我正在尝试以编程方式将事件指示器置于警报 Controller 的中心,但没有看到预期的结果。
尝试:
import NVActivityIndicatorView
public func displayActivityAlertWithCompletion(ViewController: UIViewController, pending: UIAlertController, completionHandler: @escaping ()->())
{
//create an activity indicator
let indicator = NVActivityIndicatorView(frame: CGRect(x: (pending.view.frame.width/2) - 25 , y: 0, width: 50, height: 50))
//indicator.clipsToBounds = true
indicator.type = .ballScaleMultiple
indicator.autoresizingMask = \[.flexibleWidth, .flexibleHeight\]
indicator.color = UIColor(rgba: Palette.loadingColour)
//add the activity indicator as a subview of the alert controller's view
pending.view.addSubview(indicator)
indicator.isUserInteractionEnabled = false
// required otherwise if there buttons in the UIAlertController you will not be able to press them
indicator.startAnimating()
ViewController.present(pending, animated: true, completion: completionHandler)
}
最佳答案
您面临的问题在于这一行:
let indicator = NVActivityIndicatorView(frame: CGRect(x: (pending.view.frame.width/2) - 25 , y: 0, width: 50, height: 50))
此时您的pending
alert controller not 还没有出现,它的框架也没有更新。
在显示警报 Controller 后,您必须更新指标的 frame
,例如,您可以执行以下操作。
替换这一行:
ViewController.present(pending, animated: true, completion: completionHandler)
有了这个:
ViewController.present(pending, animated: true, completion: {
// update frame here:
indicator.frame = CGRect(x: (pending.view.frame.width/2) - 25 , y: 0, width: 50, height: 50)
// and manually call completionHandler:
completionHandler()
})
关于ios - 以编程方式将指示器 View 置于警报 Controller 中,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/51037753/