IOS UITableView中UITextField 弹出键盘时，界面上移

IOS 中键盘遮挡住UITextField的输入框，导致用户体验不好，一直是IOS的难点所在。

自学IOS时间不长，对于这个问题，如下是我的方法，仅供参考。

如果UITextField位于屏幕下方，键盘弹出时会挡住UITextField，建议将UITextField放入UIScrollview或UITableView中。

废话不多说，直接上代码

override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)

//add notification for keyboard did change frame
NSNotificationCenter.defaultCenter().addObserver(self, selector: "didChangeKeyboardFrame:", name: UIKeyboardDidChangeFrameNotification, object: nil)

//add notification for keyboard did hide
NSNotificationCenter.defaultCenter().addObserver(self, selector: "didHideKeyboard:", name: UIKeyboardDidHideNotification, object: nil)
}

override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)

//remove keyboard observer
NSNotificationCenter.defaultCenter().removeObserver(self)
}

func didChangeKeyboardFrame(notification: NSNotification) {
let rect = notification.userInfo![UIKeyboardFrameEndUserInfoKey]!.CGRectValue
let height = rect.size.height
var insets = self.tableView.contentInset
insets.bottom = height
self.tableView.contentInset = insets
insets = self.tableView.scrollIndicatorInsets
insets.bottom = height
self.tableView.scrollIndicatorInsets = insets
}

func didHideKeyboard(notification: NSNotification) {
var insets = self.tableView.contentInset
insets.bottom = 0.0
self.tableView.contentInset = insets
insets = self.tableView.scrollIndicatorInsets
insets.bottom = 0.0
self.tableView.scrollIndicatorInsets = insets
}

以上代码的tableView可以换成自己的scrollView。

UIScrollView contentInset : 视图在scrollView中的位置

UIScrollView scrollIndicatorInsets : 指定滚动条在scrollerView中的位置