CODEWITHSUNDEEP
iosibactionuicollectionviewnsindexpathuicollectionviewcell
brush51
brush51

Reputation: 5771

how to access from UICollectionViewCell the indexPath of the Cell in UICollectionView

i want to animate the UICollectionViewCell when action is called.
i have done UICollectionViewCell in Interface Builder, the UICollectionView also. Now i want to get the correct indexPath at my actionBtnAddToCard method.

thats the way i try it now (method in ProduktViewCell.m): 

- (IBAction)actionAddToCart:(id)sender {
    XLog(@"");

    // see this line
    NSIndexPath *indexPath = ??** how can i access the correct indexPath**??;
    SortimentViewController *svc = [[SortimentViewController alloc] initWithNibName:@"SortimentViewController_iPad" bundle:[NSBundle mainBundle]];
    [svc.collectionViewProdukte cellForItemAtIndexPath:indexPath];

    [svc collectionView:svc.collectionViewProdukte didSelectItemAtIndexPath:indexPath];
}

SortimentViewController is the viewController which inherits the UICollectionView.
how to acces the correct indexPath?

UPDATE 1: edited post for better understanding.

Upvotes: 21

Views: 64639

Answers (13)

Eliseo A.
Eliseo A.

Reputation: 39

 internal func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: “cell_id”, for: indexPath)
    
    let bttn_obj = UIButton(frame: CGRect(x: 5.5, y: 5.5, width: 22, height: 22))
    bttn_obj.addTarget(self, action: #selector(bttn_action), for: UIControl.Event.touchUpInside)
    cell.addSubview(bttn_obj)        
    
    return cell
}

@IBAction func bttn_action(_ sender: UIButton) -> Void {
    
    let cell_view = sender.superview as! UICollectionViewCell
    let index_p : IndexPath = self.collectionview.indexPath(for: cell_view)!
    
    print(index_p)
 
}

Upvotes: 0

Alex Kolovatov
Alex Kolovatov

Reputation: 879

Xcode10. Swift 4.2 version.

extension UICollectionView {

  func indexPathForView(view: AnyObject) -> IndexPath? {
      guard let view = view as? UIView else { return nil }
      let senderIndexPath = self.convert(CGPoint.zero, from: view)
      return self.indexPathForItem(at: senderIndexPath)
  }

}

Usage:

// yourView can be button for example
let indexPath = collectionView.indexPathForView(view: yourView)

Upvotes: 1

bpolat
bpolat

Reputation: 3908

Swift 3 Solution : Based on Ishan Handa's Answer

extension UICollectionView {
func indexPathForView(view: AnyObject) -> IndexPath? {
    let originInCollectioView = self.convert(CGPoint.zero, from: (view as! UIView))
    return self.indexPathForItem(at: originInCollectioView) as IndexPath?
  }
}

Usage: 

func deleteCell(sender:UIButton){
    var indexPath:IndexPath? = nil
    indexPath = self.collectionView.indexPathForView(view: sender)        
    print("index path : \(indexPath)")
}

Upvotes: 2

Ishan Handa
Ishan Handa

Reputation: 2281

Swift solution: A UICollectionView extension like this one can be useful for this.

extension UICollectionView {
    func indexPathForView(view: AnyObject) -> NSIndexPath? {
        let originInCollectioView = self.convertPoint(CGPointZero, fromView: (view as! UIView))
        return self.indexPathForItemAtPoint(originInCollectioView)
    }
}

Usage becomes easy everywhere.

let indexPath = collectionView.indexPathForView(button)

Upvotes: 6

Vasu Ashok
Vasu Ashok

Reputation: 1413

Even though many answer i found here .this will be shortest and useful irrespective of the view hierarchy 

- (void) actionAddToCart:(id)sender
{
    id view = [sender superview];

    while (view && [view isKindOfClass:[UICollectionViewCell class]] == NO) 
    {
        view = [view superview];
    }
    NSIndexPath *thisIndexPath = [self.collectionView indexPathForCell:view];

    NSLog(@"%d actionAddToCart pressed",thisIndexPath.row);
}

Upvotes: 1

Echelon
Echelon

Reputation: 7922

Using code like [[button superview] superview] is fragile and not future-proof; indeed, it's not even guaranteed to work on all iOS versions unless you explicitly test it. I always use an iterative helper method for this purpose:-

- (UIView *)superviewWithClassName:(NSString *)className fromView:(UIView *)view
{
    while (view)
    {
        if ([NSStringFromClass([view class]) isEqualToString:className])
        {
            return view;
        }
        view = view.superview;
    }
    return nil;
}

Then I call it from the button handler like so:-

- (IBAction)buttonClicked:(id)sender
{
    UIButton *button = (UIButton *)sender;
    UICollectionViewCell *cell = (UICollectionViewCell *)
                                [self superviewWithClassName:@"UICollectionViewCell"
                                fromView:button];
    if (cell)
    {
        NSIndexPath *indexPath = [self.collectionView indexPathForCell:cell];
        // do whatever action you need with the indexPath...
    }
}

UPDATE: Swift version of superviewWithClassName. Made it a class method since it never references self.

static func superviewWithClassName(className:String, fromView view:UIView?) -> UIView? {
    guard let classType = NSClassFromString(className) else {
        return nil
    }
    var v:UIView? = view
    while (v != nil) {
        if v!.isKindOfClass(classType) {
            return v
        }
        v = v!.superview
    }
    return nil
}

and some code to call it, either from prepareForSegue or a button handler:-

guard let cell = UIView.superviewWithClassName("UICollectionViewCell", fromView: sender as? UIView) as? UITableViewCell else {return}

Upvotes: 6

arsenius
arsenius

Reputation: 13246

You almost certainly have a UICollectionViewCell subclass. Just add a property and set the indexPath in cellForItemAtIndexPath.

Upvotes: 0

Markus
Markus

Reputation: 686

You can do it like this, indexPathsForVisibleItems will return array of NSIndexPaths for items currently visible on view and first object returns the first one (if you have one cell per view). 

NSIndexPath *indexPath = [[svc.collectionViewProdukte indexPathsForVisibleItems] firstObject]

Upvotes: 3

Ego Slayer
Ego Slayer

Reputation: 2067

Do Not Depend on view. Try this.

CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.collectionView];
NSIndexPath *indexPath = [self.collectionView indexPathForItemAtPoint:buttonPosition];

NSLog(@"%ld", (long)indexPath.row);

Upvotes: 7

RFAustin
RFAustin

Reputation: 315

//Note: this is for a storyboard implementation

// here is code for finding the row and section of a textfield being edited in a uicollectionview
UIView *contentView = (UIView *)[textField superview];
UICollectionViewCell *cell = (UICollectionViewCell *)[contentView superview];
cell = (UICollectionViewCell *)[contentView superview];

// determine indexpath for a specific cell in a uicollectionview
NSIndexPath *editPath = [myCollectionView indexPathForCell:cell];
int rowIndex = editPath.row;
int secIndex = editPath.section;

Upvotes: 1

Carmen
Carmen

Reputation: 6263

- (IBAction)actionAddToCart:(id)sender {
   NSIndexPath *indexPath;
   indexPath = [self.collectionView indexPathForItemAtPoint:[self.collectionView convertPoint:sender.center fromView:sender.superview]]; 
   ...
}

Upvotes: 25

Shubhank
Shubhank

Reputation: 21805

if you know the view hierarchy it is easy.

UIButton *button = (UiButton *) sender;

if the button is like this - > UITableViewCell - > button

then you can get cell like this 

UITableViewCell *cell = (UITableViewCell *)[button superview];

if the button is like this - > UITableViewCell - > content view -> button

UITableViewCell *cell = (UITableViewCell *)[[button superview] superview];

and finally index path can be extracted like this 

NSIndexPath *indexPath = [self.table_View indexPathForCell:cell];

Upvotes: 17

Tim
Tim

Reputation: 226

If you want to animate a specific cell, you need to get a reference to that cell. Simply calling 

[svc.collectionViewProdukte cellForItemAtIndexPath:indexPath];

does nothing. You need to keep the cell that the method returns, like this:

UICollectionViewCell *cell = [svc.collectionViewProdukte cellForItemAtIndexPath:indexPath];

After that, go ahead and animate:

[UIView animateWithDuration:0.2f animations:^{
    cell.transform = CGAffineTransformMakeScale(0.5f, 0.5f);
}];

Upvotes: 2

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