我有一个Swift文件,我正在尝试创建一个自定义类,以处理一个页面上多个文本视图的占位符。我更喜欢单独的课程,因为我认为它的清洁剂可以处理多个视图。问题是,当这些事件发生时,函数 textViewDideDediting 和 textViewDidbeginediting 不会被调用。
我已经通过将延迟设置为代表成功成功地工作了,但是我看不出如何使用多个UitextViews做到这一点。
这是我的代码:
import UIKit
class PostPage: UIViewController, UITextViewDelegate {
@IBOutlet weak var eventDescription: UITextView!
@IBOutlet weak var eventTitle: UITextView!
var placeholderShowing = true
override func viewDidLoad() {
super.viewDidLoad()
// Add a placeholder for the text
let ph_descr = PlaceHolderHandler(placeholderText: "Description", textBox: eventDescription)
eventDescription.delegate = ph_descr
let ph_title = PlaceHolderHandler(placeholderText: "Title", textBox: eventTitle)
eventTitle.delegate = ph_title
}
}
class PlaceHolderHandler: NSObject, UITextViewDelegate {
var placeholderShowing = true
var placeholderText = ""
required init(placeholderText: String, textBox: UITextView) {
super.init()
self.placeholderText = placeholderText
textBox.text = placeholderText
textBox.textColor = UIColor.lightGray
}
// MARK:- UITextViewDelegates
public func textViewDidBeginEditing(_ textView: UITextView) {
if self.placeholderShowing {
textView.text = ""
textView.textColor = UIColor.black
self.placeholderShowing = false
}
}
public func textViewDidEndEditing(_ textView: UITextView) {
if textView.text == "" {
textView.text = "Description"
textView.textColor = UIColor.lightGray
self.placeholderShowing = true
}
}
}
当我选择任何一个UITEXTVIEWS时,我都希望调用相应的函数,并进行相应的调整。
您需要保留phDescr
和phTitle
,就像您的代码一样,它们是本地变量,因此获得viewDidLoad
import UIKit
class PostPage: UIViewController, UITextViewDelegate {
@IBOutlet weak var eventDescription: UITextView!
@IBOutlet weak var eventTitle: UITextView!
var placeholderShowing = true
var phDescr, phTitle:PlaceHolderHandler!
override func viewDidLoad() {
super.viewDidLoad()
// Add a placeholder for the text
phDescr = PlaceHolderHandler(placeholderText: "Description", textBox: eventDescription)
eventDescription.delegate = phDescr
phTitle = PlaceHolderHandler(placeholderText: "Title", textBox: eventTitle)
eventTitle.delegate = phTitle
}
}
还使用骆驼命名变量
我通过将延迟设置为代表,成功地工作了,但是我看不出如何使用多个UITEXTVIEW
来做到这一点
OFF课程您可以将同时设置为PostPage
的委托,并且知道哪个是一个完整的使用
func textViewDidBeginEditing(_ textView: UITextView) {
if textView == eventDescription {
}
else { // eventTitle
}
}