如何在编辑文本后重置 tableview 的高度
How do I reset tableview's height after editing text
您好，我正在尝试在编辑文本后重置 tableview 的高度..
第 1 步。选中输入文本视图
第 2 步。在 1 行上输入评论消息..（例如 2 行、3 行..）
第 3 步。点击“发送”按钮
第 4 步。重置 UI
我的问题是..当我将评论输入为 1 行时...它工作正常..
但我确实输入了 2 行或更多行的评论...然后 tableview 的高度没有重置...
你能帮帮我吗？
import UIKit
import Parse
var commentUUID = [String]()
var commentOwner = [String]()
class CommentViewController: UIViewController, UITextViewDelegate, UITableViewDelegate, UITableViewDataSource{
//UI Objects
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var commentTextView: UITextView!
@IBOutlet weak var sendButton: UIButton!
@IBOutlet weak var bottomConstraint: NSLayoutConstraint!
var refresher = UIRefreshControl()
//values for reseting UI to default
var tableViewHeight : CGFloat = 0
var commentY : CGFloat = 0
var commentHeight : CGFloat = 0
var tableDiff : CGFloat = 0
//arryas to hold server data
var usernameArray = [String]()
var profileArray = [PFFile]()
var commentArray = [String]()
var dateArray = [NSDate?]()
//variable to hold keyboard frame
var keyboard = CGRect()
//page size
var page : Int32 = 15
override func viewDidLoad() {
super.viewDidLoad()
tableView.backgroundColor = UIColor(red: 242.0 / 255.0, green: 242.0 / 255.0, blue: 242.0 / 255.0, alpha: 1)
//title at the top
self.navigationItem.title = "COMMENTS"
self.navigationItem.hidesBackButton = true
// let backButton = UIBarButtonItem(title: "back", style: .Plain, target: self, action: #selector(CommentViewController.back(_:)))
let backButton = UIBarButtonItem(image: UIImage(named: "backBtn"), style: .Plain, target: self, action: #selector(CommentViewController.back(_:)))
self.navigationItem.leftBarButtonItem=backButton
//swipe to go back
let backSwipe = UISwipeGestureRecognizer(target: self, action: #selector(CommentViewController.back(_:)))
backSwipe.direction=UISwipeGestureRecognizerDirection.Right
self.view.addGestureRecognizer(backSwipe)
// catch notification if the keyboard is shown or hidden
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(CommentViewController.keyboardWillShow(_:)), name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(CommentViewController.keyboardWillHide(_:)), name: UIKeyboardWillHideNotification, object: nil)
//disable button from the beginning
sendButton.enabled = false
loadComments()
//call function
alignment()
}
//func loading when keyboard is shown
func keyboardWillShow(notification : NSNotification){
//define keyboard frame size
keyboard = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey]!.CGRectValue)!
//move UI up
UIView.animateWithDuration(0.4){ () -> Void in
self.bottomConstraint.constant = self.keyboard.height + 4
self.tableDiff = self.tableView.frame.size.height
}
}
//func loading when keyboard is hidden
func keyboardWillHide(notification : NSNotification){
//move UI down
UIView.animateWithDuration(0.4){() -> Void in
}
}
//alignment function
func alignment(){
tableView.rowHeight = UITableViewAutomaticDimension
tableView.estimatedRowHeight = 160.0
//set CommentTextView Style
commentTextView.layer.cornerRadius = commentTextView.frame.size.width / 50
//delegates
commentTextView.delegate = self
tableView.delegate = self
tableView.dataSource = self
//assign reseting values
tableViewHeight = tableView.frame.size.height
commentHeight = commentTextView.frame.size.height
commentY = commentTextView.frame.origin.y
}
//while writing something
func textViewDidChange(textView: UITextView) {
//disable button if entered no text
let spacing = NSCharacterSet.whitespaceAndNewlineCharacterSet()
//It shown when user entered type
if !commentTextView.text.stringByTrimmingCharactersInSet(spacing).isEmpty{
sendButton.enabled = true
}else {
sendButton.enabled = false
}
// + paragraph
if textView.contentSize.height > textView.frame.size.height && textView.frame.height < 130{
//find difference to add
let difference = textView.contentSize.height - textView.frame.size.height
self.tableDiff = difference
//redefine frame of commentText
textView.frame.origin.y = textView.frame.origin.y - difference
textView.frame.size.height = textView.contentSize.height
//move up tableView
if textView.contentSize.height + keyboard.height + commentY >= tableView.frame.size.height {
tableView.frame.size.height = tableView.frame.size.height - difference
}
}
// - parapraph
else if textView.contentSize.height < textView.frame.size.height {
//find difference to deduct
let difference = textView.frame.size.height - textView.contentSize.height
self.tableDiff = difference
//redefine frame of commentText
textView.frame.origin.y = textView.frame.origin.y + difference
textView.frame.size.height = textView.contentSize.height
//move down tableview
if textView.contentSize.height + keyboard.height + commentY > tableView.frame.size.height {
tableView.frame.size.height = tableView.frame.size.height + difference
}
}
}
//点击发送按钮
@IBAction func sendButtonTapped（发件人：AnyObject）{
print("send tapped")
//STEP1. Add row in tableView
usernameArray.append(PFUser.currentUser()!.username!)
profileArray.append(PFUser.currentUser()?.objectForKey("profileImg") as! PFFile)
dateArray.append(NSDate())
commentArray.append(commentTextView.text.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()))
tableView.reloadData()
//STEP2. Send comment to server
let commentObj = PFObject(className: "comments")
commentObj["to"] = commentUUID.last
commentObj["username"] = PFUser.currentUser()?.username
commentObj["profileImg"] = PFUser.currentUser()?.valueForKey("profileImg")
commentObj["comment"] = commentTextView.text.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
commentObj.saveEventually()
//Scroll to bottom
self.tableView.scrollToRowAtIndexPath(NSIndexPath(forItem: commentArray.count - 1, inSection: 0), atScrollPosition: UITableViewScrollPosition.Bottom, animated: false)
//STEP 3. Reset UI
sendButton.enabled = false
commentTextView.text = ""
commentTextView.frame.size.height = commentHeight
commentTextView.frame.origin.y = sendButton.frame.origin.y
//TableView Reset....Is Not working.
tableView.frame.size.height = tableView.frame.size.height
}
您似乎在使用自动布局，因此您应该更新约束而不是更新 tableView.frame。为您的 tableView heightConstraint 创建一个 IBOutlet，然后为其设置更新后的高度。
IBOutlet weak var tableHeightConstraint: NSLayoutConstraint!
//calculate the height and update the constant
tableHeightConstraint.constant = updatedTableHeight
另外，从您的代码来看，您似乎只是在更新 tableView.frame.height 本身。您应该计算值并设置为上述约束。
您好，我正在尝试在编辑文本后重置 tableview 的高度..
第 1 步。选中输入文本视图
第 2 步。在 1 行上输入评论消息..（例如 2 行、3 行..）
第 3 步。点击“发送”按钮
第 4 步。重置 UI
我的问题是..当我将评论输入为 1 行时...它工作正常..
但我确实输入了 2 行或更多行的评论...然后 tableview 的高度没有重置...
你能帮帮我吗？
import UIKit
import Parse
var commentUUID = [String]()
var commentOwner = [String]()
class CommentViewController: UIViewController, UITextViewDelegate, UITableViewDelegate, UITableViewDataSource{
//UI Objects
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var commentTextView: UITextView!
@IBOutlet weak var sendButton: UIButton!
@IBOutlet weak var bottomConstraint: NSLayoutConstraint!
var refresher = UIRefreshControl()
//values for reseting UI to default
var tableViewHeight : CGFloat = 0
var commentY : CGFloat = 0
var commentHeight : CGFloat = 0
var tableDiff : CGFloat = 0
//arryas to hold server data
var usernameArray = [String]()
var profileArray = [PFFile]()
var commentArray = [String]()
var dateArray = [NSDate?]()
//variable to hold keyboard frame
var keyboard = CGRect()
//page size
var page : Int32 = 15
override func viewDidLoad() {
super.viewDidLoad()
tableView.backgroundColor = UIColor(red: 242.0 / 255.0, green: 242.0 / 255.0, blue: 242.0 / 255.0, alpha: 1)
//title at the top
self.navigationItem.title = "COMMENTS"
self.navigationItem.hidesBackButton = true
// let backButton = UIBarButtonItem(title: "back", style: .Plain, target: self, action: #selector(CommentViewController.back(_:)))
let backButton = UIBarButtonItem(image: UIImage(named: "backBtn"), style: .Plain, target: self, action: #selector(CommentViewController.back(_:)))
self.navigationItem.leftBarButtonItem=backButton
//swipe to go back
let backSwipe = UISwipeGestureRecognizer(target: self, action: #selector(CommentViewController.back(_:)))
backSwipe.direction=UISwipeGestureRecognizerDirection.Right
self.view.addGestureRecognizer(backSwipe)
// catch notification if the keyboard is shown or hidden
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(CommentViewController.keyboardWillShow(_:)), name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(CommentViewController.keyboardWillHide(_:)), name: UIKeyboardWillHideNotification, object: nil)
//disable button from the beginning
sendButton.enabled = false
loadComments()
//call function
alignment()
}
//func loading when keyboard is shown
func keyboardWillShow(notification : NSNotification){
//define keyboard frame size
keyboard = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey]!.CGRectValue)!
//move UI up
UIView.animateWithDuration(0.4){ () -> Void in
self.bottomConstraint.constant = self.keyboard.height + 4
self.tableDiff = self.tableView.frame.size.height
}
}
//func loading when keyboard is hidden
func keyboardWillHide(notification : NSNotification){
//move UI down
UIView.animateWithDuration(0.4){() -> Void in
}
}
//alignment function
func alignment(){
tableView.rowHeight = UITableViewAutomaticDimension
tableView.estimatedRowHeight = 160.0
//set CommentTextView Style
commentTextView.layer.cornerRadius = commentTextView.frame.size.width / 50
//delegates
commentTextView.delegate = self
tableView.delegate = self
tableView.dataSource = self
//assign reseting values
tableViewHeight = tableView.frame.size.height
commentHeight = commentTextView.frame.size.height
commentY = commentTextView.frame.origin.y
}
//while writing something
func textViewDidChange(textView: UITextView) {
//disable button if entered no text
let spacing = NSCharacterSet.whitespaceAndNewlineCharacterSet()
//It shown when user entered type
if !commentTextView.text.stringByTrimmingCharactersInSet(spacing).isEmpty{
sendButton.enabled = true
}else {
sendButton.enabled = false
}
// + paragraph
if textView.contentSize.height > textView.frame.size.height && textView.frame.height < 130{
//find difference to add
let difference = textView.contentSize.height - textView.frame.size.height
self.tableDiff = difference
//redefine frame of commentText
textView.frame.origin.y = textView.frame.origin.y - difference
textView.frame.size.height = textView.contentSize.height
//move up tableView
if textView.contentSize.height + keyboard.height + commentY >= tableView.frame.size.height {
tableView.frame.size.height = tableView.frame.size.height - difference
}
}
// - parapraph
else if textView.contentSize.height < textView.frame.size.height {
//find difference to deduct
let difference = textView.frame.size.height - textView.contentSize.height
self.tableDiff = difference
//redefine frame of commentText
textView.frame.origin.y = textView.frame.origin.y + difference
textView.frame.size.height = textView.contentSize.height
//move down tableview
if textView.contentSize.height + keyboard.height + commentY > tableView.frame.size.height {
tableView.frame.size.height = tableView.frame.size.height + difference
}
}
}
//点击发送按钮 @IBAction func sendButtonTapped（发件人：AnyObject）{
print("send tapped")
//STEP1. Add row in tableView
usernameArray.append(PFUser.currentUser()!.username!)
profileArray.append(PFUser.currentUser()?.objectForKey("profileImg") as! PFFile)
dateArray.append(NSDate())
commentArray.append(commentTextView.text.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()))
tableView.reloadData()
//STEP2. Send comment to server
let commentObj = PFObject(className: "comments")
commentObj["to"] = commentUUID.last
commentObj["username"] = PFUser.currentUser()?.username
commentObj["profileImg"] = PFUser.currentUser()?.valueForKey("profileImg")
commentObj["comment"] = commentTextView.text.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
commentObj.saveEventually()
//Scroll to bottom
self.tableView.scrollToRowAtIndexPath(NSIndexPath(forItem: commentArray.count - 1, inSection: 0), atScrollPosition: UITableViewScrollPosition.Bottom, animated: false)
//STEP 3. Reset UI
sendButton.enabled = false
commentTextView.text = ""
commentTextView.frame.size.height = commentHeight
commentTextView.frame.origin.y = sendButton.frame.origin.y
//TableView Reset....Is Not working.
tableView.frame.size.height = tableView.frame.size.height
}
您似乎在使用自动布局，因此您应该更新约束而不是更新 tableView.frame。为您的 tableView heightConstraint 创建一个 IBOutlet，然后为其设置更新后的高度。
IBOutlet weak var tableHeightConstraint: NSLayoutConstraint!
//calculate the height and update the constant
tableHeightConstraint.constant = updatedTableHeight
另外，从您的代码来看，您似乎只是在更新 tableView.frame.height 本身。您应该计算值并设置为上述约束。