获取View的指定子视图

通过递归获取指定view的所有子视图.

1. 获取View的子视图

使用

    let subViewArr = view.getAllSubViews() // 获取所有子视图
    let imageViewArr = view.getSubView(name: "UIImageView") // 获取指定类名的子视图

实现

extension UIView {
    private static var getAllsubviews: [UIView] = []
    public func getSubView(name: String) -> [UIView] {
        let viewArr = viewArray(root: self)
        UIView.getAllsubviews = []
        return viewArr.filter {$0.className == name}
    }
    public func getAllSubViews() -> [UIView] {
        UIView.getAllsubviews = []
        return viewArray(root: self)
    }
    private func viewArray(root: UIView) -> [UIView] {
        for view in root.subviews {
            if view.isKind(of: UIView.self) {
                UIView.getAllsubviews.append(view)
            }
            _ = viewArray(root: view)
        }
        return UIView.getAllsubviews
    }
}

extension NSObject {
    var className: String {
        let name = type(of: self).description()
        if name.contains(".") {
            return name.components(separatedBy: ".")[1]
        } else {
            return name
        }
    }
}

2. 获取UIAlertController的titleLabel和messageLabel

UIAlertController好用,但可自定义程度不高,例如我们想让message文字左对齐,就需要获取到messageLabel,但UIAlertController并没有提供这个属性.

我们就可以通过递归拿到alertTitleLabel和alertMessageLabel.

extension UIAlertController {
    public var alertTitleLabel: UILabel? {
        return self.view.getSubView(name: "UILabel").first as? UILabel
    }
    public var alertMessageLabel: UILabel? {
        return self.view.getSubView(name: "UILabel").last as? UILabel
    }
}

虽然通过这种方法可以拿到alertTitleLabel和alertMessageLabel.但没法区分哪个是哪个,alertTitleLabel为默认子控件的第一个label,如果title传空,message传值,alertTitleLabel和alertMessageLabel获取到的都是message的label.

如果有更好的方法欢迎讨论.

本文收录于 SwiftTips