Fallback to non-skeleton Header (#416)

Sometimes my collectionview's header doesn't need to be 'skeletoned' while the content does.  

When  collectionSkeletonView(_ skeletonView: UICollectionView, supplementaryViewIdentifierOfKind: String, at indexPath: IndexPath) -> ReusableCellIdentifier? returns nil, it's best if we fallback to the non-skeleton header.

.github/workflows/CD.yml

@@ -0,0 +1,64 @@
+name: CD
+
+on:
+  pull_request:
+    branches: [main]
+    types: [closed]
+        
+jobs:
+  release_version:
+    if: github.event.pull_request.milestone == null && github.event.pull_request.merged == true
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+          
+      - name: Setup fastlane
+        run: brew install fastlane
+            
+      - name: Publish release
+        id: publish_release
+        uses: release-drafter/release-drafter@v5
+        with: 
+          publish: true
+        env:
+           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Update podspec 
+        run: fastlane bump_version next_version:${{ steps.publish_release.outputs.tag_name }}
+
+      - name: Commit changes
+        uses: stefanzweifel/git-auto-commit-action@v4
+        with:
+          branch: 'main'
+          commit_message: 'Bump version ${{ steps.publish_release.outputs.tag_name }}'
+        env:
+         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}      
+
+      - name: Deploy to Cocoapods
+        env:
+          COCOAPODS_TRUNK_TOKEN: ${{ secrets.COCOAPODS_TRUNK_TOKEN }}
+        run: |
+          set -eo pipefail
+          pod lib lint --allow-warnings
+          pod trunk push --allow-warnings    
+
+      - name: Communicate on PR released
+        uses: unsplash/comment-on-pr@master
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          msg: |
+            Congratulations! 🎉 This was released as part of [SkeletonView ${{ steps.publish_release.outputs.tag_name }}](${{ steps.publish_release.outputs.html_url }}) 🚀  
+
+      - name: Tweet the release
+        uses: ethomson/send-tweet-action@v1
+        with:
+          consumer-key: ${{ secrets.TWITTER_CONSUMER_API_KEY }}
+          consumer-secret: ${{ secrets.TWITTER_CONSUMER_API_SECRET }}
+          access-token: ${{ secrets.TWITTER_ACCESS_TOKEN }}
+          access-token-secret: ${{ secrets.TWITTER_ACCESS_TOKEN_SECRET }}
+          status: |
+            🎉 New release ${{ steps.publish_release.outputs.tag_name }} is out 🚀
+
+            Check out all the changes here: 
+            ${{ steps.publish_release.outputs.html_url }} 

README.md

@@ -4,10 +4,12 @@
     <a href="https://github.com/Juanpe/SkeletonView/actions?query=workflow%3ACI">
       <img src="https://github.com/Juanpe/SkeletonView/workflows/CI/badge.svg">
     </a>
-    <a href="https://codebeat.co/projects/github-com-juanpe-skeletonview-master"><img alt="codebeat badge" src="https://codebeat.co/badges/f854fdfd-31e5-4689-ba04-075d83653e60" /></a>
-    <img src="http://img.shields.io/badge/dependency%20manager-swiftpm%2Bcocoapods%2Bcarthage-green" />
-    <img src="https://img.shields.io/badge/platforms-ios%2Btvos-green" />
-    <a href="https://badge.bow-swift.io/recipe?name=SkeletonView&description=An%20elegant%20way%20to%20show%20users%20that%20something%20is%20happening%20and%20also%20prepare%20them%20to%20which%20contents%20he%20is%20waiting&url=https://github.com/juanpe/skeletonview&owner=Juanpe&avatar=https://avatars0.githubusercontent.com/u/1409041?v=4&tag=1.8.7"><img src="https://raw.githubusercontent.com/bow-swift/bow-art/master/badges/nef-playgrounds-badge.svg" alt="SkeletonView Playground" style="height:20px"></a>   
+    <a href="https://codebeat.co/projects/github-com-juanpe-skeletonview-main"><img alt="codebeat badge" src="https://codebeat.co/badges/1f37bbab-a1c8-4a4a-94d7-f21740d461e9" /></a>
+    <a href="https://cocoapods.org/pods/SkeletonView"><img src="https://img.shields.io/cocoapods/v/SkeletonView.svg?style=flat"></a>
+    <a href="https://github.com/Carthage/Carthage/"><img src="https://img.shields.io/badge/Carthage-compatible-4BC51D.svg?style=flat"></a>
+    <a href="https://swift.org/package-manager/"><img src="https://img.shields.io/badge/SPM-supported-Green.svg?style=flat"></a>
+    <img src="https://img.shields.io/badge/platforms-iOS_tvOS-green" />
+    <a href="https://badge.bow-swift.io/recipe?name=SkeletonView&description=An%20elegant%20way%20to%20show%20users%20that%20something%20is%20happening%20and%20also%20prepare%20them%20to%20which%20contents%20he%20is%20waiting&url=https://github.com/juanpe/skeletonview&owner=Juanpe&avatar=https://avatars0.githubusercontent.com/u/1409041?v=4&tag=1.20.0"><img src="https://raw.githubusercontent.com/bow-swift/bow-art/master/badges/nef-playgrounds-badge.svg" alt="SkeletonView Playground" style="height:20px"></a>   
 </p>
 
 <p align="center">
@@ -43,6 +45,7 @@ Enjoy it! 🙂
 - [✨ Miscellaneous](#-miscellaneous)
 - [❤️ Contributing](#️-contributing)
 - [📢 Mentions](#-mentions)
+- [🏆 Sponsors](#-sponsors)
 - [👨🏻‍💻 Author](#-author)
 - [👮🏻 License](#-license)
 
@@ -563,11 +566,11 @@ Then, when the skeleton appears, you can see the view hierarchy in the Xcode con
 
 * iOS 9.0+
 * tvOS 9.0+
-* Swift 5
-
+* Swift 5.3
 
 ## ❤️ Contributing
 This is an open source project, so feel free to contribute. How?
+
 - Open an [issue](https://github.com/Juanpe/SkeletonView/issues/new).
 - Send feedback via [email](mailto://juanpecatalan.com).
 - Propose your own fixes, suggestions and open a pull request with the changes.
@@ -593,7 +596,12 @@ For more information, please read the [contributing guidelines](https://github.c
 - [Swift News #36](https://www.youtube.com/watch?v=mAGpsQiy6so)
 - [Best iOS articles, new tools & more](https://medium.com/flawless-app-stories/best-ios-articles-new-tools-more-fcbe673e10d)
 
+## 🏆 Sponsors
 
+Open-source projects cannot live long without your help. If you find **SkeletonView** is useful, please consider supporting this 
+project by becoming a sponsor. 
+
+Become a sponsor through [GitHub Sponsors](https://github.com/sponsors/Juanpe) :heart:
 
 ## 👨🏻‍💻 Author
 

SkeletonView.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "SkeletonView"
-  s.version      = "1.18.0"
+  s.version      = "1.20.0"
   s.summary      = "An elegant way to show users that something is happening and also prepare them to which contents he is waiting"
   s.description  = <<-DESC
   Today almost all apps have async processes, as API requests, long runing processes, etc. And while the processes are working, usually developers place a loading view to show users that something is going on.

Sources/Collections/SkeletonCollectionDataSource.swift

@@ -107,7 +107,7 @@ extension SkeletonCollectionDataSource: UICollectionViewDataSource {
             return view
         }
         
-        return UICollectionReusableView()
+        return originalCollectionViewDataSource?.collectionView?(collectionView, viewForSupplementaryElementOfKind: kind, at: indexPath) ?? UICollectionReusableView()
     }
     
 }

Sources/Extensions/UIView+Extension.swift

@@ -14,6 +14,7 @@ enum ViewAssociatedKeys {
     static var labelViewState = "labelViewState"
     static var imageViewState = "imageViewState"
     static var buttonViewState = "buttonViewState"
+    static var headerFooterViewState = "headerFooterViewState"
     static var currentSkeletonConfig = "currentSkeletonConfig"
     static var skeletonCornerRadius = "skeletonCornerRadius"
     static var disabledWhenSkeletonIsActive = "disabledWhenSkeletonIsActive"

Sources/Helpers/PrepareForSkeletonProtocol.swift

@@ -121,3 +121,13 @@ extension UIButton {
         }
     }
 }
+
+extension UITableViewHeaderFooterView {
+    override func prepareViewForSkeleton() {
+        backgroundView?.backgroundColor = .clear
+        
+        if isUserInteractionDisabledWhenSkeletonIsActive {
+            isUserInteractionEnabled = false
+        }
+    }
+}

Sources/Recoverable/Recoverable.swift

@@ -161,3 +161,22 @@ extension UIButton {
         }
     }
 }
+
+extension UITableViewHeaderFooterView {
+    var headerFooterState: RecoverableTableViewHeaderFooterViewState? {
+        get { return ao_get(pkey: &ViewAssociatedKeys.headerFooterViewState) as? RecoverableTableViewHeaderFooterViewState }
+        set { ao_setOptional(newValue, pkey: &ViewAssociatedKeys.headerFooterViewState) }
+    }
+    
+    override func saveViewState() {
+        super.saveViewState()
+        headerFooterState = RecoverableTableViewHeaderFooterViewState(view: self)
+    }
+    
+    override func recoverViewState(forced: Bool) {
+        super.recoverViewState(forced: forced)
+        startTransition { [weak self] in
+            self?.backgroundView?.backgroundColor = self?.headerFooterState?.backgroundViewColor
+        }
+    }
+}

Sources/Recoverable/RecoverableViewState.swift

@@ -59,3 +59,11 @@ struct RecoverableButtonViewState {
         self.title = view.titleLabel?.text
     }
 }
+
+struct RecoverableTableViewHeaderFooterViewState {
+    var backgroundViewColor: UIColor?
+    
+    init(view: UITableViewHeaderFooterView) {
+        self.backgroundViewColor = view.backgroundView?.backgroundColor
+    }
+}