完成按钮崩溃应用程序

Question

我想要一种在输入UITextField时关闭键盘的方法。我在谷歌上查了一下，在Medium上找到了这个：

https://medium.com/@KaushElsewhere/how-to-dismiss-keyboard-in-a-view-controller-of-ios-3b1bfe973ad1

每次我按下完成按钮时，应用程序都会崩溃。任何帮助将不胜感激。

法典：

override func viewDidLoad() {
super.viewDidLoad()
//init toolbar
let toolbar:UIToolbar = UIToolbar(frame: CGRect(x: 0, y: 0,  width: self.view.frame.size.width, height: 30))
//create left side empty space so that done button set on right side
let flexSpace = UIBarButtonItem(barButtonSystemItem:    .flexibleSpace, target: nil, action: nil)
let doneBtn: UIBarButtonItem = UIBarButtonItem(title: “Done”, style: .done, target: self, action: Selector(“doneButtonAction”))
toolbar.setItems([flexSpace, doneBtn], animated: false)
toolbar.sizeToFit()
//setting toolbar as inputAccessoryView
self.textField1.inputAccessoryView = toolbar
self.textField2.inputAccessoryView = toolbar
}
func doneButtonAction() {
self.view.endEditing(true)
}

Answer 1

您需要将@objc添加到doneButtonAction函数中，因为这是它崩溃的原因。并使用 #selector 而不是选择器。

override func viewDidLoad() {
super.viewDidLoad()
//init toolbar
let toolbar:UIToolbar = UIToolbar(frame: CGRect(x: 0, y: 0,  width: 
self.view.frame.size.width, height: 30))
//create left side empty space so that done button set on right side
let flexSpace = UIBarButtonItem(barButtonSystemItem:    .flexibleSpace, target: nil, action: nil)
let doneBtn: UIBarButtonItem = UIBarButtonItem(title: "Done", style: .done, target: self, action: #selector(doneButtonAction))
toolbar.setItems([flexSpace, doneBtn], animated: false)
toolbar.sizeToFit()
//setting toolbar as inputAccessoryView
self.textField1.inputAccessoryView = toolbar
self.textField2.inputAccessoryView = toolbar
}
@objc func doneButtonAction() {
self.view.endEditing(true)
}