ios - 当键盘盖住它时向上移动文本字段

Question

我对 Objective C 不是很熟悉，想知道 Swift 中是否有解决这个问题的方法。

这是我正在玩的一个非常简单的 SingleView 应用程序。 UIView 继承自 UIControl。

我没有 UIScrollView，我不能把整个 View 向上移动吗？我相信键盘与此无关。

Answer 1

Apple 的推荐用 Swift 重新编码。

确保您的控件位于 ScrollView 上，并注意选择器字符串中的冒号。我使用变量 (activeField) 来指示事件文本字段。

var activeField: UITextField?

@IBAction func editingBegan(sender: UITextField) {
    activeField = sender
}

 override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)
    let center = NSNotificationCenter.defaultCenter()
    center.addObserver(self, selector: "keyboardOnScreen:", name: UIKeyboardDidShowNotification, object: nil)
    center.addObserver(self, selector: "keyboardOffScreen:", name: UIKeyboardDidHideNotification, object: nil)

}

func keyboardOnScreen(notification: NSNotification){
    let info: NSDictionary  = notification.userInfo!
    let kbSize = info.valueForKey(UIKeyboardFrameEndUserInfoKey)?.CGRectValue().size
    let contentInsets:UIEdgeInsets  = UIEdgeInsetsMake(0.0, 0.0, kbSize!.height, 0.0)
    scrollView.contentInset = contentInsets
    scrollView.scrollIndicatorInsets = contentInsets
    var aRect: CGRect = self.view.frame
    aRect.size.height -= kbSize!.height
    //you may not need to scroll, see if the active field is already visible
    if (!CGRectContainsPoint(aRect, activeField!.frame.origin) ) {
        let scrollPoint:CGPoint = CGPointMake(0.0, activeField!.frame.origin.y - kbSize!.height)
        scrollView.setContentOffset(scrollPoint, animated: true)
    }

}


func keyboardOffScreen(notification: NSNotification){
    let contentInsets:UIEdgeInsets = UIEdgeInsetsZero
    scrollView.contentInset = contentInsets
    scrollView.scrollIndicatorInsets = contentInsets
}