I'm wondering how I can use a UIButton action function to be able to press a button so each time it is pressed, a new row in a UITableView is added. Does anyone know how to accomplish that?
You have to set an IBOutlet for your UITableView.
In the IBAction of the UIButton, add a value to the data structure you used to implement the cells of the tableview.
Then call reloadData() function for the tableview outlet
That is, in code
#IBOutlet weak var table: UITableView!
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
cell?.textLabel = dataStructure[indexPath.row]
return cell
}
For the IBAction
#IBAction func buttonPressed(_ sender: UIButton)
{
dataStructure.append(someNewValue); // someNewValue is the new Value for the row
table.reloadData()
}
Related
This question already has answers here:
UIButton action in table view cell
(11 answers)
Closed 3 years ago.
I want to navigate from UITableViewCell(Xib) to UIViewController but when I try to use present Value of type 'TableViewCell' has no member 'present
So if anyone is familiar with a function that can help me navigate please help me :) .
Thank you for your time
UITableViewCell can’t present viewcontroller. Please store viewController to variable in your tableview cell. And use it to present.
Or use didSelectRowAt delegate function and using self to present ( Or write your custom cell delegate if your event fire by button in cell)
Conform your ViewController to UITableViewDelegate protocol and then in your ViewController code use the delegate method: func tableView(UITableView, didSelectRowAt: IndexPath) and inside this method perform/present a segue or any other type of navigation you have.
import UIKit
class ViewController: UIViewController, UITableViewDelegate {
override func viewDidLoad() {
super.viewDidLoad()
}
func tableView(UITableView, didSelectRowAt: IndexPath) {
// navigation logic here
}
}
Use closure inside your custom UITableViewCell to handle this scenario.
In your custom UITableViewCell create a handler and call it when the button is tapped inside the cell, i.e.
class CustomCell: UITableViewCell {
var handler: (()->())?
#IBAction func onTapButton(_ sender: UIButton) {
handler?()
}
}
Now, set the handler in cellForRowAt when creating the cell, i.e.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! CustomCell
cell.handler = {
//present your controller here...
}
return cell
}
I am new to programming and currently working on a newsfeed like app. I had a normal Table view up and running fine, but want to try it now with a costume cell type. So I created one and thought connecting the labels the usual way would be perfectly fine, but I was wrong. So I am wondering how I can let my Text label connect to my view controller, so I can use my custom cell.
class ViewController: BaseViewController, UITableViewDelegate, UITableViewDataSource {
#IBOutlet var newsfeedTableView: UITableView!
var ref: DatabaseReference!
var posts = [String]()
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return (posts.count)
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: UITableViewCell.CellStyle.default, reuseIdentifier: "cell")
//here is where I need the custom label to get the posts
cell.textLabel?.text = posts[indexPath.row]
cell.textLabel?.font = UIFont.boldSystemFont(ofSize: 18.0)
return cell
}
}
Create subclass of UITableViewCell and connect IBOutlets to this class
class YourCell: UITableViewCell {
#IBOutlet weak var customLabel: UILabel!
...
}
don't forget to set class of your prototype cell in storyboard:
then in cellForRowAt data source method downcast your dequeued cell as YourCell
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! YourCell
then you have access to YourCell outlets
cell.customLabel.text = "SomeText"
...
I'm assuming that you are using Storyboard.
First of all, you should understand that there is little difference when you use own custom table cell. In that case, in the method "cellForRowAtIndexPath", after dequeue your cell, you just have to typecast table cell like 'as! YourCustomTableCellClass'. After this line, you can access each property of this class.
First, design your table cell on Storyboard whatever you want.
Now, make a subclass of UITableViewCell and assign this class to your prototype custom cell which you have designed on Storyboard. Also, don't forget to set "reuse identifier in Storyboard table cell.
Then connect your outlets with custom cell class from Storyboard.
Now you can use code like this:
class YourTableCellClass: UITableViewCell {
// I'm using these outlets as a sample, but you have to connect them from Storyboard.
var leftTextLabel: UILabel!
var rightTextLabel: UILabel!
}
class YourTableController: UITableViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
// MARK: - TableView Delegate & DataSource
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1 // return your number of rows here...
}
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 100 // return the height for the row here.....or you can set height from Storyboard if you have fix height of all rows.
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "CellIdentifier", for: indexPath) as! YourTableCellClass
cell.leftTextLabel.text = "Text" // Set text here....
cell.rightTextLabel.text = "Text" // Set text here....
return cell
}
}
I'm trying to make two different buttons for each cell that I create in my table view. One of the buttons is a + button that will increment a label. In my testing however I cannot get the function to work. My current error says
Argument of #selector does not refer to an '#objc' method, property, or initializer
I feel like I'm implementing the .addTarget method completely wrong but I am new. Here is my code:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let item = items[indexPath.section]
let cell = tableView.dequeueReusableCell(withIdentifier: "itemCell") as! AddItemCell
cell.setCell(item: item)
let itemAmount = cell.itemAmount as UILabel?
cell.addButton.addTarget(self, action: #selector(addItem(sender:cell.addButton,forLabel:itemAmount!)), for: .touchUpInside)
}
#objc func addItem(sender: UIButton, forLabel label:UILabel) {
print("Add Button Clicked")
}
You are using selector syntax incorrectly:
action: #selector(addItem(sender:cell.addButton,forLabel:itemAmount!))
Just say:
action: #selector(addItem)
Then, however, you will face a new problem. You think that somehow you can cause this button to call something called addItem(sender:forLabel:). You can't. Change the declaration of addItem to addItem(_ sender:UIButton). That is the only kind of function a button tap can call.
You will thus have the sender (the button), but you must figure out from there what the label is. (And this should be easy, because, knowing the button, you know the cell, and knowing the cell, you know the label.) You cannot pass the label as a parameter in response to the button tap — but you don't need to.
You need to create callback function in you cell
class AddItemCell: UITableViewCell {
var buttonClickCallback:(() -> Void)?
#IBAction func onButtonClick(_ sender:Any) {
buttonClickCallback?()
}
}
and assign buttonClickCallback in tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell method
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let item = items[indexPath.section]
let cell = tableView.dequeueReusableCell(withIdentifier: "itemCell") as! AddItemCell
cell.setCell(item: item)
let itemAmount = cell.itemAmount as UILabel?
cell.buttonClickCallback = {
self.addItem(sender:cell.addButton,forLabel:itemAmount!)
}
}
I am trying to use a Table View with cell inside of UIViewController and I want each row to have a button in it. The reason I am using UIViewController instead of UITableView is because I want to have other stuff in that view instead of the whole screen taken by table view.
problem I am having is I only see one button in the last cell. How I can fix this so each row has button in it?
I was hoping that could use something like this
import UIKit
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
#IBOutlet weak var logButton: UIButton!
#IBOutlet weak var mytableView: UITableView!
let carLocations = ["Row One", "Row Two", "Row Three"]
override func viewDidLoad() {
super.viewDidLoad()
mytableView.dataSource = self
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return carLocations.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let myCell: UITableViewCell = mytableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
myCell.textLabel?.text = carLocations[indexPath.row]
myCell.detailTextLabel?.text = " Detailed text"
logButton.tag = indexPath.row
// I was hoping that I could use something like this
// myCell.logButton.tag = indexPath.row
return myCell
}
func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
if (editingStyle == UITableViewCellEditingStyle.Delete) {
// handle delete (by removing the data from your array and updating the tableview)
}
}
}
You can use Custom Cell this way.
Create a new swift file with subclass of UITableViewCell.
Assign that class to your cell by selecting your cell and go to Identity Inspector and it will look a like:
And add elements into your cell which you need for example I have added two labels and one button into cell as per your need and cell will look like:
After that connect outlet of that element into your custom call and your Custom tableview cell class will be:
import UIKit
class TableViewCell: UITableViewCell {
#IBOutlet weak var titleLbl: UILabel!
#IBOutlet weak var DetailLabel: UILabel!
#IBOutlet weak var btn: UIButton!
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
}
Now you can create a custom cell with custom tableview cell class this way in your cellForRowAtIndexPath method:
let myCell = mytableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! TableViewCell
And you can assign values to it this way:
myCell.titleLbl.text = carLocations[indexPath.row]
myCell.DetailLabel.text = "Detailed Text"
myCell.btn.tag = indexPath.row
And final code will be:
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let myCell = mytableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! TableViewCell
myCell.titleLbl.text = carLocations[indexPath.row]
myCell.DetailLabel.text = "Detailed Text"
myCell.btn.tag = indexPath.row
return myCell
}
And your result will be:
Check this sample for more Info.
Drop a UITableViewCell on your tableview. That will give you option to customize your cell's look and feel. Create a new class inheriting from UITableViewCell and add that as a class to your tableview cell. Create outlets from cell to this new file and then use cellForRowAtIndexPath to set the properties of the controls inside your cell.
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! CBTableViewCell
// add self as delegate for tablecell so delegate can call the function defined within
cell.delegate = self
cell.title.text = self.items[indexPath.row]
return cell
}
I would use Custom Cells to solve this problem...
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell:CustomCell = tableView.dequeueReusableCellWithIdentifier("CustomCell") as! CustomCell
//Do sth
return cell
}
Your cell:
import UIKit
class CustomCell: UITableViewCell {
#IBOutlet var Button: UIButton!
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func awakeFromNib() {
super.awakeFromNib()
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
}
}
Actually it is very easy: You just drag a UITableView into your view in the size you want. You add a prototype cell to it and then you customise that cell by dragging in labels, etc. You make a new class, which inherits from that UITableViewCell as explained earlier. You also connect the labels and buttons to the class as explained i the other answers. Apple has a very good explanation here Go to the section where they explain how to customise the cell.
I have a strange issue with my tableView.
I have a List of audio tracks and a segue to an audio player in order to play the selected track at a specific row. Everything works fine!
I wanted to change the background color for the selected row in the table so that, once the user play the audio and come back to the list of tracks (my Table View Controller) , he can see which are the previously selected rows.
But when I run It change me the color not only for the row at index path I selected but also to the item at index path + 10.
If I select the First Row it change me the color for the row at the index: 0, 10, 20, 30...
In order to change the color of the selected cell I did the follow:
// MARK: - Navigation
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
self.performSegueWithIdentifier("audioPlayer", sender: tableView)
var selectedCell:UITableViewCell = tableView.cellForRowAtIndexPath(indexPath) as CustomTableViewCell
selectedCell.contentView.backgroundColor = UIColor.greenColor()
selectedCell.backgroundColor = UIColor.blueColor()
Please find a screenshot of my issue, I have selected just three rows: 1, 3, 5 but I get selected 1,3,5,11,13,15,21,23 and so on... :
https://www.dropbox.com/s/bhymu6q05l7tex7/problemaCelleColore.PNG?dl=0
For further details - if can help - here it is my Custom Table View class:
import UIKit
class CustomTableViewCell: UITableViewCell {
#IBOutlet weak var artista: UILabel!
#IBOutlet weak var brano: UILabel!
var ascoltato = false
#IBOutlet weak var labelRiproduciAscoltato: UILabel!
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
func setCell(artista: String, brano: String){
self.artista.text = artista
self.brano.text = brano
}
} // END MY CUSTOM TABLE VIEW CELL
Here it is the method cellForRowAtIndexPath in my TableViewController:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = self.tableView.dequeueReusableCellWithIdentifier("tableCell", forIndexPath: indexPath) as CustomTableViewCell
var tracks : Brani //Brani is my custom Object for handle my tracks
cell.setCell(tracks.title!, brano: tracks.author!)
return cell
}
I am running on iPad Air with iOS 7.1.
Thank you in advance for any suggestion or advice related to my issue.
This is probably because UITableViewCells are recycled. This means the formerly selected tableViewCell gets reused by the cells at the lower indexes. This is expected behavior of a UITableView and makes sense, as it saves memory usage. To fix the issue, you will need to have your datasource keep a track of which cell is selected, and updated the cell's background color accordingly.
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
self.performSegueWithIdentifier("audioPlayer", sender: tableView)
//datasource is updated with selected state
//cell is updated with color change
}
Then in your cellForRowAtIndexPath method:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = self.tableView.dequeueReusableCellWithIdentifier("tableCell", forIndexPath: indexPath) as CustomTableViewCell
var tracks : Brani //Brani is my custom Object for handle my tracks
cell.setCell(tracks.title!, brano: tracks.author!)
//update cell style here as well (by checking the datasource for selected or not).
return cell
}