UIAlertController中的多行可编辑文本UITextview？

Question

如何在UITextview中制作多行可编辑文本UIAlertController？ UITextfield支持单行，我们需要在弹出窗口中创建一个多行文本编辑框。

Answer 1

这是好方法......

func popUpController()
{

    let alertController = UIAlertController(title: "\n\n\n\n\n\n", message: nil, preferredStyle: UIAlertController.Style.actionSheet)

    let margin:CGFloat = 8.0
    let rect = CGRect(x: margin, y: margin, width: alertController.view.bounds.size.width - margin * 4.0, height: 100.0)
    let customView = UITextView(frame: rect)

    customView.backgroundColor = UIColor.clear
    customView.font = UIFont(name: "Helvetica", size: 15)



    //  customView.backgroundColor = UIColor.greenColor()
    alertController.view.addSubview(customView)

    let somethingAction = UIAlertAction(title: "Something", style: UIAlertAction.Style.default, handler: {(alert: UIAlertAction!) in print("something")

        print(customView.text)

    })

    let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertAction.Style.cancel, handler: {(alert: UIAlertAction!) in print("cancel")})

    alertController.addAction(somethingAction)
    alertController.addAction(cancelAction)

    self.present(alertController, animated: true, completion:{})


}

Answer 2

我对Vishal的方法进行了一些调整。

1. 添加了UITextViewDelegate方法，将初始浅灰色文本显示为占位符，并在textViewDidBeginEditing上将其删除。
2. 设置textView边框宽度，边框颜色和背景颜色以使其可见。

   class ViewController: UIViewController, UITextViewDelegate {
   
   ...
   
   @IBAction func showAlert(sender: AnyObject) {
       let alertController = UIAlertController(title: "Hello, I'm alert! \n\n\n\n\n\n\n", message: "", preferredStyle: .Alert)
   
       let rect        = CGRectMake(15, 50, 240, 150.0)
       let textView    = UITextView(frame: rect)
   
       textView.font               = UIFont(name: "Helvetica", size: 15)
       textView.textColor          = UIColor.lightGrayColor()
       textView.backgroundColor    = UIColor.whiteColor()
       textView.layer.borderColor  = UIColor.lightGrayColor().CGColor
       textView.layer.borderWidth  = 1.0
       textView.text               = "Enter message here"
       textView.delegate           = self
   
       alertController.view.addSubview(textView)
   
       let cancel = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil)
       let action = UIAlertAction(title: "Ok", style: .Default, handler: { action in
   
           let msg = (textView.textColor == UIColor.lightGrayColor()) ? "" : textView.text
   
           print(msg)
   
       })
       alertController.addAction(cancel)
       alertController.addAction(action)
   
       self.presentViewController(alertController, animated: true, completion: {})
   
   }
   
   func textViewDidBeginEditing(textView: UITextView) {
       if textView.textColor == UIColor.lightGrayColor(){
           textView.text = ""
           textView.textColor = UIColor.darkGrayColor()
       }
   }
   }

Answer 3

以下代码适用于UITextView中的Multiline UIAlertController，写于Swift 4

    let alert = UIAlertController(title: "Enter your summary", message: "\n\n\n\n\n\n\n\n", preferredStyle: .alert)
    alert.view.autoresizesSubviews = true

    let textView = UITextView(frame: CGRect.zero)
    textView.translatesAutoresizingMaskIntoConstraints = false

    let leadConstraint = NSLayoutConstraint(item: alert.view, attribute: .leading, relatedBy: .equal, toItem: textView, attribute: .leading, multiplier: 1.0, constant: -8.0)
    let trailConstraint = NSLayoutConstraint(item: alert.view, attribute: .trailing, relatedBy: .equal, toItem: textView, attribute: .trailing, multiplier: 1.0, constant: 8.0)

    let topConstraint = NSLayoutConstraint(item: alert.view, attribute: .top, relatedBy: .equal, toItem: textView, attribute: .top, multiplier: 1.0, constant: -64.0)
    let bottomConstraint = NSLayoutConstraint(item: alert.view, attribute: .bottom, relatedBy: .equal, toItem: textView, attribute: .bottom, multiplier: 1.0, constant: 64.0)
    alert.view.addSubview(textView)
    NSLayoutConstraint.activate([leadConstraint, trailConstraint, topConstraint, bottomConstraint])
    alert.addAction(UIAlertAction(title: "Done", style: .default, handler: { action in
        print("\(String(describing: textView.text))")
    }))
    present(alert, animated: true)

Answer 4

您无法在UIAlertController中创建多行textView。你必须为此创建自己的UIAlertController。