# `BCCollectionViewLayoutOperation.layoutCallback`

*Instance Property*

## Declaration

```swift
var layoutCallback: BCCollectionViewLayoutOperationIterator! { get set }
```

```objc
@property (copy) BCCollectionViewLayoutOperationIterator layoutCallback;
```

```python
layoutCallback() -> BCCollectionViewLayoutOperationIterator
setLayoutCallback_(layoutCallback: BCCollectionViewLayoutOperationIterator)
```