I put my working tableviewcontroller inside a pageviewcontroller. Now I have to register the cell in the tableview programmatically and the method awakeFromNib is not called for the cell. All properties in my custom cell are not initialized and the app crashes if I try to set content.
Is there anything different when I add a tableviewcontroller in a pageviewcontroller?
self.tableView.registerClass(ParticipantCell.self, forCellReuseIdentifier: ParticipantCell.cellIdentifier)
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let index = self.sections[indexPath.section].index+indexPath.row
let participant = self.participants[index]
let cell = tableView.dequeueReusableCellWithIdentifier(ParticipantCell.cellIdentifier, forIndexPath: indexPath) as! ParticipantCell
// cell.setParticipantData(participant)
return cell
}
If you are creating cells programmatically awakeFromNib is not called. However you can do your configurations by overriding:
init(style: UITableViewCellStyle, reuseIdentifier: String?)
As a suggestion you can have a method like this:
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
setupCell()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setupCell()
}
func setupCell() {
// setup your cell here
}
The problem was that the Tableviewcontroller was instantiated wrong. I solved it by instantiating it from the storyboard:
let storyboard = UIStoryboard(name: "Participants", bundle: NSBundle.mainBundle())
if let controller = storyboard.instantiateViewControllerWithIdentifier("ParticipantListController") as? ParticipantListController{
...
}
Related
I try use UITableViewCell. My custom cell has StackView's and other views.
I need to send object from controller (UITableViewController) for next parsing it.
in cell I set field:
class MyCell: UITableViewCell {
var myObject : MyObject?
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
in this I try get data from my object
}
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
}
and in my Controller I write:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// create a new cell if needed or reuse an old one
let cell = self.tableView.dequeueReusableCell(withIdentifier: cellReuseIdentifier) as MyCustomCell!
cell.myObject = self.arrayMyObjects[indexPath.row]
return cell
}
But everytime I have nil in my cell. Why?
In your cell init is to early to try and access myObject. You should use a didSet on the property to make the changes when it's assigned a new value.
var myObject : MyObject? {
didSet {
// Update your subviews here.
}
}
I have a two custom cells implemented:
class TextFieldCell: UITableViewCell{
var label = UILabel()
var textField = UITextField()
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
label.text = "Name"
textField.placeholder = "Enter Task Name Here"
addSubview(label)
addSubview(textField)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
class SwitchCell : UITableViewCell {
var label = UILabel()
var switchControl = UISwitch()
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
label.text = "State"
switchControl.on = true
addSubview(label)
addSubview(switchControl)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
In my table view class i have declared this two cells:
let textFieldCell = TextFieldCell(style: .Default, reuseIdentifier: "textFieldCell")
let switchCell = SwitchCell(style: .Default, reuseIdentifier: "switchCell")
and have delegate method in it:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
switch indexPath.row {
case 0: return textFieldCell
case 1: return switchCell
default: return UITableViewCell()
}
}
But when table view loads i've see only switch control on the left of second row. I don't know why.
Try this:
private let reuseIdentifier = "switchCell"
//identifier of your cell.
Seems you have missed registering the cell.
let tableNib = UINib(nibName:"SwitchCell", bundle:nil)
self.tableView!.registerNib(tableNib,forCellReuseIdentifier:reuseIdentifier)
TextFieldCell Added below Code in ViewDidLoad of TableViewCell
self.tableView.registerClass(SwitchCell, forCellReuseIdentifier: "switchCell")
self.tableView.registerClass(TextFieldCell, forCellReuseIdentifier: "textFieldCell")
[UITableViewCell] <- [genericCell] <- [Cell1], [Cell2], [Cell3]
Hello. Please imagine hierarchy above. In my code I don't have objects exactly of type genericCell, but this class shares some properties.
What design of inits should be in my code? I have following structure for genericCell:
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
//my stuff (initializing shared properties)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
But what about Cell1? How can I invoke init(style: UITableViewCellStyle, reuseIdentifier: String?) in genericCell for "my stuff" operations through initialisation of Cell1 instance? Now they doesn't perform.
EDIT
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let typeOfCell = FbDataManager.sharedInstance.posts[indexPath.row][FbDataManager.sharedInstance.typeParameter] as! String
switch typeOfCell {
case self.linkTypeOfPost:
var cell = tableView.dequeueReusableCellWithIdentifier(self.linkCellIdentifier) as? FbLinkPostViewCell
if cell == nil {
cell = FbLinkPostViewCell.init(style: .Default, reuseIdentifier: self.linkCellIdentifier)
}
//...
Hi again. This is part from tableView's delegate, btw I copy-pasted Abhinav's inits to my code and again those inits aren't working. (no output to console)
I'm not sure I understand your question correctly, but it seems to be about inheritance between classes. So basically you have a "GenericCell" class that inherits from "UITableViewCell", and "CellOne", "CellTwo", and "CellThree" classes that each inherit from "GenericCell". If you want to go through init with style, one way to set this up would be like this:
class GenericCell: UITableViewCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
// code common to all your cells goes here
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
class CellOne: GenericCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier) // the common code is executed in this super call
// code unique to CellOne goes here
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
You could then create instances of CellOne in your table view's data source like so:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCellWithIdentifier("cell")
if (cell == nil) {
cell = CellOne.init(style: .Default, reuseIdentifier: "cell")
}
return cell!
}
For each instance it will now first go through the common setup done in "GenericCell", and then through the unique setup in "CellOne". "CellTwo" and "CellThree" would be set up accordingly.
EDIT
A more concrete example of how to configure instances of all three Cell types:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
// you need to write a method like this to figure out which type you need:
let cellID = self.cellIDForIndexPath(indexPath) // returns either "cell1", "cell2" or "cell3"
// dequeue or init a cell of the approriate type
var cell = tableView.dequeueReusableCellWithIdentifier(cellID)
if (cell == nil) {
switch cellID {
case "cell1": cell = CellOne.init(style: .Default, reuseIdentifier: "cell")
case "cell2": cell = CellTwo.init(style: .Default, reuseIdentifier: "cell")
case "cell3": cell = CellThree.init(style: .Default, reuseIdentifier: "cell")
default: cell = UITableViewCell()
}
}
// configure the individual cell if needed (you need to implement methods + logic here that fit your data)
(cell as! GenericCell).configureForData(self.dataForIndexPath(indexPath))
return cell!
}
This is how I would lay down the hierarchy mentioned by you:
Step 1 : Make Generic Cell class
class GenericCell : UITableViewCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
print("Generic Cell Initialization Done")
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
Step 2 : Make Specific Cell 1 class:
class MyCell1 : GenericCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
print("MyCell1 Initialization Done")
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
Step 3 : Make Specific Cell 2 class:
class MyCell2 : GenericCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
print("MyCell2 Initialization Done")
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
Step 4 : Make Specific Cell 3 class:
class MyCell3 : GenericCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
print("MyCell3 Initialization Done")
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
Step 5 : Finally use the cells like this:
let cell1 = MyCell1.init(style: UITableViewCellStyle.Default, reuseIdentifier: "cell1")
let cell2 = MyCell2.init(style: UITableViewCellStyle.Default, reuseIdentifier: "cell2")
let cell3 = MyCell3.init(style: UITableViewCellStyle.Default, reuseIdentifier: "cell3")
PS: This would guarantee setting the properties in generic cell as well in specific cells.
EDIT: This is how you would use cells in cellForRowAtIndexPath:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
if indexPath.section == 0 {
let cell1 = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as MyCell1
if cell1 == nil {
cell1 = MyCell1.init(style: UITableViewCellStyle.Default, reuseIdentifier: "cell1")
}
// Do your cell property setting
return cell1
} else if indexPath.section == 1 {
let cell2 = tableView.dequeueReusableCellWithIdentifier("cell2", forIndexPath: indexPath) as MyCell2
if cell2 == nil {
cell2 = MyCell2.init(style: UITableViewCellStyle.Default, reuseIdentifier: "cell2")
}
// Do your cell property setting
return cell2
} else {
let cell3 = tableView.dequeueReusableCellWithIdentifier("cell3", forIndexPath: indexPath) as MyCell3
if cell3 == nil {
cell3 = MyCell3.init(style: UITableViewCellStyle.Default, reuseIdentifier: "cell3")
}
// Do your cell property setting
return cell3
}
}
I am currently learning Swift programatically. I am wanting to add a tableView to a viewController (for the purpose of being able to manipulate the constraints later) and customize the cells with a TableViewCell.
I can do this with my eyes closed when using the storyboard, but when I try to do it with just straight code I have empty cells.
My storyboard is comprised of one (1) empty viewController that has the custom class of ViewController
I have looked at others with similar issues but non of the solutions have worked. Would love to know what I am overlooking (probably something simple). Thanks in advance for the help!
ViewController.swift:
import UIKit
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource{
var tableView: UITableView = UITableView()
var items: [String] = ["Viper", "X", "Games"]
override func viewDidLoad() {
tableView.frame = CGRectMake(0, 0, view.frame.size.width, view.frame.size.height)
tableView.delegate = self
tableView.dataSource = self
tableView.registerClass(TableViewCell.self, forCellReuseIdentifier: "cell")
self.view.addSubview(tableView)
}
func tableView(tableView:UITableView, heightForRowAtIndexPath indexPath:NSIndexPath)->CGFloat
{
return 50
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return self.items.count
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 3
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! TableViewCell
//cell.textLabel?.text = self.items[indexPath.row]
cell.companyName.text = "name"
return cell
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
TableViewCell:
import UIKit
class TableViewCell: UITableViewCell {
var companyName = UILabel()
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
companyName.frame = CGRectMake(0, 0, 200, 20)
companyName.translatesAutoresizingMaskIntoConstraints = false
contentView.addSubview(companyName)
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
}
Hello #Michael First thing is you should only use awakeFromNib when you are using a .xib(Nib) and in your case you are using custom class without such xib so, you should use
override init(style: UITableViewCellStyle, reuseIdentifier: String?){
super.init(style: style, reuseIdentifier: reuseIdentifier)
companyName = UILabel(frame: CGRectMake(0, 0, 200, 20))
contentView.addSubview(companyName)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
also you should initialise your label before using it.
this will solve your problem.
Read apple's documentation for subclassing UITableViewCell here.
If you want your custom cell to load from some custom xib you do sometimes like:
tableView.registerNib(UINib(nibName: "CustomTableViewCell", bundle: NSBundle.mainBundle()), forCellReuseIdentifier: "CustomTableViewCell")
And you should have CustomTableViewCell.xib file where you have table view cell with reuse identifier CustomTableViewCell
Checkout how your cell's companyLabel is laid out. Does it exist or no?
In your code, I replaced companyLabel with default textLabel and it worked for me.
cell.textLabel!.text = self.items[indexPath.row]
I think awakeFromNib is not called because you do not register a nib but a class. Try this instead:
class TableViewCell: UITableViewCell {
let companyName = UILabel()
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
// Initialization code
companyName.frame = CGRectMake(0, 0, 200, 20)
companyName.translatesAutoresizingMaskIntoConstraints = false
contentView.addSubview(companyName)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
I am using custom cocoa class extends from TableViewCell and it doesn't give any error message but the cells do not appear in the tableview. The scroll gets longer but the table cells are not viewable.
I typed this in my ViewController :
tableView.registerClass(CustomTableViewCell.self, forCellReuseIdentifier: "Cell")
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath)->UITableViewCell
{
var cell:CustomTableViewCell? = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as? CustomTableViewCell
if cell == nil {
cell = CustomTableViewCell(style: UITableViewCellStyle.Default, reuseIdentifier: "Cell")
}
cell!.labTime.text = filtered[indexPath.row].name!
return cell!
}
and my cell class looks like
var labTime = UILabel()
override func awakeFromNib() {
// Initialization code
super.awakeFromNib()
labTime = UILabel(frame: contentView.bounds)
labTime.font = UIFont(name:"HelveticaNeue-Bold", size: 16)
contentView.addSubview(labTime)
}
I don't use any storyBoard or xib file.
Can not find the solution,
thanks
Do this way.
All view intialization of properties should go in init method.
Add this in your custom cell class
var labTime: UILabel!
required init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override init(style: UITableViewCellStyle, reuseIdentifier: String!) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
//Do your cell set up
labTime = UILabel(frame: contentView.bounds)
labTime.font = UIFont(name:"HelveticaNeue-Bold", size: 16)
contentView.addSubview(labTime)
}
Add the below line in viewDidLoad method of your view controller.
tableView.registerClass(CustomTableViewCell.self, forCellReuseIdentifier: "Cell")
Set these two delegate - UITableViewDataSource and UITableViewDelegate