Merge pull request #321 from kyleve/kve/fix-supplementary-reuse-bug

Fix supplementary reuse bug by ensuring we track the right view instance in our displayed views cache
square · Aug 31, 2021 · 0e55435 · 0e55435
2 parents 600ca93 + b3e27d3
commit 0e55435
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Showing 5 changed files with 12 additions and 8 deletions.
diff --git a/ListableUI/Sources/Internal/PresentationState/PresentationState.SectionState.swift b/ListableUI/Sources/Internal/PresentationState/PresentationState.SectionState.swift
@@ -14,8 +14,8 @@ extension PresentationState
     {
         var model : Section
 
-        var header : HeaderFooterViewStatePair
-        var footer : HeaderFooterViewStatePair
+        let header : HeaderFooterViewStatePair
+        let footer : HeaderFooterViewStatePair
 
         var items : [AnyPresentationItemState]
 

diff --git a/ListableUI/Sources/Internal/PresentationState/PresentationState.swift b/ListableUI/Sources/Internal/PresentationState/PresentationState.swift
@@ -16,10 +16,10 @@ final class PresentationState
 
     var refreshControl : RefreshControlState?
 
-    var containerHeader : HeaderFooterViewStatePair
-    var header : HeaderFooterViewStatePair
-    var footer : HeaderFooterViewStatePair
-    var overscrollFooter : HeaderFooterViewStatePair
+    let containerHeader : HeaderFooterViewStatePair
+    let header : HeaderFooterViewStatePair
+    let footer : HeaderFooterViewStatePair
+    let overscrollFooter : HeaderFooterViewStatePair
 
     var sections : [PresentationState.SectionState]
 

diff --git a/ListableUI/Sources/Internal/SupplementaryContainerView.swift b/ListableUI/Sources/Internal/SupplementaryContainerView.swift
@@ -64,6 +64,8 @@ final class SupplementaryContainerView : UICollectionReusableView
         ) as! SupplementaryContainerView
 
         view.reuseCache = reuseCache
+
+        // TODO: We need to also set this during on-screen updates; I don't think it's updated correctly now.
         view.environment = environment
 
         return view

diff --git a/ListableUI/Sources/ListView/ListView.Delegate.swift b/ListableUI/Sources/ListView/ListView.Delegate.swift
@@ -163,7 +163,7 @@ extension ListView
 
             headerFooter.willDisplay(view: container)
 
-            self.displayedSupplementaryItems[ObjectIdentifier(view)] = headerFooter
+            self.displayedSupplementaryItems[ObjectIdentifier(container)] = headerFooter
         }
 
         func collectionView(

diff --git a/ListableUI/Tests/Internal/SupplementaryContainerViewTests.swift b/ListableUI/Tests/Internal/SupplementaryContainerViewTests.swift
@@ -89,7 +89,9 @@ class SupplementaryContainerViewTests: XCTestCase
 
         // Add a header
 
-        view.headerFooter = self.newHeaderFooter()
+        let header = self.newHeaderFooter()
+
+        view.headerFooter = header
         view.sizeToFit()
 
         // Make sure the view is set