This is not duplicated question, because there is not real solution fo this issue
I am trying implement UITableViewcell dynamic height by its content using constraint, but getting layout warning:
Will attempt to recover by breaking constraint
Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger. The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in may also be helpful. 2019-03-15 12:27:52.085475+0400 TableCellDynamicHeight[31984:1295380] [LayoutConstraints] Unable to simultaneously satisfy constraints. Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. ( "", "", "", "" )
I checked some threads: Dynamic tableViewCell height
Dynamic Height Issue for UITableView Cells (Swift)
Swift 3 - Custom TableViewCell dynamic height - programatically
What is correct solution, what am I missing?
ViewController:
import UIKit
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
lazy var tableView: UITableView = {
let table = UITableView()
table.backgroundColor = .white
table.translatesAutoresizingMaskIntoConstraints = false
table.register(TableViewCell.self, forCellReuseIdentifier: "cellId")
table.dataSource = self
table.delegate = self
return table
}()
let arr:[Int:UIColor] = [345: UIColor.random, 422: .random, 23: .random, 344: .random,200: .random,140: .random]
var pickerDataVisitLocation = [203: "Home", 204: "Hospital", 205: "Other"]
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .red
self.view.addSubview(tableView)
//
tableView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor).isActive = true
tableView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor).isActive = true
tableView.topAnchor.constraint(equalTo: self.view.topAnchor).isActive = true
tableView.bottomAnchor.constraint(equalTo: self.view.bottomAnchor).isActive = true
tableView.tableFooterView = UIView()
}
}
extension ViewController {
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return arr.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellId", for: indexPath) as! TableViewCell
let value:UIColor = Array(arr)[indexPath.row].value
let key = Array(arr)[indexPath.row].key
cell.setupViews(he: CGFloat(key), color: value)
return cell
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return UITableView.automaticDimension
}
func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
return UITableView.automaticDimension
}
}
extension UIColor {
static var random: UIColor {
return UIColor(red: .random(in: 0...1),
green: .random(in: 0...1),
blue: .random(in: 0...1),
alpha: 1.0)
}
}
TableViewCell:
import UIKit
class TableViewCell: UITableViewCell {
override func awakeFromNib() {
super.awakeFromNib()
}
override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
func setupViews(he:CGFloat, color:UIColor) {
let v:UIView = UIView()
v.translatesAutoresizingMaskIntoConstraints = false
self.addSubview(v)
v.trailingAnchor.constraint(equalTo: self.trailingAnchor).isActive = true
v.backgroundColor = color
v.leadingAnchor.constraint(equalTo: self.leadingAnchor).isActive = true
v.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
v.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
v.heightAnchor.constraint(equalToConstant: he).isActive = true
#warning("here is constraint error conflict with bottomAnchor and heightAnchor, need correct solution")
}
}
You're doing a couple things wrong...
First, cells are reused (hence the dequeueReusableCell), but your setupViews() func is adding a new subview every time a cell is reused.
That means as you scroll, and the cells are reused, you end up with 2, 3, 4 ... a dozen subviews, all with conflicting constraints.
Move your addSubview() to a common initialization func in your cell, so the view is only created and added once.
That's also where you should setup your constraints.
To change the height of the subview as your app is designed, you want to change the .constant on the height constraint of the subview.
Here is your modified code. I've added enough comments in the code that it should be clear:
class HattoriTableViewCell: UITableViewCell {
// the view to add as a subview
let myView: UIView = {
let v = UIView()
v.translatesAutoresizingMaskIntoConstraints = false
return v
}()
// the constraint we'll use for myView's height
var myViewHeightConstraint: NSLayoutConstraint!
override func awakeFromNib() {
super.awakeFromNib()
commonInit()
}
override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
commonInit()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
commonInit()
}
func commonInit() -> Void {
// add the subview
self.addSubview(myView)
// constrain it to all 4 sides
myView.trailingAnchor.constraint(equalTo: self.trailingAnchor).isActive = true
myView.leadingAnchor.constraint(equalTo: self.leadingAnchor).isActive = true
myView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
myView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
// create the height constraint
myViewHeightConstraint = myView.heightAnchor.constraint(equalToConstant: 1)
// needs Priority less-than 1000 (default) to avoid breaking constraints
myViewHeightConstraint.priority = UILayoutPriority.init(999)
// activate it
myViewHeightConstraint.isActive = true
}
func setupViews(he:CGFloat, color:UIColor) {
// set myView's background color
myView.backgroundColor = color
// change myView's height constraint constant
myViewHeightConstraint.constant = he
}
}
class HattoriViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
lazy var tableView: UITableView = {
let table = UITableView()
table.backgroundColor = .white
table.translatesAutoresizingMaskIntoConstraints = false
table.register(HattoriTableViewCell.self, forCellReuseIdentifier: "cellId")
table.dataSource = self
table.delegate = self
return table
}()
let arr:[Int:UIColor] = [345: UIColor.random, 422: .random, 23: .random, 344: .random,200: .random,140: .random]
var pickerDataVisitLocation = [203: "Home", 204: "Hospital", 205: "Other"]
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .red
self.view.addSubview(tableView)
//
tableView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor).isActive = true
tableView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor).isActive = true
tableView.topAnchor.constraint(equalTo: self.view.topAnchor).isActive = true
tableView.bottomAnchor.constraint(equalTo: self.view.bottomAnchor).isActive = true
tableView.tableFooterView = UIView()
// use a reasonable value -- such as the average of what you expect (if known)
tableView.estimatedRowHeight = 200
}
}
extension HattoriViewController {
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return arr.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellId", for: indexPath) as! HattoriTableViewCell
let value:UIColor = Array(arr)[indexPath.row].value
let key = Array(arr)[indexPath.row].key
cell.setupViews(he: CGFloat(key), color: value)
return cell
}
// NOT NEEDED
// func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
// return UITableView.automaticDimension
// }
//
// func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
// return UITableView.automaticDimension
// }
}
extension UIColor {
static var random: UIColor {
return UIColor(red: .random(in: 0...1),
green: .random(in: 0...1),
blue: .random(in: 0...1),
alpha: 1.0)
}
}