# `BCCollectionViewDelegate collectionView:willShowViewController:forItem:`

*Instance Method*

## Declaration

```swift
func collectionView(_ collectionView: BCCollectionView!, willShow viewController: NSViewController!, forItem anItem: Any!)
```

```objc
- (void) collectionView:(BCCollectionView *) collectionView willShowViewController:(NSViewController *) viewController forItem:(id) anItem;
```

```python
collectionView_willShowViewController_forItem_(collectionView: BCCollectionView, viewController: NSViewController, anItem: object)
```