Asyncdisplaykit: Is it possible to self-sizing the Header with UICollectionFlowLayout?

[muukii]

I did not find an API that returns the constrainedSize of the header.

extension ViewController: ASCollectionDelegate, UICollectionViewDelegateFlowLayout {

  func collectionNode(_ collectionNode: ASCollectionNode, constrainedSizeForItemAt indexPath: IndexPath) -> ASSizeRange {
    return ASSizeRange(
      min: CGSize(width: collectionNode.frame.width, height: 0),
      max: CGSize(width: collectionNode.frame.width, height: .infinity)
    )
  }

  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
    // 🔥 I want to return the value so that it becomes the size of CellNode itself here
    return CGSize(width: collectionView.frame.width, height: 40)
  }
}

[haashem]

would you mind to clarify your question? what do you want to achieve ?

[muukii]

@hashemp206
Cell can decide the size based on constrainedSize, but I do not know how to realize it with Header.

[haashem]

the simplest solution is add another section with only one cell that act as the header.

[muukii]

@hashemp206
Thank you very much.
That way is certainly possible.
However, I would like to know if there is a way to realize it with SectionHeader.

[Adlai-Holler]

@muukii Hi! If you set UICollectionViewFlowLayout.headerReferenceSize or implement - (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout referenceSizeForHeaderInSection:(NSInteger)section; then ASDK will treat the reference size as a maximum size and measure the header with constrained size range: {{0, 0}, {cv.width, headerReferenceSize}} (for a vertical flow). Does that make sense?

[muukii]

@Adlai-Holler
Currently it is implemented as follows.

  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
          // TODO: Self-sizing
      return CGSize(width: collectionView.frame.width, height: 60)
    }
  }

The UI looks like this.

Header is self-sizing but ReusableView does not seem to be able to fit the size of Header.

[muukii]

@Adlai-Holler
I am reading the ASDK code.
HeaderReferenceSize is used only as max and UICollectionReusableView is not scaled down according to ASCellNode, right?

[muukii]

👀

[apeidos]

+1
Is it possible to make supplementary views size themselves or not?

EDIT

My apologies. This seems to be an issue in 1.9.x. Supplementary nodes resize fine in at least 2.1

[CodingMeSwiftly]

I've created a sample that has working self-sizing supplementary nodes.
https://github.com/ImJCabus/ASCollectionNodeAutoHeader
So the answer is: Yes, it's certainly possible to employ self-sizing headers.

@hannahmbanana @appleguy
Maybe close this issue?

[maicki]

Hey @muukii it seems @ImJCabus and others in this thread answered your questions. I will close this issue for now. Thanks!

For further questions please join our Slack channel: http://asyncdisplaykit.org/slack.html

[muukii]

Oh Thanks. I'll check it