ios - 在出现键盘时处理 tableView contentInset

Question

我正在构建一个示例，我可以在其中发表评论，我每次发表评论时都使用 tableView 添加一个单元格。它主要被处理但是当我想发表评论时我遇到了一个问题，tableview 底部与键盘高度相同但为空，如果将它放置为零， View 将向下移动然后推到顶部，那是因为我是当我点击 textview 来写文本时移动整个 View 。

这是 tableView 下空白区域的预览(键盘高度为插图):Preview of image on Google Drive

另一张图片，看看我是否在键盘打开时使底部(内容插图)= 0:Preview of second image on Google Drive

 func keyboardWillShow(sender:NSNotification){

        let userInfo: [NSObject : AnyObject] = sender.userInfo!
        keyboardSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
        var contentInsets = UIEdgeInsets()

        if wasEmoj == true {
            if (UIInterfaceOrientationIsPortrait(UIApplication.sharedApplication().statusBarOrientation)) {
                contentInsets = UIEdgeInsetsMake(257.0, 0.0, (self.keyboardSize.height), 0.0);
            } else {
                contentInsets = UIEdgeInsetsMake(257.0, 0.0, (self.keyboardSize.width), 0.0);
            }
            self.mytableView.contentInset = contentInsets;
            self.mytableView.scrollIndicatorInsets = contentInsets
        }else {
        if (UIInterfaceOrientationIsPortrait(UIApplication.sharedApplication().statusBarOrientation)) {
            contentInsets = UIEdgeInsetsMake(215.0, 0.0,(self.keyboardSize.height), 0.0);
        } else {
            contentInsets = UIEdgeInsetsMake(215.0, 0.0, (self.keyboardSize.width), 0.0);
        }

            self.mytableView.contentInset = contentInsets;
            self.mytableView.scrollIndicatorInsets = contentInsets

        }
}

func textViewDidBeginEditing(textView: UITextView) {

    self.animateTextField(commentText, up: true, movementDistance: -215, duration: 0.3)

}
///- animate the view up or down to adapt with keyboard
func animateTextField (textField:UITextView,up:Bool,movementDistance:Int,duration:NSTimeInterval){

    let movement : Int = (up ? movementDistance : -movementDistance);
    UIView.beginAnimations("animateTextField", context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    if up == true {
        UIView.setAnimationDuration(0.38)
    }else {
        UIView.setAnimationDuration(0.3)
    }
    self.view.frame = CGRectOffset(self.view.frame, 0, CGFloat(movement))
    UIView.commitAnimations()


}

Answer 1

在这种情况下，最好更改表格 View 的框架。

您可以保留 commentView 底部和底部布局指南之间的约束实例。

@IBOutlet weak var commentViewBottom: NSLayoutConstraint!

然后在需要时更改约束的常量。

    func keyboardWillShow(sender:NSNotification){

        if let dic = sender.userInfo {
            if let keyboardFrame = dic[UIKeyboardFrameEndUserInfoKey]?.CGRectValue {
                if let duration = dic[UIKeyboardAnimationDurationUserInfoKey]?.doubleValue {
                    commentViewBottom.constant = -keyboardFrame.height

                    UIView.animateWithDuration(duration, delay: 0.0, usingSpringWithDamping: 1.0, initialSpringVelocity: 0.5, options: .CurveLinear, animations: { () -> Void in
                        self.view.layoutIfNeeded()
                        }, completion: nil)
                }
            }
        }
    }


    func keyboardWillHide(sender: NSNotification) {
        if let dic = sender.userInfo, let duration = dic[UIKeyboardAnimationDurationUserInfoKey]?.doubleValue {
                commentViewBottom.constant = 0

                UIView.animateWithDuration(duration, delay: 0.0, usingSpringWithDamping: 1.0, initialSpringVelocity: 0.5, options: .CurveLinear, animations: { () -> Void in
                    self.view.layoutIfNeeded()
                    }, completion: nil)
        }
}