My Data Changes in Uitableviewcell When I Scroll Down and Get Back

My data changes in UITableViewCell when I scroll down and get back

it is because your cells are being reused :

// this line initialize a cell of type shopsTableViewCell 
//if no cell can be reused, get an already used cell else
let cell : shopsTableViewCell 
                 = tableView.dequeueReusableCellWithIdentifier("shopCell",
                                  forIndexPath: indexPath) as! shopsTableViewCell

so image and other data should be the last image and data of the dequeued cell.

To avoid this, you shall implement prepareForReuse in the cell class file to reset data and image. docs of apple about prepareForReuse func

From Apple docs :

If a UITableViewCell object is reusable—that is, it has a reuse identifier—this method is invoked just before the object is returned from the UITableView method dequeueReusableCellWithIdentifier:. For performance reasons, you should only reset attributes of the cell that are not related to content, for example, alpha, editing, and selection state. The table view's delegate in tableView:cellForRowAtIndexPath: should always reset all content when reusing a cell. If the cell object does not have an associated reuse identifier, this method is not called. If you override this method, you must be sure to invoke the superclass implementation.

 //Example :
 override func prepareForReuse() {
    super.prepareForReuse()
    //Do reset here
    this.shopImg?.image = nil
    this.shopName?.text = ""
    this.shopDescription?.text = ""

}

UITableViewCell Data changes after scrolling

Create UITableViewCell subclass and override prepeareForReuse function - to turn cell to default mode.

Swift:

override func prepareForReuse() {
    super.prepareForReuse()

    //set cell to initial state here, reset or set values, etc.
}

As per your comment - of how to subclass UITableViewCell:

import UIKit

class MyCustomCell: UITableViewCell {
     // things that you can do here:
     // initialise your properties here. (label, textfield. etc)
     // layout subviews.
     // override superclass APIs.
}

Selection of UITableViewCell Changes when Scroll down in Swift

cellForRowAt will be called every time that cell is displayed.
you need selected list to save selected index.

var listSelected: [Int] = []

and

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    
    let cell = tableView.dequeueReusableCell(withIdentifier: "TasksTableViewCell") as! TasksTableViewCell
    
    cell.backView.backgroundColor = listSelected.contains(indexPath.row) ? UIColor(named: "primaryViewColor") : .white
    
    return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    if listSelected.contains(indexPath.row) {
        listSelected = listSelected.filter{$0 != indexPath.row}
    } else {
        listSelected.append(indexPath.row)
    }
    
    tableView.reloadRows(at: [indexPath], with: .automatic)
    
}

Swift UITableView Cell changes image when scrolled

You need to save the change of state in your data model somewhere, and then edit your data source methods (specifically cellForRowAtindexPath) to show the cell in its new selected state.

This is true of any change you make to a cell. If the cell scrolls off-screen, it gets recycled and any customizations you've made to it's views will not longer be associated with that indexPath any more. So when the user takes action on a cell, you always need to record the information in your data model.

Value changes on scroll UITableView

In your UITableViewCell PostCellImage subclass you should override prepeareForReuse function - to turn cell to default mode.

Swift:

override func prepareForReuse() {
    super.prepareForReuse()

    //set cell to initial state here 
    //set like button to initial state - title, font, color, etc.
}

Tableview cell setting keep changed when I scroll down and get back swift

The reason for this is cell reuse.

It means cells that have already been styled in a certain way can be reused to display different data. You have to make sure that you setup every aspect of the styling each time a cell is reused to avoid cross over.

It might be easier to keep track of the styling if you make a configureCell method to handle it, this way you can't forget to set one value and you could even set some default values.

func configureCell(cell:RosterCell,
               textColour:UIColor,
               seperatorColour:UIColor,
               buttonEnabled:Bool,
               buttonAlpha:CGFloat,
               interactionEnabled:Bool = false) {

        cell.separator.backgroundColor = seperatorColour
        cell.jobDetail.textColor = textColour
        cell.button.isEnabled = buttonEnabled
        cell.button.alpha = buttonAlpha
        cell.isUserInteractionEnabled = interactionEnabled

}

Then your cellForRowAt method would look like this

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "rosterId", for: indexPath) as! RosterCell
    ...
    if jobCancel[indexPath.section] == 0{
        configureCell(cell: cell,
                  textColour: UIColor.gray,
                  seperatorColour: UIColor.darkGray,
                  buttonEnabled: false,
                  buttonAlpha: 0.3,
                  interactionEnabled: true)
    }
    if cell.jobDetail.text == "Cancelled Schedule"{
        configureCell(cell: cell,
                  textColour: UIColor.gray,
                  seperatorColour: UIColor.red,
                  buttonEnabled: false,
                  buttonAlpha: 0.3)
    }
    if cell.jobDetail.text == "Off Day"{
        configureCell(cell: cell,
                  textColour: UIColor.gray,
                  seperatorColour: UIColor.darkGray,
                  buttonEnabled: false,
                  buttonAlpha: 0.3)
    }

}

As you can see I have set the interactionEnabled parameter to default to false so I did not need to set it for the last two if statements.

Images in UITableViewCell change after scrolling down and back up

In your table view cell PostTableViewCell you need to implement the method

 override func prepareForReuse() {
    super.prepareForReuse()
    self.postImageView.image = nil
    // Set cell to initial state here, reset or set values
}

The cells are holding on to their old content

Swift UITableViewCell - Cell Image changes if I scroll down too fast, but only on the first attempt

This occurs because of

1- cell dequeueing : cells are re-used inside the tableView

2- when you scroll before a request happens it may cause a new 1 with same url

Best option is using SDWebImage

When I scroll down in my TableView, the cell data changes - Swift 4

You update number every time the table view asks for a cell. That has no direct relation to the row being displayed.

It's unclear why you even have the number property.

If you just want to show the corresponding row number in each cell, get rid of the number property and update:

cell.textLabel?.text = "\(number)"

with:

cell.textLabel?.text = "\(indexPath.row)"

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