How to make optional images in a UITableViewCell? - swift

Hi I'm making an app with UIkit and I'm having a problem trying to achieve the layout of a cell.
What I want is to make a cell that has an image header, a stack of user images, and a label. I place this cell in a UITableView. The problem I'm having is that the image header is optional so if it's not there I need it to display like the cell shown below in the attached image.
Can someone who has more knowledge in UIkit help me please?

let suppose you have struct that use to populate tableview
struct User {
let name:String
let headerImage:UIImage? // an optional image
}
your controller
class ViewController:UIViewController {
var users = [User]()
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return users.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if let image = users[indexPath.row].image {
let cell = tableView.dequeueReusableCell(withIdentifier: "UserHeaderCell", for: indexPath) as! UserHeaderCell
return cell
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "UserSimpleCell", for: indexPath) as! UserSimpleCell
return cell
}
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
if let image = users[indexPath.row].image {
return 100 // with image
}
return 50 // without image
}
}
make two cell one for header image and one for simple
class UserHeaderCell:UITableViewCell {
}
class UserSimpleCell:UITableViewCell {
}

Related

My function tableView.didSelectRow is not working

I have a tableView with custom cells and my goal is to be able to click on one and print the number of the current row.
Right now when I click on a cell not happens and I can't understand why.
This is the code:
//MARK: - UITableDataSource
extension ChannelViewController: UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return groupResult.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let group = groupResult[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: K.cellContactNibName, for: indexPath) as! ContactCell
cell.usernameLabel.text = group.name
cell.messageLabel.text = group.recentMessage
let storage = Storage.storage()
let storageRef = storage.reference()
// Reference to an image file in Firebase Storage
let reference = storageRef.child("imagesFolder/\(group.image)")
// UIImageView in your ViewController
let imageView: UIImageView = cell.uImage
// Placeholder image
let placeholderImage = UIImage(named: "MeAvatar")
// Load the image using SDWebImage
imageView.sd_setImage(with: reference, placeholderImage: placeholderImage)
cell.uImage.image = imageView.image
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print("You selected cell #\(indexPath.row)!")
}
}
and as you can see in the screen the single selection is enabled:
change to
extension ChannelViewController: UITableViewDataSource, UITableViewDelegate
or move the method into another extension conformed to UITableViewDelegate
also, remember to set the tableView's delegate to the ChannelViewController

How to maintain highlighted multiple UITableView rows after reloading UITableView?

I have a UITableView.
I can select multiple cells make them highlighted.
But, whenever I reload App, the selected and highlighted state disappears.
I think I need to put some codes in 'viewDidAppear' and 'didSelectRowAt'. But I don't have any idea of specific codes.
What do I have to put in this syntax?
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
tableView.reloadData()
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
}
I recommend u add to dataSource item field selected, and in method cellForRowAtindexPath configure by your dataSource items.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cellClass = (self.cellClass(for: indexPath) ?? self.cellClasses.first) else { return UITableViewCell() }
let cell = tableView.dequeueReusableCell(withIdentifier: cellClass.identifier, for: indexPath)
if let configurable = cell as? ConfigurableComponent, let object = self.object(at: indexPath) {
let item = self.dataSource[indexPath.row]
configurable.selected = item.selected
}
return cell
}
When call didSelectRowAt, just take item and change selected field, sample:
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let item = self.dataSource[indexPath.row]
item.selected = !item.selected
tableView.reloadData()
}

Why is the width of cell in UItableview not same as width of screen in simulator?

The table cell is running shorter than it is supposed to be. (I use different background colour which shows difference width) The setting of cell is custom (only row height is change to 140). The playerCell class has nothing but some IBoutlets. Thanks.
(image: storyboard
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
var count: Int
if playerBank.count == 0
{
count = 1
}
else{
count = playerBank.count
}
return count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! playerCell
if playerBank.isEmpty{
let p = Player()
playerBank = setInvalidPlayer(pBank: p, userInput: userInputPlayerName)
}
let playerInBank: Player = playerBank[indexPath.row]
passImageUrl = cell.setPlayerCell(p: playerInBank)
urlBank.append(passImageUrl)
let bgColorView = UIView()
bgColorView.backgroundColor = UIColor.red
cell.selectedBackgroundView = bgColorView
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
myIndex = indexPath.row
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ShowPlayerInfo", sender: self)
}
}
My first guess is that, while you have a custom cell with custom outlets, that there are no layout constraints in place. So the items that you put into the storyboard are retaining their intrinsic values and not adapting to the device screen size.
If you add constraints to those outlets, especially enough to where the width of the cell can be determined based on the rest of the elements, then your cell should display full width.

didSelectRowAt from custom cell do nothing

below code supposed to call usernames from an array and user able to tap on the desired username. call to that array is a success and I can see the usernames but won't able to tap into it. and it don't even print "didSelectRowAt". appreciate your help. thanks.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let cell = tableView.dequeueReusableCell(withIdentifier: "cellIdentifier", for: indexPath) as! MentionUserCell
cell.username!.text = autoComplete[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return autoComplete.count
}
func numberOfSections(in tableView: UITableView) -> Int
{
return 1
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath)
{
let selectedCell: MentionUserCell = tableView.cellForRow(at: indexPath)! as! MentionUserCell
let selectedWord: String = selectedCell.username!.text! + " "
print("didSelectRowAt")
var string: NSString = NSString(string: self.commentTextView.text!)
string = string.replacingCharacters(in: otoCadang.sharedInstance.foundRange, with: selectedWord) as NSString
// change text field value
commentTextView.text = string as? String
// change cursor position
let positionOriginal = commentTextView.beginningOfDocument
if let cursorLocation: UITextPosition = self.commentTextView.position(from: positionOriginal, offset: otoCadang.sharedInstance.foundRange.location + selectedWord.characters.count)
{
self.commentTextView.selectedTextRange = self.commentTextView.textRange(from: cursorLocation, to: cursorLocation)
}
// remove suggestion
self.autoComplete.removeAll()
self.tableView.reloadData()
tableView.isHidden = true
}
Check List
tableview delegate is set properly
tableview selection mode == No Selection, then change to single selection
function name is correct func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
are you using any tap gesture on this view? remove it.
If you are editing UITextView will can't call to `didselectRowAt. Try to get the Your MentionUserCell, IndexPath in UITextView's methods and handle there. Example:
func textViewDidChange(_ textView: UITextView) {
var parentView = textView as UIView
while !(parentView is UITableViewCell) {
parentView = parentView.superview!
}
if let cell: MentionUserCell = parentView as? MentionUserCell {
if let indexPath = self.tableView.indexPath(for: cell) {
let yourIndexPath = indexPath
}
}
//your code
}
Hope it will help you.
When are using two or more cells the didSelectRow method is not working Well. You can use a button in cell.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellIdentifierName", for: indexPath) as! MentionUserCell
cell.username!.text = autoComplete[indexPath.row]
let button = cell.viewWithTag(101) as! UIButton
button.cellclick.addTarget(self, action: #selector(functionName(sender:)), for: .touchDown)
return cell
}
Now you get the indexPath:-
func functionName(sender:UIButton) {
let buttonPosition:CGPoint = sender.convert(CGPoint.zero, to:self.tableview)
let indexPath = self.tableview.indexPathForRow(at: buttonPosition)
print(indexPath.row)
}

tableview persisting cell image after reloading

I have a tableview with cells that when selected displays an image within the selected cell, this image then disappears when the cell is selected again, and so on. When i press a submit button the selected cells are remembered and the tableview reloads with new data. But when doing this all the new data loads but the selected cell image persists. I have tried calling tableView.reloadData() on the main queue but it still persists. The image also persists when i press the submit button several times.
Heres my code:
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return currentQuestion.answers.count
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return tableView.frame.height/CGFloat(currentQuestion.answers.count)
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
setSelectedArray()
let cell: AnswersTableViewCell = tableView.dequeueReusableCell(withIdentifier: "answersTableViewCell") as! AnswersTableViewCell
let text = currentQuestion.answers[indexPath.row]
let isAnAnswer = currentQuestion.answerKeys[indexPath.row]
cell.answerTextLabel.text = text
cell.answerView.backgroundColor = UIColor.white.withAlphaComponent(0.5)
cell.contentView.sendSubview(toBack: cell.answerView)
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
if let cell: AnswersTableViewCell = tableView.cellForRow(at: indexPath) as? AnswersTableViewCell {
if cell.answerImageView.image == nil {
cell.answerImageView.image = UIImage(named: "paw.png")
selected[indexPath.row] = true
} else {
cell.answerImageView.image = nil
selected[indexPath.row] = false
}
}
}
#IBAction func submitButtonWasPressed() {
if questionNumber < questions.count - 1 {
questionNumber += 1
setCurrentQuestion()
self.answersTableView.reloadData()
self.view.setNeedsDisplay()
}
}
Any help would be great. Thanks
You need to set the image back to its correct value in cellForRow. Cells in your table are reused between calls to reloadData, and since you're not touching the imageView, it's keeping its previous value. Looks to me like you want:
cell.answerImageView.image = selected[indexPath.row] ? UIImage(named: "paw.png") : nil
inside of tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath).