I have a collectionView used for scrolling between pages, inside of one of these full page cells I have another collectionView with cells. How do I perform a segue when one of the cells inside of the inner most collectionView is tapped.
You will need a delegate on the cells with collection view, that will need to be notified when a particular cell is selected:
protocol CollectionCellDelegate: class {
func selectedItem()
}
class CollectionCell: UITableViewCell {
weak var delegate: CollectionCellDelegate?
// ...
func collectionView(_ collectionView: UICollectionView,
didSelectItemAt indexPath: IndexPath) {
self.delegate?.selectedItem()
}
}
And in the TableViewController you will have to implement that delegate to perform segue from it (you have to perform segue from UIViewController subclass, but the UITableViewCell is not subclassing it, that's why you need the delegate pattern).
class TableViewController: UITableViewController, CollectionCellDelegate {
// ...
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "CollectionCell", for: indexPath) as! CollectionCell
// set its delegate to self
cell.delegate = self
return cell
}
func selectedItem() {
// here you can perform segue
performSegue(withIdentifier: "mySegue", sender: self)
}
}
I haven't passed any argument to the delegate, but you can of course use arguments to pass any information that you need for the segue (e.g., the id of the collection cell that was selected, etc.).
When you tap on an item in collectionView, the following delegate method will be called (if you wired up everything properly) func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath)... notice that the first param is collectionView itself.
Depending on how you set it up...
if you have two collectionViews within one UIViewController then you can do..
func collectionView(_ collectionView: UICollectionView,
didSelectItemAt indexPath: IndexPath) {
if collectionView == self.innerCollectionView {
// performSegue...
}
}
if you have two view controllers, one for outer and another for inner.. then you can create use delegate pattern to let the outer know which item got selected, and segue using that info.
Related
I have a UICollectionView that appropriately recognizes taps on its cells in its collectionView(didSelectItemAt: ) delegate method.
However, I then embedded a collection view within the cell itself (so that each cell has its own collection view inside of it), but now the parent cell is not recognizing any taps anymore, I'm assuming because the embedded collection view is eating them up.
Is there some property that needs to be set so that the original (parent) cells register taps again even with their embedded collection views?
This functionality can be confusing, as users are accustomed to "something else" happening when interacting with a control in a table view cell, rather than it selecting (or also selecting) the row itself.
However, if you really want to do that...
One approach is to use a closure in your cell. When you handle didSelectItemAt use the closure to tell the table view controller to select the row.
Note that Apple's docs point out:
Note
Selecting a row programmatically doesn't call the delegate methods tableView(_:willSelectRowAt:) or tableView(_:didSelectRowAt:), nor does it send selectionDidChangeNotification notifications to observers.
So, if you need to execute code when a table view row is selected, you'll need to call that yourself - something like this:
func myTableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print("My didSelectRowAt:", indexPath)
}
Using the code in my answer to your previous question...
In SomeTableCell add this closure setup:
public var didSelectClosure: ((UITableViewCell) ->())?
and, still in SomeTableCell:
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print("collectionView didSelecteItemAt:", indexPath)
print("Calling closure...")
didSelectClosure?(self)
}
Next, in cellForRowAt in the table view controller, set the closure:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "someTableCell", for: indexPath) as! SomeTableCell
cell.rowTitleLabel.text = "Row \(indexPath.row)"
cell.thisData = myData[indexPath.row]
cell.didSelectClosure = { [weak self] c in
guard let self = self,
let idx = tableView.indexPath(for: c)
else { return }
// select the row
tableView.selectRow(at: idx, animated: true, scrollPosition: .none)
// that does not call didSelectRowAt, so call our own func
// if we want something to happen on row selection
self.myTableView(tableView, didSelectRowAt: idx)
}
return cell
}
you can implement UICollectionViewDataSource & UICollectionViewDelegate methods of inner collectionViews inside the cells itself & pass the events with closure to main class with main UICollectionView.
I just started learning swift and don't understand how present ViewController from custom UITableViewCell when I clicked to my Collection Cell.
I have custom class MainTableViewCell.swift that has CollectionView
extension MainTableViewCell: UICollectionViewDelegate, UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return videos.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "MainCollectionViewCell", for: indexPath) as! MainCollectionViewCell
let video = videos[indexPath.item]
cell.titleLabel.text = video.title
cell.dateLabel.text = video.date
cell.bgImageView.load(urlString: "https://i.ytimg.com/vi/\(video.image!)/hqdefault.jpg")
cell.layer.masksToBounds = true
cell.layer.cornerRadius = 15.0
return cell
}
What can I do in method didSelectItemAt?
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
}
You just need to set a delegation pattern in order to present a new view controller from a class that contains your table view. The steps are:
Create a TableViewCellDelegate protocol, and inside a table view cell class inside didSelectItemAt method call the protocol's method (also pass the information of collection view cell in method parameters which is required).
Make your table view containing view controller conform to this protocol.
Inside the method where you conform the TableViewDelegate present a new view controller.
p.s don't forget to set the delegate property to self in cellForRowAt method of table view.
I have a UICollectionViewController, which scrolls vertically(like a tableview). I created a custom UICollectionViewCell. Inside of a custom cell, there are checkmarks. I need some kind of event to click when the user clicks on a checkmark.
What I tried, was overriding:
override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print("clicked")
}
but that only executes when the use clicks on a cell. But, asI stated above, the cell contains checkmarks...I need to find out when each individual check mark is clicked.
Is this possible?
You can add an IBAction to the UICollectionViewCell class and handle the tap from that IBAction, if you need it to change something on the Parent view controller you have a couple of options, you can use a delegate or pass the controller to the cell.
On the parent view controller :
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCellWithReuseIdentifier("Cell", forIndexPath: indexPath) as! CustomCollectionViewCell
cell.controller = self
return cell
}
On the UICollectionViewCell class:
var controller: ParentViewController?
#IBAction func checkmarkPressed(sender: UIButton) {
print("checkmarkPressed")
controller.someFunction()
}
I want to set a variable to different string when a certain CollectionView cell is tapped. So cell1 is tapped then var cellTapped = "cell1", cell 2 is tapped then var cellTapped = "cell2" and so on. It was suggested that I
"create a custom cell and hold the value as property and read this
value on didSelectCell()"
but I'm not sure how to do this (newbie).
(Swift 3)
You need to set UICollectionViewDelegate to your ViewController and then implement didSelectItemAt IndexPath that gets called when a cell is tapped.
Something like this:
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
cellTapped = "cell" + String(indexPath.row)
}
You could also have an array of Strings and index into the array based on the indexPath.row:
let cellStringValues = ["cell1", "cell2", "cell3", ... , "celln"]
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
cellTapped = cellStringValues[indexPath.row]
}
Setup your view controller to be the delegate of the UICollectionView. Your view controller should inherit from UICollectionViewDelegate. Then in the viewDidLoad() for the VC set the delegate variable for the UICollectionView to be the ViewController. To catch selection events override the following UICollectionViewDelegate function.
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
cellTapped = "cell\(indexPath.row)"
}
Check out https://www.raywenderlich.com/136159/uicollectionview-tutorial-getting-started for more details on working with collection views
hello I have implemented a UICollectionView in my controller. There are lots of info I am displaying on each cell. When user clicks the particular cell I want to pass all the info that was in the cell to another controller.
As I am displaying all the data from db in the cells and cells are generating dynamically so I think one way could be to pass just a record id from one cell to this function didSelectItemAtIndexPath and then in the second controller I query again from the database. But I think that would not be the good idea. and also I don't know how can I pass the id or any info here in this function didSelectItemAtIndexPath.
So in short I want to display all the info in another controller that is being displayed in that cell which is being clicked
here is my code
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath
indexPath: NSIndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCellWithReuseIdentifier("Cell",
forIndexPath: indexPath) as! CardsCollectionCell
cell.usernameLabel.text = (((dict["\(indexPath.item)"] as?NSDictionary)!["Trip"] as?NSDictionary)!["userName"] as?NSString)! as String
cell.feeLabel.text = (((dict["\(indexPath.item)"] as?NSDictionary)!["Trip"] as?NSDictionary)!["fee"] as?NSString)! as String
return cell
}
func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
}
So let's going to explain by parts, the didSelectItemAtIndexPath delegate method is used to know what UICollectionViewCell was tapped in the UICollectionViewController, you can get the UICollectionViewCell very easily using the method cellForItemAtIndexPath(it's not the same as collectionView(collectionView: UICollectionView, cellForItemAtIndexPath) like in the following code:
func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
let cell = self.collectionView?.cellForItemAtIndexPath(indexPath) as! CardsCollectionCell
// access to any property inside the cell you have.
// cell.usernameLabel.text
}
So regarding in short I want to display all the info in another controller that is being displayed in that cell which is being clicked
You can use the didSelectItemAtIndexPath method without any problem to launch a manual segue using the method performSegueWithIdentifier to another UIViewController and just in the prepareForSegue pass any data you need to pass to the another UIViewController. See the following code:
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
// the identifier of the segue is the same you set in the Attributes Inspector
self.performSegueWithIdentifier("segueName", sender: self)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if(segue.identifier == "segueName") {
// this is the way of get the indexPath for the selected cell
let indexPath = self.collectionView.indexPathForSelectedRow()
let row = indexPath.row
// get a reference to the next UIViewController
let nextVC = segue.destinationViewController as! NameOfYourViewController
}
}
I hope this help you.