获取文本字段和键盘之间的高度

Question

我有一个包含表单的视图控制器，我想获取文本字段的底部 Y 位置和键盘顶部 Y 位置之间的高度(距离(。 我做了一个说明我的意思： 插图 我尝试过但不起作用的代码：

let textFieldBottomY = myTextField.frame.origin.y + myTextField.frame.size.height
let keyboardTopY = self.view.frame.height - keyboardHeight
distanceHeight = keyboardTopY - textFieldBottomY

上面的函数从NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: .UIKeyboardWillShow, object: nil)调用keyboardHeight来自此函数：

if let keyboardFrame: NSValue = notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue {
let keyboardSize = keyboardFrame.cgRectValue.height
}

我想实现的事情是在TextField和Keyboard之间画一个UIView我得到的distanceHeight值不正确，高度超过键盘。

感谢您的帮助。

Answer 1

如果keyboardWillShow则设置keyboardHeight= 0

，如果
keyboardWillHide则KeyboardWillChangeFrame    keyboardHeight=keyboardFrameEnd.height

    keyboardHeight= 0

其余代码工作正常
假设您的文本字段是 self.view 的子视图

let textFieldBottomY = tfAny.frame.origin.y + tfAny.frame.size.height
let keyboardTopY = self.view.frame.height - keyboardHeight    
let distanceHeight = abs(keyboardTopY - textFieldBottomY)

否则如果在滚动视图中

let textFieldBottomPoint = CGPoint(x: 0, y: tfAny.frame.origin.y + tfAny.frame.height)
let textFieldBottomY = scrollView.convert(textFieldBottomPoint, to: view).y
let keyboardTopY = self.view.frame.height - keyboardHeight
let distanceHeight = abs(keyboardTopY - textFieldBottomY)