在选择器视图swift 1.2中更改选定的行标签颜色

Question

我用以下代码创建了pickerview

    @IBOutlet var myPicker: UIPickerView!

    var colors: [String] = ["red","green","blue"]

    override func viewDidLoad() {
            super.viewDidLoad()     

            myPicker = UIPickerView()
            myPicker.dataSource = self
            myPicker.delegate = self
    }

    func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
            return 1
        }

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

    func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
            return colors[row] as! String
        }

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

        }

现在我想更改所选行的标签(文本)颜色,例如,如果我向下滚动并选择蓝色,文本颜色应更改为橙色,其他2个标签将为黑色,当我选择其他行时,相同.我尝试了以下代码,但它不起作用

func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView!) -> UIView {
        var pickerLabel = UILabel()
        var myTitle:NSAttributedString
        let titleData = colors[row]
        if pickerView.selectedRowInComponent(component) == row {
            myTitle = NSAttributedString(string: titleData, attributes: [NSForegroundColorAttributeName: UIColor.redColor()])
        } else {
            myTitle = NSAttributedString(string: titleData, attributes: [NSForegroundColorAttributeName: UIColor.blueColor()])
        }

        //This way you can set text for your label.
        pickerLabel.attributedText = myTitle

        return pickerLabel

    }

我不知道我是否应该用didSelectRow或viewForRow方法实现它,有人可以帮我这个吗？

Answer 1

你可以做以下的事情:

class ViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {

  var colors = ["red","green","blue"]

  func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
    return 1
  }

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

  func pickerView(pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
    let color = (row == pickerView.selectedRowInComponent(component)) ? UIColor.orangeColor() : UIColor.blackColor()
    return NSAttributedString(string: colors[row], attributes: [NSForegroundColorAttributeName: color])
  }

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