how can I get tableview label value on button click in swift - ios

I am new in swift and I want to get the value of label from tableview on button click
I am using code like this but it is getting crash
in cellforrowatindexpath
cell.btnsubmit.tag = indexPath.row
cell.btnsubmit.addTarget(self, action: #selector(buttonSelected), for: .touchUpInside)
#objc func buttonSelected(sender: UIButton){
print(sender.tag)
let cell = sender.superview?.superview as! PatientUpdateVCCell
surgery_date = cell.surgeryDateTextField.text!
discharge_date = cell.dischargeDateTextField.text!
follow_up_duration = cell.lblfolowup.text!
follow_up_date = cell.firstFollowUpTextField.text!
patient_status = cell.patientStatusTextView.text!
}
but it is getting crash. How can I achieve this
crash
Could not cast value of type 'UITableViewCellContentView' (0x11a794af0) to 'appname.PatientUpdateVCCell' (0x10ae74ae0).

According to your crash last superView is contentView then it's superView is the needed cell , so You need
let cell = sender.superview!.superview!.superview as! PatientUpdateVCCell

Target/action is pretty objective-c-ish. And view hierarchy math is pretty cumbersome.
A swiftier way is a callback closure which is called in the cell and passes the cell.
In the cell add a callback property and an IBAction. Connect the action to the button
var callback : ((UITableViewCell) -> Void)?
#IBAction func buttonSelected(_ sender: UIButton) {
callback?(self)
}
In cellForRow rather than the tag assign the closure
cell.callback = { currentCell in
self.surgery_date = currentCell.surgeryDateTextField.text!
self.discharge_date = currentCell.dischargeDateTextField.text!
self.follow_up_duration = currentCell.lblfolowup.text!
self.follow_up_date = currentCell.firstFollowUpTextField.text!
self.patient_status = currentCell.patientStatusTextView.text!
}
And delete the action method in the controller

Related

Reloading the collectionView after delete

I'm using firebase. My code works but my issue is when I press the accept button, I want that index to be deleted from the collectionView and I want the table to reload right away right after. I can't use the slide to delete because I need it for another function.
This is in my cell class thats why I did not use self. to call the collectionView. This function is being called by a addTarget() method. I'm thinking maybe passing an indexPath as a parameter, but I don't know how to pass an indexPath.item as a parameter and also how to pass a parameter inside an addTarget() method.
func handleAccept(_ sender: UIButton) {
print("button pressed")
guard let artId = art?.artId else {return}
let approvedRef =
FIRDatabase.database().reference().child("approved_art")
approvedRef.updateChildValues([artId: 1])
let pendingRef =
FIRDatabase.database().reference().child("pending_art").child("\(artId)")
pendingRef.removeValue { (error, ref) in
if error != nil {
return
}
let layout = UICollectionViewFlowLayout()
let pendingArtCollectionViewController =
PendingArtsCollectionViewController(collectionViewLayout: layout)
DispatchQueue.main.async {
pendingArtCollectionViewController.collectionView?.reloadData()
}
}
}
You don't need to pass indexpath as argument, you can get the indexpath of the tableView in button action with the following code :
func handleAccept(_ sender: UIButton) {
let center = sender.center
let rootViewPoint = sender.superview!!.convert(center!, to: self.myTableView)
let currentIndexpath = myTableView.indexPathForRow(at: rootViewPoint)
}

Adding an observer to a UISwitch within a custom tableview cell

This is a follow on from a previous question I have asked but I feel I am missing something very simple and its driving me up the wall!
I have a custom tableview cell which contains a switch and I need to trigger a function each time it's value is changed. I've tried using .addTarget but it never seems to trigger the function so maybe my selector syntax is incorrect.
I create the switch programatically within the tableview cell like this:
let thisSwitch: UISwitch = {
let thisSwitch = UISwitch()
thisSwitch.isOn = false
thisSwitch.translatesAutoresizingMaskIntoConstraints = false
thisSwitch.addTarget(self, action: Selector("switchTriggered:"), for: .valueChanged)
return thisSwitch
}()
Then directly below that I have my function:
func switchTriggered(sender: AnyObject) {
print("SWITCH TRIGGERED")
let sentSwitch = sender as! UISwitch
privateExercise.switchState = sentSwitch.isOn
}
It shows an error message stating " No method declared with Objective-C selector 'switchTriggered:' ". What am I missing here? Any help would be much appreciated!
The selector syntax should be
thisSwitch.addTarget(self, action: #selector(switchTriggered), for: .valueChanged)
Also keep the parameter as UISwitch type itself in order to avoid casting in function
func switchTriggered(sentSwitch: UISwitch) {
print("SWITCH TRIGGERED")
privateExercise.switchState = sentSwitch.isOn
}

How to pass value on UIButton click to delegate inside collectionViewCell?

I am learning iOS programming for last few days, so I am new to this tech. I am building simple app where I'm using collection view which has EventCell inside it. Each EventCell has one UIButton and EventCell has uniq value(ID coming from JOSN API response). I need to pass that value to delegate which call new ViewController. I have setup the delegate method which is working correctly, just finding the solution for how to pass value on button click
PS: I am not using storyboard
**EventCell.swift**
lazy var leaderboardButton: UIButton = {
let leaderboardBtn = UIButton(type: .system)
leaderboardBtn.setTitle("LeaderBoard", for: .normal)
leaderboardBtn.addTarget(self, action: #selector(handleLeaderBoardClick), for: .touchUpInside)
leaderboardBtn.tintColor = .white
return leaderboardBtn
}()
weak var delegate: HomeControllerDelegate?
func handleLeaderBoardClick() {
// need to get uniq value and pass here....
delegate?.clickOnLeaderBoard()
}
If you need to pass that ID value to delegate object which is in your case is your ViewController - then you need to modify clickOnLeaderboard function from the HomeControllerDelegate protocol.
Modify it and pass your EventCell's ID as an additional argument to it.
delegate?.clickOnLeaderBoard(cellID)
Also, don't forget to update function signature in view controller class.
In func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) overload
add this:
cell.yourButton.tag = indexPath.row
cell.yourButton.addTarget(self, action: #selector(buttonClicked(sender:)), for: .touchUpInside)
you should have buttonClicked(sender:) in your UIViewController.
buttonClicked(sender:){
tag = sender.tag
// you can use this tag to change your view controller
}
Change your function to include a parameter:
func handleLeaderBoardClick(_ sender: UIButton) {
// need to get uniq value and pass here....
delegate?.clickOnLeaderBoard()
}
Update the selector:
leaderboardBtn.addTarget(self, action: #selector(handleLeaderBoardClick(_:)), for: .touchUpInside)
Now you can perform a comparison between sender and leaderboardButton to see if they're the same.

how can I refresh a single button in UITableViewCell instead of refreshing whole table or whole cell?

In my swift app I have a UITableView with one static cell and many dynamic cells.
Static cell contains different fields, such as labels, map (taken from MapKit) and a button, that indicates whether user voted up or not.
Now, when user presses the button, I want to change its color, possibly without refreshing anything else.
So far my code looks like this:
var currentUserVote:Int = 0
func tableView(_ tview: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if (indexPath as NSIndexPath).row == 0 {
let cell = tview.dequeueReusableCell(withIdentifier: "cellStatic") as! VideoDetailsCell
fetchScore(cell.score)
let voteUpImage = UIImage(named: "voteUp");
let tintedVoteUpImage = voteUpImage?.withRenderingMode(UIImageRenderingMode.alwaysTemplate)
cell.voteUpButton.setImage(tintedVoteUpImage, for: UIControlState())
checkUsersVote() { responseObject in
if(responseObject == 1) {
cell.voteUpButton.tintColor = orangeColor
} else if (responseObject == -1){
cell.voteUpButton.tintColor = greyColor
} else {
cell.voteUpButton.tintColor = greyColor
}
self.currentUserVote = responseObject
}
//map handling:
let regionRadius: CLLocationDistance = 1000
let initialLocation = CLLocation(latitude: latitude, longitude: longitude)
centerMapOnLocation(initialLocation, map: cell.mapView, radius: regionRadius)
//cell.mapView.isScrollEnabled = false
cell.mapView.delegate = self
.
.
.
return cell
} else {
//handle dynamic cells
}
}
So in the method above I'm checking if user voted already and based on that I'm setting different color on the button. I'm also centering the map on a specific point.
Now, since it's a static cell, I connected IBAction outlet to that button:
#IBAction func voteUpButtonAction(_ sender: AnyObject) {
if(currentUserVote == 1) {
self.vote(0)
}else if (currentUserVote == -1){
self.vote(1)
} else {
self.vote(1)
}
}
and the vote method works as follows:
func vote(_ vote: Int){
let indexPath = IndexPath(row: 0, section: 0)
let cell = tview.dequeueReusableCell(withIdentifier: "cellStatic") as! VideoDetailsCell
switch(vote) {
case 1:
cell.voteUpButton.tintColor = orangeColor
case 0:
cell.voteUpButton.tintColor = greyColor
case -1:
cell.voteUpButton.tintColor = greyColor
default:
cell.voteUpButton.tintColor = greyColor
}
tview.beginUpdates()
tview.reloadRows(at: [indexPath], with: .automatic)
tview.endUpdates()
currentUserVote = vote
//sending vote to my backend
}
My problem is, that when user taps the button, he invokes the method vote, then - based on the vote, the button changes color, but immediately after that method cellForRow is called and it changes the color of the button again. Also, it refreshes the map that's inside of it.
What I want to achieve is that when user taps the button, it should immediately change its color and that's it. Map stays untouched and the button is not changed again from cellForRow.
Is there a way of refreshing only that particular button without calling again cellForRow?
First of all, you confuse static and dynamic cells. You can use static cells only in the UITableViewController and you can't use static and dynamic cell at the same time.
I strongly recommend you not to use cell for storing map and button. All elements from the cell will be released after scrolling it beyond the screen.
I can advise you use TableViewHeaderView for this task. In this case you will be able set button and map view as #IBOutlet.
(See more about adding tableview headerView. You can also set it from interface builder.)
Another way is change tableView.contentInset and set your view with map and button as subview to tableView. This method is used when you need create Stretchy Headers.
It should be quite easy, simply do it in your button handler. The sender argument there is the button object that caused the action. When you were connecting it from IB there was a dropdown to select sender type, you may have missed it and the whole thing would have been obvious with UIButton type there.
Simply change your handler like this :
#IBAction func voteUpButtonAction(_ sender: UIButton) {
if(currentUserVote == 1) {
self.vote(0)
}else if (currentUserVote == -1){
self.vote(1)
} else {
self.vote(1)
}
sender.backgroundColor = yourFavouriteColor
}
Another approach would be to create an IBOutlet for your button, since its from a static cell, and then you would be able to reference it from any place in your view controller.
In this call:
func tableView(_ tview: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
I see it calls checkUsersVote() which I'm guessing should get the updated value set in the vote() call. Could the problem be that you aren't doing this
currentUserVote = vote
until after reloadRows() is called?

Change Element Value outside TableView Scope

i have a TableView with a customCell. I set the values of the customCell Elements inside cellForRowAtIndexPath:. No problem. But i want to change some customCell Element Values outside of the cellForRowAtIndexPath: Scope. For example after a Swipe i want to change the Value of a cell element inside my swipe function
func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
let cell:customCell = self.tableView?.dequeueReusableCellWithIdentifier("customCell")! as customCell
let rowData: NSDictionary = self.tableData[indexPath.row] as NSDictionary
let imageSwipeLeft = UISwipeGestureRecognizer(target: self, action: "imageSwiped:")
imageSwipeLeft.direction = .Left
let urlString: NSString = rowData["testImage"] as NSString
self.indexPathArray += [indexPath]
cell.testLabel.text = "Test Label"
cell.testImage.image = image
cell.testImage.tag = indexPath.row
cell.testImage.addGestureRecognizer(imageSwipeLeft)
cell.testImage.userInteractionEnabled = true
ImageLoader.sharedLoader.imageForUrl(urlString, completionHandler:{(image: UIImage?, url: String) in
cell.testImage.image = image
cell.testImage.layer.borderWidth = 6;
cell.testImage.layer.borderColor = UIColor.whiteColor().CGColor
cell.testImage.clipsToBounds = true
cell.placeholderLoading.stopAnimating()
})
return cell
}
func imageSwiped(recognizer: UISwipeGestureRecognizer) {
let testData: NSDictionary = self.tableData[recognizer.view.tag] as NSDictionary
let imageSlide = recognizer.view as UIImageView
var imageURL = testData["image"] as String
ImageLoader.sharedLoader.imageForUrl(imageURL, completionHandler:{(image: UIImage?, url: String) in
UIView.transitionWithView(imageSlide,
duration:0.44,
options: .TransitionCrossDissolve,
animations: { imageSlide.image = image },
completion: nil)
})
let indexPath = self.indexPathArray[recognizer.view.tag] as NSIndexPath
let cell = self.tableView?.cellForRowAtIndexPath(indexPath)as customCell
cell.testLabel.text = "Test"
}
UITableView follows the Model-View-Controller pattern. According to this pattern, all your changes need to be done to the model - in other words, to the data structure that stores the information from which you populate your cell data. Once you made the change to the model, you tell the view that the data has changed, which would then show the new data.
Let's say that your cellForRowAtIndexPath function reads from an array. Your imageSwiped function should then locate the item that has been swiped, modify its entry in the array, and call either reloadData or reloadRowsAtIndexPaths.
That's it! Once you notify the table view of the reload, it would go back to the array, find the modified data, and call your cellForRowAtIndexPath to display it.
Specifically, in your code add an array called swipedCells to the same class where you declared tableData array:
var swipedCells = Boolean[](count:self.tableData.count, repeatedValue: false)
Now replace
cell.testLabel.text = "Test Label"
line with
if self.swipedCells[indexPath.row] {
cell.testLabel.text = "Swiped!"
} else {
cell.testLabel.text = "Test Label"
}
Finally, change the imageSwiped as follows:
let indexPathRow = self.indexPathArray[recognizer.view.tag] as Int
self.swipedCells[indexPathRow] = true
self.tableView?.reloadData()
This way the cells that you have swiped would continue to have a label "Swiped!" even after you scroll.
Ok after a huge amount of hours :D i solved my problem.
let indexPath = self.priceObjects[recognizer.view.tag] as NSIndexPath
let cell = self.tableView?.cellForRowAtIndexPath(indexPath)as customCell
i call this inside my imageSwipe function. Inside the cellForRowAtIndexPath function where i set the initial cell element values i store the indexPath inside an array. An i tag the Images to get a Index if the Swipe Events happens. I think it is far away from the ideal way...but works for me. I hope someday someone post the good way ;) cause this is very quick n' dirty.

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