My JsonData -
let imagestring : String? = (myData as AnyObject).value(forKey: "Post_mid_image") as? String
if imagestring != nil {
let imageTrueString = "https://www.zdoof.com/" + imagestring!
self.imageStringArray.append(imageTrueString )
}
if let NameString = (myData as AnyObject).value(forKey: "Name") as? String {
self.nameStringArray.append(NameString)
}
When i am trying to set it to the table view cell
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.postLableArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "reUse", for: indexPath)
let myImage = cell.viewWithTag(30) as! UIImageView
myImage.clipsToBounds = true
if indexPath.row < imageStringArray.count {
if let myImageString = imageStringArray[indexPath.row] as? String {
let ImageUrl = URL.init(string: myImageString)
myImage.kf.setImage(with: ImageUrl)
}
}
return cell
}
The image is repeating in every cell . Why it is happening ? Please help
As per the response you have given, you can show the image like below:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let dict = myData as AnyObject
let cell = tableView.dequeueReusableCell(withIdentifier: "reUse", for: indexPath)
let myImage = cell.viewWithTag(30) as! UIImageView
if dict["Post_mid_image"] != nil {
let imageUrl = URL.init(string: strImageUrl)
myImage.kf.setImage(with: imageUrl)
} else {
//Set placeholder image showing no image available
}
return cell
}
Problem is with cell re-usablity of table view here ,you have to handle it , you can have SDWebImage library for loading images in cell or you can have your own image cache which caches images with key/values , key as in image url , so dynamically checking image url for item at indexpath and load cached image with that image url as key.
Hope it helps!!
This is happening because of using tableView.dequeueReusableCell(withIdentifier: "reUse", for: indexPath).
Basically whenever you use dequeueReusableCell(withIdentifier:,For:), it will use the same cell for all of data. It means the total number of cell which are on screen are only going to load, for all other cell, it will use same cell with different value.
now consider a scenario that you are having 500 cells in tableview, but we can manage at most 10-15 cells in display, so for all other cells it will use same cells just modify the value of cell.
so what you can do here is, whenever you use if statement, don't forgot to add else too.
because for one scenario if cell's background is set to red, than we need to add else for another scenario, as cells are just repeated.
Related
I've an avatar image in cells in a table. When I touch a cell (highlight) it shows default avatar image instead of the actual image. I'm not sure what is causing this and how to fix. Any help?
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cell = tableView.dequeueReusableCell(withIdentifier: "TableViewCell", for: indexPath) as? TableViewCell else {
fatalError("Can't find cell")
}
//...
cell.selectionStyle = .default
self.configCell(cell: cell, indexPath: indexPath)
//...
}
func configCell(cell: TableViewCell, indexPath: IndexPath) {
//...
// Avatar
if let url = URL(string: urlString) {
cell.avatarImageView.image = .defaultImage
cell.tag = indexPath.row
let task = URLSession.shared.dataTask(with: url) { data, response, error in
guard let data = data, error == nil else { return }
DispatchQueue.main.async {
if cell.tag == indexPath.row {
cell.avatarImageView.image = UIImage(data: data)
}
}
}
task.resume()
}
//...
}
If you have an issue only with proper image displaying, I'd suggest working with highlightedImage property of UIImageView.
UITableViewCell has .highlighted property (when the cell is pressed down). Thus, if the cell contains UIImageView inside, then when you select/highlight the cell, the UIImageView will use the .highlightedImage instead of just .image.
So just as a backup and fix to the problem, you could additionally provide/tell UIImageView to display an avatar even when it is highlighted.
I have ViewController with button. When I press on button I move to TableViewController with images in cells. I have array with 300 images.
But when I press on button my app paused for 12-14 seconds to load an array of images. After 14 second I move to TableViewController. How to fix it?
class TableViewController: UITableViewController {
var imageArray: [UIImage] =
[UIImage(named: "1.jpg")!,
...
UIImage(named: "300.jpg")!]
var textArray: [String] = ["text1", ... "text300"]
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return textArray
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! TableViewCell
cell.cardImageView.image = imageArray[indexPath.row]
cell.label.text = "\(textArray[indexPath.row])"
}
}
Rather than creating an array of images straight out why don't you try this:
For numberOfRowsInSection set:
return 299
Add this method to your Viewcontroller:
func loadImageAsync(imageName: String, completion: #escaping (UIImage) -> ()) {
DispatchQueue.global(qos: .userInteractive).async {
guard let image = UIImage(named: imageName) else {return}
DispatchQueue.main.async {
completion(image)
}
}
}
in your tableView cellForRowAt all you will have to call is:
loadImageAsync(imageName: "\(indexPath.row + 1).jpg") { (image) in
cell.cardImageView.image = image
}
cell.label.text = "text\\(indexPath.row + 1)"
It means the app will only have to load the images on demand instead of making a huge array of images that it may never use if the user doesn't scroll all the way down. A 300 image array would be very CPU and memory intensive to create.
Don't store the object of UIImage in the array, as your code suggested, your images are locally stored as asset, just load the image names.
instead of this
var imageArray: [UIImage] =
[UIImage(named: "1.jpg")!,
...
UIImage(named: "300.jpg")!]
Do this
var imageNameArray: [String] =
["1.jpg",
...
"300.jpg"]
In the cellForRowAtIndexPath do following
cell.cardImageView.image = UIImage(named: imageArray[indexPath.row])
You could load the image data in background thread, once available then set it. But this approach has several shortcoming. If you do this you have to manually manage the image caching mechanism, because you dont want to load same image twice while shown twice in the cell.
There is a good news for you that, Uiimage(named:) method is thread safe for iOS9+. So if you are targeting iOS9+ you can load the image using UIImage(named:) in background thread. It will automatically manage the caching mechanism
DispatchQueue.global(qos: .background).async {
// load image here
let image = UIImage(named......
DispatchQueue.main.async {
// set image here
cell.card........
}
}
one possible bug may arise in this approach, such that while scrolling fast you may see old images for a while. You could solve it easily by managing the indexpath for which this image was loaded and comparing with current one.
I believe you should perform some kind of lazy initialization here so you get the benefit of cell reusing.
your code must be like this:
var imageTitles: [String] =
"1.jpg",
...
"300.jpg"]
var textArray: [String] = ["text1", ... "text300"]
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return textArray.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! TableViewCell
cell.cardImageView.image = UIImage(named: imageTitles[indexPath.row])
cell.label.text = textArray[indexPath.row]
}
I have a table view that has 100 rows. What I'd like to do is set an image for the row if the index of the row is in my array that I have. What I've found is that it only sets the image for the first number in the array. So, in this example, I have [2,3,4,5] in my array. The result is that it is setting the image for the row where index = 2. Rather than for all the numbers. Any help on this would be greatly appreciated!
var completedWorkoutsArray = [2,3,4,5]
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellReuseIdentifier")! //1.
let text = data[indexPath.row]
cell.textLabel?.text = text
for i in completedWorkoutsArray {
if(indexPath.row == i) {
let image: UIImage = checkmark!
cell.imageView!.image = image
}
else
{
let image: UIImage = redX!
cell.imageView!.image = image
}
}
return cell
}
You want something like this:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellReuseIdentifier")!
let text = data[indexPath.row]
cell.textLabel?.text = text
let image = completedWorkoutsArray.contains(indexPath.row) ? checkmark : redX
cell.imageView.image = image
return cell
}
Your code fails because it loops through all values in the array. It sets the image each and every time. The last image set is the one you see.
I am fetching previously selected categorylist from the server. say for an example.cateogrylist i fetched from the server was in following formate
categoryid : 2,6,12,17
now what i need to do is want to enable checkmark in my tableview based on this categorylist,for that purpose i converted this list into an [Int] array like this :
func get_numbers(stringtext:String) -> [Int] {
let StringRecordedArr = stringtext.components(separatedBy: ",")
return StringRecordedArr.map { Int($0)!}
}
in viewDidLoad() :
selectedCells = self.get_numbers(stringtext: UpdateMedicalReportDetailsViewController.catId)
print(myselection)
while printing it's giving me results like this : [12,17,6,8,10]
i want to enable checkimage based on this array.I tried some code while printing its giving me the right result like whatever the categories i selected at the time of posting ,i am able to fetch it but failed to place back this selection in tableview.Requirement : while i open this page it should show me the selection based on the categorylist i fetched from the server.
var selectedCells : [Int] = []
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let cell1 = table.dequeueReusableCell(withIdentifier: "mycell") as! catcell
cell1.mytext.text = categoriesName[indexPath.row]
if UpdateMedicalReportDetailsViewController.flag == 1
{
selectedCells = self.get_numbers(stringtext: UpdateMedicalReportDetailsViewController.catId)
cell1.checkimage.image = another
print(selectedCells)
}
else
{
selectedCells = []
cell1.checkimage.image = myimage
}
return cell1
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let cell = table.cellForRow(at: indexPath) as! catcell
cell.checkimage.image = myimage
if cell.isSelected == true
{
self.selectedCells.append(indexPath.row)
cell.checkimage.image = another
}
}
func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
let cell = table.cellForRow(at: indexPath) as! catcell
if cell.isSelected == false
{
self.selectedCells.remove(at: self.selectedCells.index(of: indexPath.row)!)
cell.checkimage.image = myimage
}
}
output :
This is a very common use case in most apps. I'm assuming you have an array of all categories, and then an array of selected categories. What you need to do is in cellForRowAtIndexPath, check to see if the current index path row's corresponding category in the "all categories" array is also present in the "selected categories" array. You can do this by comparing id's etc.
If you have a match, then you know that the cell needs to be selected/checked. A clean way to do this is give your cell subclass a custom load method and you can pass a flag for selected/checked.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = table.dequeueReusableCell(withIdentifier: "mycell") as! catcell
let category = self.categories[indexPath.row] // Let's say category is a string "hello"
Bool selected = self.selectedCategories.contains(category)
cell.load(category, selected)
return cell
}
So with the code above, let's say that categories is just an array of category strings like hello, world, and stackoverflow. We check to see if the selectedCategories array contains the current cell/row's category word.
Let's say that the cell we're setting up has a category of hello, and selectedCategories does contain it. That means the selected bool gets set to true.
We then pass the category and selected values into the cell subclass' load method, and inside that load method you can set the cell's title text to the category and you can check if selected is true or false and if it's true you can display the checked box UI.
I need to get the first cell in my tableView to be a different size from the rest. The rest of my cells are all under the class CustomPFTableViewCell, but the first one is a different cell so its under the class FirstPFTableViewCell, both of which extend from the class PFTableViewCell. Right now, I just used an if depending on the indexPath.row for whether or not the cell was the first cell. When its not it will load data for the cell from Parse.
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath, object: PFObject?) -> PFTableViewCell {
if(indexPath.row >= 1){
let cell = tableView.dequeueReusableCellWithIdentifier("Cell") as! CustomPFTableViewCell!
print("Loading Parse Database Files...")
// Extract values from the PFObject to display in the table cell
if let name = object?["Name"] as? String {
cell?.nameTextLabel?.text = name
print("Loading " + name)
}
if let author = object?["authorName"] as? String {
cell?.authorTextLabel?.text = author
}
if let likes = object?["Likes"] as? Int {
let stringVal = String(likes)
cell?.numLikes.text = stringVal
}
if let descrip = object?["Description"] as? String {
cell?.descriptionHolder = descrip
}
let initialThumbnail = UIImage(named: "Unloaded")
cell.customFlag.image = initialThumbnail
if let thumbnail = object?["imageCover"] as? PFFile {
cell.customFlag.file = thumbnail
cell.customFlag.loadInBackground()
}
return cell
}
print("Finished loading!")
let cell = tableView.dequeueReusableCellWithIdentifier("firstCell") as! PFTableViewCell
return cell
}
The end is empty because I'm not sure how to go about changing the one/first cell's size. (In the Interface Builder its set to 60). I guess the most important part in solving this is this:
let cell = tableView.dequeueReusableCellWithIdentifier("firstCell") as! PFTableViewCell
return cell
}
In order to play with the size of the cell you have to implement the UITableViewDelegate function
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
if indexPath.row == 0 {
return firstCellHeight
} else {
return customCellHeight
}