那样，代码需要进行一些调整以符合核心数据和选择器视图。您可以在他的回答中看到他的解释!

最佳答案

有几件事要解决:

TrainingDay实体

您对awakeFromInsert代码的选择是错误的。它不会插入新对象；只要您插入新的TrainingDay对象，它就会运行。从我在您的代码中看到的，您实际上从未插入新的TrainingDays(这很幸运，因为awakeFromInsert将崩溃-您正在将字符串数组分配给作为字符串的属性)。

您需要创建7个TrainingDay对象，一周中的每一天一个。由于这些不会更改，因此您可以在首次运行应用程序时将其作为一项一次性任务来完成，或者在尝试获取它们时(如下面所述)“懒惰”地完成。您不需要awakeFromInsert代码，但是我建议向该实体添加另一个属性，例如“dayIndex”，这将使您能够将TrainingDay对象按逻辑顺序排序。您的代码可能看起来像这样:

// load the TrainingDays data...
let fetchRequest = NSFetchRequest(entityName: "TrainingDay")
let sort = NSSortDescriptor(key: "dayIndex", ascending: true)
fetchRequest.sortDescriptors = [sort]
daysArray = (moc!.executeFetchRequest(fetchRequest, error: nil) as? [TrainingDay])!
if daysArray.count == 0 { // nothing there
    let dayEntity = NSEntityDescription.entityForName("TrainingDay", inManagedObjectContext: moc!)
    let days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]
    for (index, name) in enumerate(days) {
        let newDay = TrainingDay(entity: dayEntity!, insertIntoManagedObjectContext: moc)
        newDay.day = name
        newDay.dayIndex = index
        daysArray.append(newDay)
    }
    moc.save(&error)
}

您可以将其放在viewDidLoad或VDL调用的函数中。然后，您可以将daysArray用作选择器视图的数据源...

填充选择器视图

放弃daysOfPickerView，改为使用daysArray ...

//PICKER VIEW DELEGATE AND DATASOURCE METHODS
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
    return 1
}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return daysArray.count
}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
    let trainingDay = daysArray[row]
    return trainingDay.day
}

将TrainingDetails对象分配给正确的日期

在appendTrainingDetailsToArray方法中，您需要确定在选择器视图中当前选择的日期。为此，您将需要为pickerView添加@IBOutlet var并将其连接到情节提要中。然后您可以访问它并设置TrainingDetails的关系...

let row = pickerView.selectedRowInComponent(0)
let currentDay = daysArray[row]
trainingDetails.trainingDay = currentDay

填充表格视图
当前，您正在使用三个单独的阵列。我只会用一个:

var detailsArray = [TrainingDetails]()

然后使用TrainingDetails的属性来填充表格视图单元格，即。

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cellIdentifier = "exerciseCell"
    var cell  = tableView.dequeueReusableCellWithIdentifier(cellIdentifier) as? UITableViewCell
    if cell == nil {
        cell = UITableViewCell(style: UITableViewCellStyle.Value2, reuseIdentifier: cellIdentifier)
    }
    let row = indexPath.row
    let details = detailsArray[indexPath.row]
    cell!.textLabel!.text = details.exerciseName
    cell?.detailTextLabel?.text = "Sets: #\(details.setsNumber) Reps: #\(details.repsNumber)"
    return cell!
}

修改其他表视图数据源方法，以同样使用detailsArray。

您的三个数组当前是使用append...方法构建的，但是我想您想要的是在选定的日期使用正确的'TrainingDetails'填充表格视图...

响应于选择器视图更改

当前，每次选择器视图更改时，您的代码似乎都会创建新的TrainingDetails。相反，只需获取所选日期的TrainingDetails，然后重新加载表即可:

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    let currentDay = daysArray[row]
    let fetchRequest = NSFetchRequest(entityName: "TrainingDetails")
    let predicate = NSPredicate(format: "trainingDay = %@", currentDay)
    fetchRequest.predicate = predicate
    let sort = NSSortDescriptor(key: "exerciseName", ascending: true)
    fetchRequest.sortDescriptors = [sort]
    detailsArray = (moc!.executeFetchRequest(fetchRequest, error: nil) as? [TrainingDetails])!
    exerciseTableView.reloadData()
}

进一步的思考

您已经声明了NSFetchedResultsController，但没有使用它。使用它而不是原始的NSFetchRequest是有意义的，因为它将自动响应您添加新的TrainingDetails并将其添加到表中-而不需要使用reloadData()。但这是另一天...

另外，如果您会原谅我，那么您可以选择一些自由项:!和？。我将它们保留在复制代码的位置不变，但是您可以整理它们。同样，对于上下文操作使用error参数-总是值得使用它。就是说，我起草以上代码时并未在Xcode中对其进行测试，因此，如果我在某些地方犯了一些错误，请原谅。希望你能看到这个主意。