当屏幕上出现视图时，如何使键盘将视图向上推？Xcode Swift

Question

所以我有一个带有文本字段的视图，但文本字段在底部。当我单击键盘时，它会弹出并覆盖文本字段，这是我的问题。我想知道当键盘出现时是否有可能将其余视图向上推？

Answer 1

您可以注册视图控制器，以便在即将显示键盘时得到通知，然后向上推视图。

class ViewController: UIViewController {

var keyboardAdjusted = false
var lastKeyboardOffset: CGFloat = 0.0

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
}

override func viewDidDisappear(animated: Bool) {
    super.viewDidDisappear(animated)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}

func keyboardWillShow(notification: NSNotification) {
    if keyboardAdjusted == false {
        lastKeyboardOffset = getKeyboardHeight(notification)
        view.frame.origin.y -= lastKeyboardOffset
        keyboardAdjusted = true
    }
}

func keyboardWillHide(notification: NSNotification) {
    if keyboardAdjusted == true {
        view.frame.origin.y += lastKeyboardOffset
        keyboardAdjusted = false
    }
}

func getKeyboardHeight(notification: NSNotification) -> CGFloat {
    let userInfo = notification.userInfo
    let keyboardSize = userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue
    return keyboardSize.CGRectValue().height
}

}