在出现键盘时处理 tableView contentInset

Posted 2023-03-12

【中文标题】在出现键盘时处理 tableView contentInset

【英文标题】：Handle tableView contentInset while keyboard is presented

【发布时间】：2015-12-30 14:44:38

【问题描述】：

我正在构建一个示例，我可以在其中发布 cmets，我每次发布时使用 tableView 添加一个单元格。它主要处理但我想发表评论时遇到一个问题，tableview底部与键盘高度相同但为空，如果将其设置为零，视图将向下移动然后推到顶部，那是因为我当我点击 textview 写文本时移动整个视图。

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设置了底部（内容插入）= 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()

【参考方案1】：

这种情况下最好改变tableview的frame。

您可以将约束的实例保留在commentView的底部和底部布局指南之间。

@IBOutlet weak var commentViewBottom: NSLayoutConstraint!

然后在需要的时候改变约束的常量。

    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)