update
now images displays as they are loaded, but there still a problem I can't solve.
The images overlaps the content of the cell even the three views are in a vertical stack (first is the image, the next two are label views).
I wonder how can a view overlap other views in a stackview
now my talbe view delegate method looks like this:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
var cell: BaseTableViewCell!
if let contents = contents {
let content = contents[indexPath.row]
if let imageUrl = content.imageUrl, let url = URL(string: imageUrl) {
cell = tableView.dequeueReusableCell(withIdentifier: "ImageContentRow", for: indexPath) as! ContentWithImageTableViewCell
Alamofire.request(url).responseImage(completionHandler: { (response) in
if let image = response.result.value {
cell.imageView?.image = image
cell.setNeedsLayout()
}
})
}else{
cell = tableView.dequeueReusableCell(withIdentifier: "ContentRow", for: indexPath) as! ContentTableViewCell
}
cell.contentTitleVeiw.text = content.title
cell.contentLeadView.text = content.lead
}
return cell!
}
I'm very new to iOS. I've already tutorials and watched video courses and now I would like to implement my very first app.
I try to read a feed and display the content's title, lead and image (if it has any).
I defined a cell, with an UIMageVeiw, and two UILables, at last I embedded them into a vertical StackView (I set distribution to Fill).
Everything works well, but images don't display automatically, just if I click on the cell, or sroll the TableVeiw.
And even if I set the image view to Aspect Fit (and embedded it into the top tof the vertical stack view), when the image displays it keeps it's original size and overlaps the cell content.
I've trying to find out what I do wrong for two days, but I can't solve it.
I try display data like this:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
var cell: BaseTableViewCell!
if let contents = contents {
let content = contents[indexPath.row]
if let imageUrl = content.imageUrl, let url = URL(string: imageUrl) {
cell = tableView.dequeueReusableCell(withIdentifier: "ImageContentRow", for: indexPath) as! ContentWithImageTableViewCell
cell.imageView?.af_setImage(withURL: url)
}else{
cell = tableView.dequeueReusableCell(withIdentifier: "ContentRow", for: indexPath) as! ContentTableViewCell
}
cell.contentTitleVeiw.text = content.title
cell.contentLeadView.text = content.lead
}
return cell!
}
The image view cell's view hierarchy looks like this:
My list looks like this after I start my app and data displayed:
After I click on a cell that should display an image or scroll it out and back the result is this:
At least this is my list view controller with the two prototype cells
(one for contents with image, one for without image)
You need to notify the tableView that the image was loaded and that it has to redraw the cell.
Try changing
cell.imageView?.af_setImage(withURL: url)
to
cell.imageView?.af_setImage(withURL: url, completion: { (_) in
self.tableView.beginUpdates()
self.tableView.setNeedsDisplay()
self.tableView.endUpdates()
})
Take a look at my answer here - in the end you might need to explicitly set height on the imageView.
Related
The problem is that I don't know how to refresh images loaded asynchronously from url with SDWebImage.
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
let item = items[indexPath.row]
if let url = URL(string: item.stringUrl) {
let placeholderImage = UIImage(named: "noPhoto.png")
itemImage.sd_setImage(with: url, placeholderImage: placeholderImage)
}
cell.imageView?.image = itemImage.image
cell.textLabel?.text = item.title
cell.detailTextLabel?.text = "item id: \(item.id)"
return cell
}
The images will only refresh after scrolling through the table. Until then the table only shows placeHolder image which is expected as it only reloads images when cells are reused. I tried to use the completion handler to refresh images when loaded using tableview.reload() as shown below:
itemImage.sd_setImage(with: url, placeholderImage: placeholderImage, completed: {image,error,cache,url in
if image != nil {
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
})
This solution results in tableView loading all the images in a second which is what I want but it reloads the whole table basically every time I try to scroll through it so it "pushes" the whole table to the top position instantly.
The last solution I tries is this:
itemImage.sd_setImage(with: url, placeholderImage: placeholderImage, completed: {image,error,cache,url in
if image != nil {
DispatchQueue.main.async {
self.tableView.reloadRows(at: [indexPath], with: .none)
}
}
})
This also doesn't and makes tableview randomly showing and hiding images.
I suppose the problem is that I try to reload images in a function that creates cells but I can't find a solution to how resolve this issue. I will be very grateful for any help.
I am trying to achieve a layout like this
My tableview has 3 cells (SubItemsCell (main cell), SubItemsListCell(n number of products inside main cell) and noSubstituteCell (fixed cell after the second cell count 1))
SubItemsCell has a "SELECT" Button that will expand and show SubItemsListCell, this cell will load as (dynamic) any count of products under the main SubItems Cell.
NoSubstitute Cell comes after the n number of products loads.
What my expected result is first load main cell that is self.archivedProducts and when u click each archived product's select button it expand and load self.newproducts and nosubstitute static cell. So main cell paired up with those 2 cells and show at once when we expand only.
So far I just loaded Main Cell only. I have no idea what should I do next, please give me an idea with a code or very similar example.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cell = tableView.dequeueReusableCell(withIdentifier: "SubItemsCell", for: indexPath) as? SubItemsCell else {
fatalError ("SubstituteItems Cell not found!")
}
let product = self.archivedProducts[indexPath.row]
cell.titleLabel.text = product.title ?? ""
cell.priceLabel.text = "AED \(String(format: "%.2f", product.price ?? 0.00))"
cell.scaleLabel.text = product.uom ?? ""
cell.unavailableLabel.isHidden = false
cell.selectBtn.isHidden = false
let imageUrl = product.image?.url
let escapedUrl = imageUrl?.replacingOccurrences(of: "\\", with: "")
let replacedUrl = "\(escapedUrl ?? "")"
let url = URL(string: replacedUrl)
let plImage = UIImage(named: "whiteBg")
DispatchQueue.main.async {
cell.thumbImage.kf.setImage(with: url, placeholder: plImage, options: [.transition(.fade(0.2))])
}
}
I don't think you need a nested tableview. You can achieve the above with other elements. In order to achieve the layout above, my suggestion is the following:
Subclass your UITableViewCell into at least 2 different formats. There's a lot of ways to do this, my suggestion is to use a CocoaTouch Class w/ XIB (tutorial here) so you can be meticulous with the layout and constraints:
a. CellWDropdown (Cell #1 shown): You have a cell prototype that will include the image, the 3 labels in question and a button which act as the dropdown and will invoke a UIPickerView.
b. CellWStepper (Cells #2 and #3) : You'll have your image and 2 labels and what's called UIStepper for the +/- buttons
c. LastCell (Cell #4 if that's a cell? It could also be a view): likewise create the needed UI elements and constrain them appropriately.
Register the nib file you created:
tableView.register(UINib(nibName: "CellWDropDown", bundle: nil), forCellReuseIdentifier: "cellWDropdownIdentifier")
In cellForRowAt method, you invoke the XIBs created above to make the cell views based on the index OR desired cell type for example:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if indexPath.row == 0 {
let cell = tableView.dequeueReusableCell(withIdentifier: cellWDropdownIdentifier, for: indexPath) as! CellWDropdown
}
else if(indexPath.row == 1 || indexPath.row == 2){
let cell = tableView.dequeueReusableCell(withIdentifier: cellWStepperIdentifier, for: indexPath) as! CellWStepper
}
//do other actions/styling
}
Hook up delegate relationships/methods between the nibs you created and the UITableViewController. This is going to application specific.
There's a lot of detail that will have to fill in the gaps but this should put a major dent in getting started
I have a tableView that contains a UIImageView and if the Image has a URL then the image displays and if not then no Image is displayed. The issue I have is that if there is no Image then a big blank spot occurs in the TableView as if there was an image. Is there a way to reduce the blank spot or hide it (Images below) ? The image is the big UIImageView in the center . This is my code when it comes to the Images
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "MyFeed", for: indexPath) as! MyFeed
if stream_image_string[indexPath.row].characters.count > 2 {
let strCellImageURL = self.stream_image_string[indexPath.row]
let imgURL: NSURL = NSURL(string: strCellImageURL)!
let request:NSURLRequest = NSURLRequest(url: imgURL as URL)
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let task = session.dataTask(with: request as URLRequest, completionHandler: {(data, response, error) in
DispatchQueue.main.async(execute: { () -> Void in
cell.post_image.image = UIImage(data: data!)
})
});
task.resume()
} else {
cell.post_image!.isHidden = true
cell.post_image!.image = nil
}
return cell
}
Essentially if the String coming back has 2 or more characters then it's a valid URL and the image is downloaded; the part that I am focused on is the else statement and this code
else {
cell.post_image!.isHidden = true
cell.post_image!.image = nil
}
So obviously if it goes in the else statement then there is no image and I set the Image to null or nil then I try to hide the extra white space by setting the Image to hidden however that does not work . Any idea on how I can hide the white space ? I have also been reading this question but it does not work iOS swift imageView cannot be hidden in TableViewCell
Give outlet of image's width and if there is no image then set constant of that outlet to "0".
e.g.
if(!image)
{
widthOfImage.constant = 0
}
I experienced the same problem myself. You need to create 2 cells for this. Like this:
override func tableView (_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if (stream_image_string[indexPath.row] == "")
{
let cell = tableView.dequeueReusableCell (withIdentifier: "noImageMyFeed", for: indexPath) as! noImageMyFeed
return cell
}
else
{
let cell = tableView.dequeueReusableCell (withIdentifier: "MyFeed", for: indexPath) as! MyFeed
return cell
}
}
this video will help you in detail : https://www.youtube.com/watch?v=FAxtWtqeMIM
adapt the video to its own content, create a cell from scratch by simply deleting the image part
I'm going through Stanford's cs193p. Assignment 4 has us create a custom UITableVIewCell and load a picture from the web into a UIImageView inside the cell.
My UIImageView and my Cell have their content mode set to Aspect Fit on the story board.And the ImageView is set on autolayout to be hugging the cell.
And yet when the picture first loads, it will bleed out of the UIImageView. When I click on it, it will correctly aspect fit.
I tried setting the content mode in code just before assigning the image, but that also didn't work. I also tried calling layoutSubviews() and setNeedsLayout right after assigning the image, and while that helps by actually showing the image (as opposed to showing nothing until the user clicks the cell), it still shows in the wrong size until the user clicks it.
This is the code for the cell:
import UIKit
class ImageTableViewCell: UITableViewCell {
#IBOutlet weak var pictureView: UIImageView!
var pictureURL: URL? {
didSet {
fetchImage()
}
}
fileprivate func fetchImage() {
if let url = pictureURL {
pictureView.image = nil
let queue = DispatchQueue(label: "image fetcher", qos: .userInitiated)
queue.async { [weak weakSelf = self] in
do {
let contentsOfURL = try Data(contentsOf: url)
DispatchQueue.main.async {
if url == self.pictureURL {
weakSelf?.pictureView?.image = UIImage(data: contentsOfURL)
weakSelf?.layoutSubviews()
print("loaded")
}
}
} catch let exception {
print(exception.localizedDescription)
}
}
}
}
}
This is the code that loads the cell on its TableViewController:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
var cell = UITableViewCell()
switch indexPath.section {
case 0:
cell = tableView.dequeueReusableCell(withIdentifier: "imageCell", for: indexPath)
if let imageCell = cell as? ImageTableViewCell {
imageCell.pictureURL = tweet?.media[indexPath.row].url
// other stuff not programmed yet
}
return cell
The code that gives me the cell's height:
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
if indexPath.row == 0 && tweet != nil {
let media = tweet?.media[indexPath.row]
return tableView.frame.width / CGFloat(media!.aspectRatio)
}
return UITableViewAutomaticDimension
}
I'm sorry for pasting all this code, but I have no idea where the problem is so I'm putting everything I can this might be related.
You should set content mode first and then you should set the frame of your imageview, so once you should try to set content mode in awakeFromNib of tableview subclass or from cellforrowatindexpath before setting image to it!
Or you can set your content mode from interface builder (from storyboard!) - > select your imageview - > fro attribute inspector - > select mode(under view) to Aspect fit
Well, following an answer on reddit, I deleted the table view controller and remade it, setting all the outlets again. It worked, I guess it was a problem in Xcode?
So if you're having a problem like this, try remaking your storyboard.
I am using SDWebImage library to download image and load into image view inside a table cell.
I want to resize the table cell after the image is downloaded. Please advice. Many thanks.
Cell is not resize correctly after image set into image view
Cell resize correctly after dequeue and load again
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier(GagListTableViewCell.cellId, forIndexPath: indexPath) as! GagListTableViewCell
cell.layoutMargins = UIEdgeInsetsZero
let gagDataCommand = gagDataSource[indexPath.row]
if let caption = gagDataCommand.caption {
cell.captionLabel.text = caption
}
if let imageUrlStr = gagDataCommand.images?.normal {
if let imageUrl = NSURL(string: imageUrlStr) {
cell.gagImage.sd_setImageWithURL(imageUrl, placeholderImage: UIImage(named: AppConstants.imagePlaceHolderName), completed: { (image, error, cacheType, url) in
//guess I need to redraw the layout here
})
} else {
//fail to get image url, set placeholder image to the cell instead
cell.gagImage.image = UIImage(named: AppConstants.imagePlaceHolderName)
}
}
return cell
}
You could use automatic dimension for tableview cell.
tableView.rowHeight = UITableViewAutomaticDimension