如何访问视图控制器扩展中的视图

Question

self.view 出错，提示“UIViewController.Type”没有名为“view”的成员

extension UIViewController {

    class func addBackgroundImage() {
        let backgroundImageView = UIImageView();
        let backgroundImage = UIImage(named: "splashBackground");
        backgroundImageView.image = backgroundImage;
        self.view.addSubview(backgroundImageView);
        let insets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
        backgroundImageView.autoPinEdgesToSuperviewEdgesWithInsets(insets)
    }

Answer 1

您已将addBackgroundImage 定义为class func。这意味着self 将是类对象，而不是类的实例。

请改用func addBackgroundImage() { ... }。