arrays - 输入新值时复制表的最后一行
问题描述
我的应用程序中有一个聊天功能。该页面将现有数据加载为名为 hhmessages 的数组。对话中的最后一条消息是“欢迎”，当我输入新文本“谢谢”并按 Enter 键时，表格会自动再次显示“欢迎”而不是“谢谢”。如果它退出页面并返回，它现在会显示“谢谢”作为最后一条消息。它在后端工作，只是即时更新在输入时没有显示 UITableView 中的值。
这适用于 iPhone 应用程序。更新以显示完整代码 - 现在反向已被删除，新条目显示为空白。
import UIKit
import Foundation
extension String {
// Calculeta the hight string Function
func calculateTextFrameRect(
objectsInPlaceHeight: CGFloat,
objectsInPlaceWidth: CGFloat,
fontSize: CGFloat,
fontWeight: CGFloat) -> CGSize
{
let bounding = CGSize(width: UIScreen.main.bounds.width - objectsInPlaceWidth, height: .infinity)
let rect = NSString(string: self).boundingRect(
with: bounding,
options: NSStringDrawingOptions.usesFontLeading.union(NSStringDrawingOptions.usesLineFragmentOrigin),
attributes: [NSAttributedStringKey.font: UIFont.systemFont(ofSize: fontSize, weight: UIFont.Weight(rawValue: fontWeight))],
context: nil)
return CGSize(width: UIScreen.main.bounds.width, height: rect.height + objectsInPlaceHeight )
}
}
// Messages for test
let frame = CGRect(origin: .zero, size: CGSize.init(width: 375, height: 559))
class Message {
let message: String
var incoming: [Int]
let image: UIImage
var avas = UIImage()
init(message: String, image: UIImage, incoming: Int, avas: UIImage) {
self.message = message
self.image = image
self.incoming = [incoming]
self.avas = avas
}
}
class ConversationViewController: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate, UITableViewDelegate, UITableViewDataSource, UITextViewDelegate {
//var user = NSDictionary()
var messages = NSDictionary()
//var guest = NSDictionary()
@IBOutlet var senderLbl: UILabel!
@IBOutlet var senderageLbl: UILabel!
@IBOutlet var senderraceLbl: UILabel!
@IBOutlet var sendergenderLbl: UILabel!
@IBOutlet var sendercityLbl: UILabel!
@IBOutlet var senderstateLbl: UILabel!
// @IBOutlet var tableView: UITableView!
var hhmessages = [AnyObject]()
//var messages: [Message] = []
var pictures = [UIImage]()
var avas = [UIImage]()
var avaURL = [String]()
var isLoading = false
var skip = 0
var limit = 50
var images = [UIImage]()
var incoming: [Int] = []
var comments = [String]()
var ids = [String]()
//var isSent: String = ""
var isPictureSelected = false
//var currentUser_ava = [Any]()
@IBOutlet var pictureImg: UIImageView!
@IBOutlet var avaImg: UIImageView!
@IBOutlet var viewprofile_btn: UIButton!
@IBOutlet var imgprofile_btn: UIButton!
@IBOutlet var replyTxt: UITextView!
//var replyTxt:UITextView!
@IBOutlet var replyTxt_height: NSLayoutConstraint!
@IBOutlet var replyTxt_bottom: NSLayoutConstraint!
@IBOutlet var picSelect: UIButton!
@IBOutlet var replyBtn: UIButton!
var puuid = String()
var imageSelected = false
var coolIndicator: UIActivityIndicatorView!
var commentsTextView_bottom_identity = CGFloat()
@IBOutlet var tableView: UITableView!
// Table View here + basic configuration
override func viewDidLoad() {
//self.tabBarController?.tabBar.isHidden = true
super.viewDidLoad()
tableView.transform = CGAffineTransform(rotationAngle: -(CGFloat)(Double.pi));
// dynamic cell height
tableView.dataSource = self
tableView.delegate = self
tableView.rowHeight = UITableViewAutomaticDimension
tableView.estimatedRowHeight = 200
loadPosts()
replyTxt.layer.cornerRadius = replyTxt.bounds.width / 50
replyTxt.backgroundColor = UIColor.clear
replyTxt.layer.borderColor = UIColor.gray.cgColor
replyTxt.layer.borderWidth = 1.0
let username = messages["sender"] as? String
self.navigationItem.title = username
}
// pre last func
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
// remove observers of notification when the viewController is left
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
// exec-d once notification is caught -> KeyboardWillShow
@objc func keyboardWillShow(_ notification: Notification) {
// getting the size of the keyboard
if let keyboard_size = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
// increasing the bottom constraint by the keyboard's height
replyTxt_bottom.constant += keyboard_size.height
}
// updating the layout with animation
UIView.animate(withDuration: 0.3) {
self.view.layoutIfNeeded()
}
}
// exec-d once notification is caught -> KeyboardWillHide
@objc func keyboardWillHide() {
// updating the layout with animation
UIView.animate(withDuration: 0.3) {
self.view.layoutIfNeeded()
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
//replyTxt().resignFirstResponder()
self.view.endEditing(false)
}
// TABLEVIEW
// Number os cells
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return hhmessages.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let colorSmoothGray = UIColor(red: 229/255, green: 229/255, blue: 234/255, alpha: 1)
let colorBrandBlue = UIColor(red: 148 / 255, green: 33 / 255, blue: 147 / 255, alpha: 1)
let pictureURL = hhmessages[indexPath.row]["uploadpath"] as? String
print("test 1", pictureURL)
// no picture in the post
if pictureURL == nil || pictureURL == "" {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! ConversationCell
cell.transform = CGAffineTransform(rotationAngle: CGFloat(Double.pi))
// shortcuts
let hhpost = hhmessages[indexPath.row]
let text = hhpost["messagetext"] as? String
cell.messageLbl.text = text
cell.messageLbl.textAlignment = .right
cell.messageLbl.backgroundColor = colorSmoothGray
cell.messageLbl.textColor = .black
cell.messageLbl.font = UIFont.preferredFont(forTextStyle: UIFontTextStyle.body)
cell.messageLbl.font?.withSize(25)
cell.messageLbl.clipsToBounds = true
cell.messageLbl.sizeToFit()
pictures.append(UIImage())
return cell
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "PicCell", for: indexPath) as! PicConversationCell
cell.transform = CGAffineTransform(rotationAngle: CGFloat(Double.pi))
let smimages = hhmessages[indexPath.row]["path"] as? UIImage
cell.smavaImg.image = smimages
for i in 0 ..< self.incoming.count {
// Confiture the constraints for cell
if self.incoming[indexPath.row] == 1 {
// Text
cell.messageLbl.textAlignment = .left
cell.messageLbl.backgroundColor = colorBrandBlue
cell.messageLbl.textColor = .white
cell.messageLbl.font = UIFont.preferredFont(forTextStyle: UIFontTextStyle.body)
cell.messageLbl.font?.withSize(25)
cell.messageLbl.clipsToBounds = true
// Constraints
cell.lefBubbleConstraint.isActive = true
cell.rightBubbleConstraint.isActive = false
if cell.postpictureImg.image == nil {
cell.postpictureImg.backgroundColor = .black
cell.postpictureImg.clipsToBounds = true
}
else {
cell.postpictureImg.backgroundColor = .black
cell.postpictureImg.clipsToBounds = true
}
}
else if self.incoming[indexPath.row] == 0 {
// Text
cell.messageLbl.textAlignment = .right
cell.messageLbl.backgroundColor = colorSmoothGray
cell.messageLbl.textColor = .black
cell.messageLbl.font = UIFont.preferredFont(forTextStyle: UIFontTextStyle.body)
cell.messageLbl.font?.withSize(25)
cell.messageLbl.clipsToBounds = true
// Constraints
cell.lefBubbleConstraint.isActive = false
cell.rightBubbleConstraint.isActive = true
if cell.postpictureImg.image == nil {
cell.postpictureImg.backgroundColor = .black
cell.postpictureImg.clipsToBounds = true
}
else {
cell.postpictureImg.backgroundColor = .black
cell.postpictureImg.clipsToBounds = true
}
}
if cell.lefBubbleConstraint.isActive == true {
cell.lefImageConstraint.isActive = true
cell.rightImageConstraint.isActive = false
} else {
cell.lefImageConstraint.isActive = false
cell.rightImageConstraint.isActive = true
}
let pictureString = hhmessages[indexPath.row]["uploadpath"] as! String
let pictureURL = URL(string: pictureString)!
// if there are still pictures to be loaded
if hhmessages.count != pictures.count {
URLSession(configuration: .default).dataTask(with: pictureURL) { (data, response, error) in
// downloaded
if let image = UIImage(data: data!) {
self.pictures.append(image)
DispatchQueue.main.async {
cell.postpictureImg.image = image
}
}
}.resume()
// cached picture
} else {
DispatchQueue.main.async {
cell.postpictureImg.image = self.pictures[indexPath.row]
}
}
}
return cell
}
}
// pre load func
override func viewDidAppear(_ animated: Bool) {
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
}
// func of loading posts from server
@objc func loadPosts() {
//isLoading = true
let me = user!["username"] as! String
let meid = user!["id"] as! String
print(meid)
print(me)
//print(username)
let uuid = messages["uuid"] as! String
print(uuid)
// accessing php file via url path
let url = URL(string: "http://localhost/message.php")!
// pass information to php file
let body = "username=\(me)&uuid=\(uuid)&recipient_id=\(meid)"
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.httpBody = body.data(using: String.Encoding.utf8)
tableView.transform = CGAffineTransform(rotationAngle: -(CGFloat)(Double.pi));
// launch session
URLSession.shared.dataTask(with: request) { (data, response, error) in
DispatchQueue.main.async {
// no error of accessing php file
// error occured
if error != nil {
Helper().showAlert(title: "Server Error", message: error!.localizedDescription, in: self)
//self.isLoading = false
return
}
do {
// access data - safe mode
guard let data = data else {
Helper().showAlert(title: "Data Error", message: error!.localizedDescription, in: self)
//self.isLoading = false
return
}
// getting content of $returnArray variable of php file
let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? NSDictionary
// accessing json data - safe mode
guard let posts = json?["messages"] as? [NSDictionary] else {
//self.isLoading = false
return
}
// assigning all successfully loaded posts to our Class Var - posts (after it got loaded successfully)
self.hhmessages = posts
self.tableView.reloadData()
// scroll to the latest index (latest cell -> bottom)
let indexPath = IndexPath(row: self.hhmessages.count - 1, section: 0)
self.tableView.scrollToRow(at: indexPath, at: .bottom, animated: true)
// self.isLoading = false
} catch {
Helper().showAlert(title: "JSON Error", message: error.localizedDescription, in: self)
//self.isLoading = false
return
}
}
}.resume()
}
@IBAction func viewprofile_clicked(_ sender: Any) {
// performSegue(withIdentifier: "guest2", sender: self.guest)
}
@IBAction func imgprofile_clicked(_ sender: Any) {
// performSegue(withIdentifier: "guest2", sender: self.guest)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "guest" {
if let destination = segue.destination as? GuestViewController {
destination.guest = messages
}
}
}
// function sending requset to PHP to uplaod a file
func uploadPost() {
// validating vars before sending to the server
guard let user_id = user?["id"] as? String, let username = user?["username"] as? String, let avaPath = user?["ava"] else {
// converting url string to the valid URL
if let url = URL(string: user?["ava"] as! String) {
// downloading all data from the URL
guard let data = try? Data(contentsOf: url) else {
return
}
// converting donwloaded data to the image
guard let image = UIImage(data: data) else {
return
}
// assigning image to the global var
let currentUser_ava = image
}
return
}
let user_id_int = Int(user_id)!
let messagetext = replyTxt.text.trimmingCharacters(in: .whitespacesAndNewlines)
hhmessages.insert(messagetext as AnyObject, at: hhmessages.endIndex)
let indexPath = IndexPath(row: hhmessages.count - 1, section: 0)
tableView.beginUpdates()
tableView.insertRows(at: [indexPath], with: .automatic)
tableView.endUpdates()
tableView.transform = CGAffineTransform(rotationAngle: -(CGFloat)(Double.pi));
tableView.scrollToRow(at: indexPath, at: .bottom, animated: true)
replyTxt.text = ""
textViewDidChange(replyTxt)
let recipient = messages["username"] as! String
let rid = String(describing: messages["recipient_id"]!)
let uuid = messages["uuid"] as! String
puuid = UUID().uuidString
// prepare request
let url = URL(string: "http://localhost/messagepost.php")!
let body = "sender_id=\(user_id)&sender=\(username)&text=\(messagetext)&recipient_id=\(rid)&recipient=\(recipient)&uuid=\(uuid)&puuid=\(puuid)"
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.httpBody = body.data(using: .utf8)
// send request
URLSession.shared.dataTask(with: request) { (data, response, error) in
DispatchQueue.main.async {
// error happened
if error != nil {
Helper().showAlert(title: "Server Error", message: error!.localizedDescription, in: self)
return
}
do {
// converting received data from the server into json format
let json = try JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? NSDictionary
// safe mode of casting json
guard let parsedJSON = json else {
return
}
// if the status of JSON is 200 - success
if parsedJSON["status"] as! String == "200" {
} else {
Helper().showAlert(title: "400", message: parsedJSON["status"] as! String, in: self)
return
}
// json error
} catch {
Helper().showAlert(title: "JSON Error", message: error.localizedDescription, in: self)
return
}
}
}.resume()
}
// exec-d whenever delegated textView has been changed by chars
func textViewDidChange(_ textView: UITextView) {
// declaring new size of the textView. we increase the height
let new_size = textView.sizeThatFits(CGSize.init(width: textView.frame.width, height: CGFloat(MAXFLOAT)))
// assign new size to the textView
textView.frame.size = CGSize.init(width: CGFloat(fmaxf(Float(new_size.width), Float(textView.frame.width))), height: new_size.height)
//UIView.animate(withDuration: 0.2) {
self.view.layoutIfNeeded()
//}
}
@IBAction func picSelect_clicked(_ sender: AnyObject) {
// calling picker for selecting iamge
showActionSheet()
}
// this function launches Action Sheet for the photos
func showActionSheet() {
// declaring action sheet
let sheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
// declaring camera button
let camera = UIAlertAction(title: "Camera", style: .default) { (action) in
// if camera available on device, than show
if UIImagePickerController.isSourceTypeAvailable(.camera) {
self.showPicker(with: .camera)
}
}
// declaring library button
let library = UIAlertAction(title: "Photo Library", style: .default) { (action) in
// checking availability of photo library
if UIImagePickerController.isSourceTypeAvailable(.photoLibrary) {
self.showPicker(with: .photoLibrary)
}
}
// declaring cancel button
let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
// adding buttons to the sheet
sheet.addAction(camera)
sheet.addAction(library)
sheet.addAction(cancel)
// present action sheet to the user finally
self.present(sheet, animated: true, completion: nil)
}
// takes us to the PickerController (Controller that allows us to select picture)
func showPicker(with source: UIImagePickerControllerSourceType) {
let picker = UIImagePickerController()
picker.delegate = self
picker.allowsEditing = true
picker.sourceType = source
present(picker, animated: true, completion: nil)
}
// executed whenever the image has been picked via pickerController
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
// accessing selected image
let image = info[UIImagePickerControllerEditedImage] as? UIImage
// assigning selected image to pictureImageView
pictureImg.image = image
// cast boolean as TRUE -> Picture Is Selected
isPictureSelected = true
// remove pickerController
pictureImg.image = info[UIImagePickerControllerEditedImage] as? UIImage
self.dismiss(animated: true, completion: nil)
// cast as a true to save image file in server
if pictureImg.image == info[UIImagePickerControllerEditedImage] as? UIImage {
imageSelected = true
}
dismiss(animated: true, completion: nil)
}
// exec when pictureImageView has been tapped
@IBAction func pictureImageView_tapped(_ sender: Any) {
// declaring action sheet
let sheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
// declaring delete button
let delete = UIAlertAction(title: "Delete", style: .destructive) { (action) in
self.pictureImg.image = UIImage()
}
// declaring cancel button
let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
// adding buttons to the sheet
sheet.addAction(delete)
sheet.addAction(cancel)
// present action sheet to the user finally
self.present(sheet, animated: true, completion: nil)
}
// custom body of HTTP request to upload image file
func createBodyWithParams(_ parameters: [String: String]?, filePathKey: String?, imageDataKey: Data, boundary: String) -> Data {
let body = NSMutableData();
if parameters != nil {
for (key, value) in parameters! {
body.appendString("--\(boundary)\r\n")
body.appendString("Content-Disposition: form-data; name=\"\(key)\"\r\n\r\n")
body.appendString("\(value)\r\n")
}
}
// if file is not selected, it will not upload a file to server, because we did not declare a name file
var filename = ""
if imageSelected == true {
filename = "notes-\(puuid).jpg"
}
let mimetype = "image/jpg"
body.appendString("--\(boundary)\r\n")
body.appendString("Content-Disposition: form-data; name=\"\(filePathKey!)\"; filename=\"\(filename)\"\r\n")
body.appendString("Content-Type: \(mimetype)\r\n\r\n")
body.append(imageDataKey)
body.appendString("\r\n")
body.appendString("--\(boundary)--\r\n")
return body as Data
}
@IBAction func replyBtn_clicked(_ sender: Any) {
if replyTxt.text.isEmpty == false && replyTxt.text.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty == false {
uploadPost()
//tableView.reloadData()
}
}
@objc func keyboardWillChange(notification: NSNotification) {
let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
let deltaY = targetFrame.origin.y - curFrame.origin.y
//print("deltaY",deltaY)
UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
self.replyTxt.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
self.tableView.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
self.replyBtn.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
self.picSelect.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
},completion: nil)
}
func textFieldShouldReturn(_ replyTxt: UITextField) -> Bool {
replyTxt.resignFirstResponder()
return true
}
}
解决方案
问题是你在插入新文本
let indexPath = IndexPath(row: hhmessages.count - 1, section: 0)
这是数组的最后一个字段。但在你的 cellForRow: 你有
let text = hhmessages.reversed()[indexPath.row]["messagetext"] as! String
它在 tableView 的最后一个单元格中显示了数组的第一个字段。
我认为那是你的问题。
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