ios - 设置 CheckBox 开 - 关

Question

我通过创建一个 UIButton 类创建了一个带有按钮的自定义复选框这是类(class)

import UIKit

class CheckBox: UIButton {
    // Images
    let checkedImage = UIImage(named: "ic_check_box")! as UIImage
    let uncheckedImage = UIImage(named: "ic_check_box_outline_blank")! as UIImage

    // Bool property
    var isChecked: Bool = false {
        didSet{
            if isChecked == true {
                self.setImage(checkedImage, forState: .Normal)
            } else {
                self.setImage(uncheckedImage, forState: .Normal)
            }
        }
    }

    override func awakeFromNib() {
        self.addTarget(self, action: "buttonClicked:", forControlEvents: UIControlEvents.TouchUpInside)
        self.isChecked = false
    }

    func buttonClicked(sender: UIButton) {
        if sender == self {
            isChecked = !isChecked
        }
    }
}

我在 viewcontroller 中有两个复选框，但我不知道如何在 ViewController.class 中设置复选框以在选中复选框“Si”时执行操作，复选框“No”设置为未选中，如图中所示

Answer 1

您的 CheckBox 类应该采用委托(delegate)模式，以便它可以通知其委托(delegate)(在本例中是您的 View Controller )其值已更改。然后在您的 View Controller 中，您可以根据需要更新另一个复选框:

protocol CheckBoxDelegate {
    func checkBoxDidChange(checkbox: CheckBox) -> Void
}

class CheckBox: UIButton {
    // Images
    let checkedImage = UIImage(named: "ic_check_box")! as UIImage
    let uncheckedImage = UIImage(named: "ic_check_box_outline_blank")! as UIImage

    weak var delegate: CheckBoxDelegate? 
    // Bool property
    var isChecked: Bool = false {
        didSet{
            if isChecked == true {
                self.setImage(checkedImage, forState: .Normal)
            } else {
                self.setImage(uncheckedImage, forState: .Normal)
            }
        }
    }

    override func awakeFromNib() {
        self.addTarget(self, action: "buttonClicked:", forControlEvents: UIControlEvents.TouchUpInside)
        self.isChecked = false
    }

    func buttonClicked(sender: UIButton) {
        isChecked = !isChecked
        self.delegate?.checkBoxDidChange(self)
    }
}

然后，在您的 View Controller 中:

class ViewController: UIViewController, CheckBoxDelegate {

    @IBOutlet var siCheckBox: CheckBox!   // Initialise some other way if you aren't using storyboard/nib
    @IBOutlet var noCheckBox: CheckBox!

    override func viewDidLoad() {
        super.viewDidLoad()

        self.siCheckBox.delegate = self
        self.noCheckBox.delegate = self
    }

    //Mark: CheckBoxDelegate

    func checkBoxDidChange(checkbox: CheckBox) {
        if checkbox == self.siCheckBox {
            self.noCheckBox.isChecked = !checkbox.isChecked
        } else {
            self.siCheckBox.isChecked = !checkbox.isChecked
        }
    }

从用户体验的角度来看，我会质疑为什么需要两个复选框。复选框是一个开/关控件，因此您通常会看到“选择非常好的选项？”之类的文本。带有一个用于是/否的复选框；选中是，未选中是否。