When I tap only one time on one of cell in table view, it works perfect to another view controller. But if I tap twice, triple or more times on the cell quickly before move to another view controller.
An error of array index out of range would be shown and highlighted "let labelTitle = self.resultsTitleArray[indexPath.row]". I tried to use self.view.userInteractionEnabled = false before performSegueWithIdenitifier and self.view.userInteractionEnabled = true after performSegueWithIdenitifier. But still doesn't work.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if (segue.identifier == "moreDetail"){
let viewController = segue.destinationViewController as! ProductDetailViewController
let indexPath = self.resultsTable.indexPathForSelectedRow!
let labelTitle = self.resultsTitleArray[indexPath.row]
viewController.labelTitleText = labelTitle
self.resultsTable.deselectRowAtIndexPath(indexPath, animated: true)
}
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
self.performSegueWithIdentifier("moreDetail", sender: self)
}
you need to check if indexpath is nil
if(indexPath == nil){
return
}
and to be 100% sure it works you can also do
if(indexPath == nil || indexPath.row >= self.resultsTitleArray.length){
return
}
You can disable the multiple touches from the TableView so that
those events will not be fired by setting the multipleTouchEnabled to false.
self.tableView.multipleTouchEnabled = false
Can you try removing didSelectRowAtIndexPath and going to your storyboard and Control-dragging from the cell to the segue view controller. Name that segue "moreDetail." See if the segue fires immediately before you have a chance to double- or triple-click the button.
Related
Hi I'm trying to perform a segue programmatically without the Storyboard. Currently I have this as my code:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "popOutNoteExpanded" {
let vc = segue.destination as! ExpandedCellViewController
let cell = sender as! AnnotatedPhotoCell
sourceCell = cell
vc.picture = cell.imageView.image
print("button pressed")
}
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
performSegue(withIdentifier: "popOutNoteExpanded", sender: indexPath)
}
When I click on the collection view cell it's saying that:
has no segue with identifier 'popOutNoteExpanded'.
Not sure how to perform my custom animated transition.
To trigger a segue programmatically, you have to follow steps:
1. Set it up in Storyboard by dragging your desired segue between two view controllers and set its identifier (for example, in your case is "popOutNoteExpanded") in Attributes Inspector section.
2. Call it programmatically
performSegue(withIdentifier: "popOutNoteExpanded", sender: cell)
Please check if you set its identifier correctly or not.
Besides, in your above code, you put an incorrect sender.
In your prepare() method, you use the sender as a UITableViewCell, but you call performSegue() with sender as a IndexPath.
You need a cell by calling:
let cell = tableView.cellForRow(at: indexPath)
And then you can perform a segue:
performSegue(withIdentifier: "popOutNoteExpanded", sender: cell)
Segues are components of storyboard. If you don't have a storyboard, you can't perform segues. But you can use present view controller like this:
let vc = ViewController() //your view controller
self.present(vc, animated: true, completion: nil)
Additional to the correct answer, please be aware that if you are in a navigation stack (say, you are in a Settings page and want to segue to an MyAccountVC) you should use:
let vc = MyAccountVC()
self.navigationController?.pushViewController(vc, animated: true)
If the navigated VC appears with a transparent background during the transition, just set the backgoundColor of it to .white.
In my case I was presenting a TableViewController, without a segue defined, and found it was necessary to instantiate from the storyboard otherwise tableViewCells couldn't be dequeued in cellForRowAt.
let vc = (storyboard.instantiateViewController(withIdentifier: "YourTableViewController") as? YourTableViewController)!
self.navigationController!.pushViewController( vc, animated: true)
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
self.selectedClubState = stateNamesForDisplay[indexPath.row]
self.performSegueWithIdentifier ("Cities", sender: self)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
var clubsToPassToCitiesViewController = [clubObject]()
if segue.identifier == "Cities" {
for club in clubsForTable{
if club.clubState == self.selectedClubState{
clubsToPassToCitiesViewController.append(club)
}
}
let citiesView = segue.destinationViewController as? citiesViewController
citiesView?.clubsForChosenCity = clubsToPassToCitiesViewController
}
}
Segue is being executed twice leading to the next VC. How can I prevent this from happening?
Delete the current segue in storyboard. Then CTRL-drag from the viewController (not the cell) to the next view controller and name it "Cities". Now, when you select a cell, the didSelectRowAtIndexPath() will fire first and will call performSegueWithIdentifier()
However, if all you're looking to do in the didSelectRowAtIndexPath() is get the row that performed the segue, you can maintain your original setup of having the cell segue from the storyboard, remove didSelectRowAtIndexPath() and in prepareForSegue() do:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if let indexPath = self.tableView.indexPathForSelectedRow {
self.selectedClubState = stateNamesForDisplay[indexPath.row]
}
var clubsToPassToCitiesViewController = [clubObject]()
if segue.identifier == "Cities" {
for club in clubsForTable{
if club.clubState == self.selectedClubState{
clubsToPassToCitiesViewController.append(club)
}
}
let citiesView = segue.destinationViewController as? citiesViewController
citiesView?.clubsForChosenCity = clubsToPassToCitiesViewController
}
}
You are the one executing the segue twice — once automatically in the storyboard (because your segue emanates as an Action Segue from the cell prototype), and once in code when you say self.performSegueWithIdentifier. If you don't want the segue executed twice, remove one of those.
Personally, my recommendation is that you delete didSelectRow entirely and move your self.selectedClubState assignment into prepareForSegue.
I'm trying to pass the value to a second view controller
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "headToDetail" {
let indexPath = self.tableView.indexPathForSelectedRow!.row
print("SELECTED INDEX \(indexPath)")
let destVC = segue.destinationViewController as! SecondViewController
print("Segue TEst \(self.toPass)")
destVC.vieSegue = self.toPass
}
I've remove the didSelectRowAtIndexPath and just going to use the Segue but when I tap on a row cell I get:
fatal error: unexpectedly found nil while unwrapping an Optional value
This is a major update to the original code.
the problem is, that you are creating a new ViewController at line
var destination = SecondViewController()
but then the controller simply deallocates because nothing is pointing to it (there is no reference to it and it falls out of scope). You haven't pushed into it, nor you performed any segue.
How to fix it? Basically there are two options.
Storyboard
If you're working with storyboards, you have to create a segue between the first ViewController and SecondViewController. You have to give it an identifier.
Then in didSelectRowAtIndexPath you will write
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
tableView.deselectRowAtIndexPath(indexPath, animated: true)
let row = indexPath.row
print(fruits[row])
self.toPass = fruits[row]
performSegueWithIdentifier("YOUR_SEGUE_IDENTIFIER", sender: nil)
}
then in prepareForSegue you'll set the property to the destination SecondViewController.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "YOUR_SEGUE_IDENTIFIER" {
let destVC = segue.destinationViewController as! SecondViewController
destVC.vieSegue = self.toPass!
}
}
Manual Push
The second option is to push the controller manually within the didSelectRowAtIndexPath method
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
tableView.deselectRowAtIndexPath(indexPath, animated: true)
let row = indexPath.row
print(fruits[row])
let destination = SecondViewController()
destination.vieSegue = fruits[row]
// if you are using navigation controller
navigationController?.pushViewController(destination, animated: true)
// if you want to present it modally
// presentViewController(destination, animated: true, completion: nil)
}
The second version doesn't force you to create segues.
It's empty because you create a new object...
var destination = SecondViewController()
...pass it your data...
destination.vieSegue = self.toPass!
...and then let it go out of scope without showing it, saving it, or doing anything else useful.
I have a button inside a cell (PFQueryTableViewController) that is hidden and I want to unhide it when the user performs a certain segue that I call programatically.
When the user taps the cell it segues to a view controller which displays the contents of the cell full screen... I want the button to unhide in this cell when the segue is called so when the user goes back to the table of cells they can see it on the cell they just tapped.
How can I do this?
Edit after questions:
inside cellRowForIndexPath I have the following for the button
cell.myButton.tag = indexPath.row
cell.myButton.addTarget(self, action: "pressed:", forControlEvents: UIControlEvents.TouchUpInside)
cell.myButton.hidden = true
And the segue itself carries information from the cell (stored in Parse backend) across to FullPostViewController from AllPostsTableViewController. The code for that is this (would I call the unhide in here somewhere?):
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
self.performSegueWithIdentifier("showFullPost", sender: self)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "showFullPost" {
let indexPath = self.tableView.indexPathForSelectedRow
let fullPostVC = segue.destinationViewController as! FullPostViewController
let object = self.objectAtIndexPath(indexPath)
fullPostVC.post = object?.objectForKey("postContent") as? String
let likeCount = object!.objectForKey("likedBy")!.count
fullPostVC.likesCounted = String(likeCount)
self.tableView.deselectRowAtIndexPath(indexPath!, animated: true)
}
}
(Answer thoroughly edited after thorough edit of question)
One possible solution follows below.
Since you mention table cells (each containing a button; I'll assume UIButton), I assume you populate your table view cells with UITableViewCell objects; some fancy subclass to the latter. In this class:
If you haven't already, create an #IBOutlet from your button as a property in this class.
Overload the method setSelected(...) to un-hide your button in case the UITableViewCell is selected (which will precede the segue)
Hence, in your UITableViewCell subclass, you should be able to do something along the lines:
// ...TableViewCell.swift
Import UIKit
// ...
class ...TableViewCell: UITableViewCell {
// Properties
#IBOutlet weak var button: UIButton!
// button contained in UITableViewCell
// ...
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// If table cell is selected (after which segue will follow),
// un-hide button.
if (selected) {
button.hidden = false
}
}
}
Hopefully this will achieve your goal.
I am implementing a commentView for my app. I have a main view which is tableview contains picture and a button to go comment view.
I want that when user tap comment button in table view, view shows comment view and pass PFObject by prepareforSegue method.
now comment button works, but I have an error from prepareforsegue
here is my code.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if (segue.identifier == "mainToComment") {
let destViewController : CommentVC = segue.destinationViewController as! CommentVC
destViewController.parentObjectID = parentObjectID
let selectedRowIndex = self.tableView.indexPathForSelectedRow
destViewController.object = (postsArray[(selectedRowIndex?.row)!] as? PFObject)
and here is my how my button works.
#IBAction func commentButtonTapped(sender: AnyObject) {
let button = sender as! UIButton
let view = button.superview!
let cell = view.superview as! MainTVCE
let indexPath = tableView.indexPathForCell(cell)
parentObjectID = postsArray[(indexPath?.row)!].objectId!!
when I debug, selectedRowIndex has no value(nil)
I think it cause of I tap button instead of cell.
How can I set indexPath for this?
or
How can I make it work?
I don't know name of your main TableViewCell view controller. Assume that, I name this view controller is MainTableViewCell.
I create a closure in MainTableViewCell:
var didRequestToShowComment:((cell:UITableViewCell) -> ())?
When button comment is tapped:
#IBAction func commentButtonTapped(sender: AnyObject) {
self.didRequestToShowComment?(self) // self is this UITableViewCell
}
In table cellForRowAtIndex... of your main view controller.
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
...
mainTableViewCell.didRequestToShowComment = { (cell) in
let indexPath = tableView.indexPathForCell(cell)
let objectToSend = postsArray[indexPath.row] as? PFObject
// Show your Comment view controller here, and set object to send here
}
...
return cell
}