How to Adjust the Uitableviewcell Height to the Content of Uitextview That's Inside

How can I adjust the UITableViewCell height to the content of UITextView that's inside?

The key to getting self-sizing table cells (autolayout-based, which I recommend) is as follows:

Add your subviews to the contentView of the UITableViewCell
Provide constraints between your subviews and the contentView such that your subviews reach all edges of the table cell. In your case, this probably means aligning the leading, trailing, top, and bottom edges of your UITextView to the corresponding edges of the contentView.
Set the row height to UITableViewAutomaticDimension instead of a hardcoded CGFloat.
Somewhere in your controller, provide an estimation of the height with tableView.estimatedRowHeight = x (a hard coded constant is fine, this is for performance).

Adjust height of UITableViewCell to height of UITextView

I think you need to use self-sizing UITableViewCell. Replace your current implementation of heightForRowAt with the following:

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

    return UITableViewAutomaticDimension
}

Now height of cells in your UITableView object will be calculated automatically based on constraints.
Also, add some estimated value for row height:

func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {

    return 100.0 // You can set any other value, it's up to you
}

Now you will see that the UITextView view fills the whole UITableViewCell cell.

Any way to dynamically adjust the height of a UITextView inside a UIStackView inside a UITableViewCell?

Turns out that just writing out that question in detail and then looking at a different question on StackOverflow allowed me to find one of several answers that described the solution to this predicament.

The answer:

func textViewDidChange(_ textView: UITextView) {
    self.listTableView.beginUpdates()
    self.listTableView.endUpdates()
}

Calling .beginUpdates() and .endUpdates() apparently calls the table view's delegate methods without breaking the editing process like .reloadData() does, allowing for truly dynamic table row height changes while editing a text view inside the table row.

Resize UITableViewCell containing UITextView upon typing

Here is a swift solution that is working fine for me. Provided you are using auto layout, you need assign a value to estimatedRowHeight and then return UITableViewAutomaticDimension for the row height. Finally do something similar to below in the text view delegate.

override func viewDidLoad() {
    super.viewDidLoad()
    self.tableView.estimatedRowHeight = 44.0
}

override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
    return UITableViewAutomaticDimension
}

// MARK: UITextViewDelegate
func textViewDidChange(textView: UITextView) {

    // Calculate if the text view will change height, then only force 
    // the table to update if it does.  Also disable animations to
    // prevent "jankiness".

    let startHeight = textView.frame.size.height
    let calcHeight = textView.sizeThatFits(textView.frame.size).height  //iOS 8+ only

    if startHeight != calcHeight {

        UIView.setAnimationsEnabled(false) // Disable animations
        self.tableView.beginUpdates()
        self.tableView.endUpdates()

        // Might need to insert additional stuff here if scrolls
        // table in an unexpected way.  This scrolls to the bottom
        // of the table. (Though you might need something more
        // complicated if editing in the middle.)

        let scrollTo = self.tableView.contentSize.height - self.tableView.frame.size.height
        self.tableView.setContentOffset(CGPoint(x: 0, y: scrollTo), animated: false)

        UIView.setAnimationsEnabled(true)  // Re-enable animations.
}

How to set UITextView's height dynamically in UITableViewCell based on string size?

When using Auto-Layout for dynamically sizing cells, you don't really need to implement sizeThatFits(...). If the constraints are setup correctly, then you only need to disable the scrolling of the UITextView.

From code:

yourTextView.scrollEnabled = false

From IB:

Select your Text View and open Attributes inspector, then

Sample Image

UITextView inside tableview not resizing according to content

I have tried with UITextView inside UITableViewCell.

Constraints

UITextView, top, bottom and right as 2, 2 and 5, Width as 50. Font Size as 13, Alignment as Center. Give Outlet connection for Width constraints as txtVwWidthConst

UIViewController

@IBOutlet weak var tblView: UITableView!
var textWidthHeightDict = [Int : CGSize]()

override func viewDidAppear(_ animated: Bool) {

    stringValue = [0 : "qwer\nasdasfasdf", 1 : "qwe", 2 : "123123\nasdas\nwqe", 3 : "q\n3\n4", 4 : "klsdfjlsdhfjkhdjkshfjadhskfjhdjksfhkdjsahfjksdhfkhsdfhjksdfjkasklsdfjlsdhfjkhdjkshfjadhskfjhdjksfhkdjsahfjksdhfkhsdfhjksdfjkasklsdfjlsdhfjkhdjkshfjadhskfjhdjksfhkdjsahfjksdhfkhsdfhjksdfjkas"]

    for i in 0..<stringValue.count
    {
        GettingTextViewSize(getStr: stringValue[i]!, fontSize: 14, loopValue: i)
    }
    tblView.reloadData()
}

func GettingTextViewSize(getStr : String, fontSize: CGFloat, loopValue : Int)
{
    var textSize = (getStr as! NSString).size(withAttributes: [NSAttributedStringKey.font : UIFont.systemFont(ofSize: fontSize)])
    if textSize.width > self.tblView.frame.width
    {
        // IF STRING WIDTH GREATER THAN TABLEVIEW WIDTH
        let multipleValue = textSize.width / self.tblView.frame.width
        textSize.height = (textSize.height * (multipleValue + 1.0))
        textSize.width = self.tblView.frame.width

        textWidthHeightDict[loopValue] = textSize
    }
    else
    {
        textSize.height = textSize.height + 10 //ADDING EXTRA SPACE
        textSize.width = textSize.width + 10 //ADDING EXTRA SPACE

        textWidthHeightDict[loopValue] = textSize
    }
}

func numberOfSections(in tableView: UITableView) -> Int {
    return 1
}

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

    return stringValue.count
}

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCell(withIdentifier: "table", for: indexPath) as! TblTableViewCell

    cell.backgroundColor = cellBGColr[indexPath.row]

    cell.txtVw.inputAccessoryView = toolBar
    cell.txtVw.text = stringValue[indexPath.row]
    cell.txtVw.tag = indexPath.row
    cell.txtVwWidthConst.constant = (textWidthHeightDict[indexPath.row]?.width)!
    cell.selectionStyle = .none
    return cell
}

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    var heightVal = (textWidthHeightDict[indexPath.row])
    return heightVal!.height + 8 //ADDING EXTRA SPACE
}

UITableViewCell

class TblTableViewCell: UITableViewCell {
    @IBOutlet weak var txtVw: UITextView!
    @IBOutlet weak var txtVwWidthConst: NSLayoutConstraint!
    // TEXTVIEW WIDTH CONSTRAINTS    

    override func awakeFromNib() {
       super.awakeFromNib()
    }
}

Output