ios - 根据键盘是否可见更改 TextView 的框架

Question

我正在使用观察器来确定键盘是否被隐藏。键盘应该在 View 加载后立即自动显示，这应该触发调整 View 的观察者。当 View 加载时，键盘出现，但仍然有部分 TextView 隐藏在键盘后面，一旦您隐藏键盘并再次显示它，它将正确调整 TextView 的大小。

在 viewDidLoad 中我添加了观察者

let notificationCenter = NotificationCenter.default
    notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardDidHideNotification, object: nil)
    notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardDidHideNotification, object: nil)

我的textview成为viewDidAppear中的第一响应者

override func viewDidAppear(_ animated: Bool) {

    noteTextView.becomeFirstResponder()

}

最终 View 得到调整

@objc func adjustForKeyboard(notification: Notification) {
    let userInfo = notification.userInfo!

    let keyboardScreenEndFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
    let keyboardViewEndFrame = view.convert(keyboardScreenEndFrame, from: noteTextView.window)

    if notification.name == UIResponder.keyboardWillHideNotification {
        noteTextView.contentInset = UIEdgeInsets.zero
    } else {
        noteTextView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardViewEndFrame.height, right: 0)
    }

    noteTextView.scrollIndicatorInsets = noteTextView.contentInset

    let selectedRange = noteTextView.selectedRange
    noteTextView.scrollRangeToVisible(selectedRange)
}

我该如何解决这个问题，以便它在第一时间正确显示？使用最新版本的 xcode。

隐藏键盘之前

隐藏键盘后可以看到textview隐藏在了它的后面

再次显示键盘后，textview 的大小被调整。

Answer 1

你复制了keyboardDidHideNotification

notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardDidHideNotification, object: nil)
notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardDidHideNotification, object: nil)

你还需要keyboardWillShowNotification

notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardDidHideNotification, object: nil) 
notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillShowNotification, object: nil)