Pill View rendering, performance improvement part 2 (#1894)

* improvdement

* code improvement

ElementX/Sources/Other/Pills/MessageText.swift

@@ -26,7 +26,7 @@ final class MessageTextView: UITextView, PillAttachmentViewProviderDelegate {
         gestureRecognizer as? UILongPressGestureRecognizer == nil
     }
     
-    func invalidateTextAttachmentsDisplay(update: Bool) {
+    func invalidateTextAttachmentsDisplay() {
         attributedText.enumerateAttribute(.attachment,
                                           in: NSRange(location: 0, length: attributedText.length),
                                           options: []) { value, range, _ in
@@ -34,9 +34,7 @@ final class MessageTextView: UITextView, PillAttachmentViewProviderDelegate {
                 return
             }
             self.layoutManager.invalidateDisplay(forCharacterRange: range)
-            if update {
-                updateClosure?()
-            }
+            updateClosure?()
         }
     }
 

ElementX/Sources/Other/Pills/PillAttachmentViewProvider.swift

@@ -24,7 +24,7 @@ protocol PillAttachmentViewProviderDelegate: AnyObject {
     var roomContext: RoomScreenViewModel.Context? { get }
     
     func registerPillView(_ pillView: UIView)
-    func invalidateTextAttachmentsDisplay(update: Bool)
+    func invalidateTextAttachmentsDisplay()
 }
 
 final class PillAttachmentViewProvider: NSTextAttachmentViewProvider {
@@ -44,7 +44,8 @@ final class PillAttachmentViewProvider: NSTextAttachmentViewProvider {
     override func loadView() {
         super.loadView()
 
-        guard let textAttachmentData = (textAttachment as? PillTextAttachment)?.pillData else {
+        guard let textAttachment = textAttachment as? PillTextAttachment,
+              let pillData = textAttachment.pillData else {
             MXLog.failure("[PillAttachmentViewProvider]: attachment is missing data or not of expected class")
             return
         }
@@ -56,15 +57,16 @@ final class PillAttachmentViewProvider: NSTextAttachmentViewProvider {
             context = PillContext.mock(type: .loadUser(isOwn: false))
             imageProvider = MockMediaProvider()
         } else if let roomContext = delegate?.roomContext {
-            context = PillContext(roomContext: roomContext, data: textAttachmentData)
+            context = PillContext(roomContext: roomContext, data: pillData)
             imageProvider = roomContext.imageProvider
         } else {
             MXLog.failure("[PillAttachmentViewProvider]: missing room context")
             return
         }
         
-        let view = PillView(imageProvider: imageProvider, context: context) { [weak self] in
-            self?.delegate?.invalidateTextAttachmentsDisplay(update: true)
+        let view = PillView(imageProvider: imageProvider, context: context) { [weak self, weak textAttachment] in
+            textAttachment?.invalidateLastBounds()
+            self?.delegate?.invalidateTextAttachmentsDisplay()
         }
         let controller = UIHostingController(rootView: view)
         controller.view.backgroundColor = .clear
@@ -93,5 +95,5 @@ extension WysiwygTextView: PillAttachmentViewProviderDelegate {
         (mentionDisplayHelper as? ComposerMentionDisplayHelper)?.roomContext
     }
     
-    func invalidateTextAttachmentsDisplay(update: Bool) { }
+    func invalidateTextAttachmentsDisplay() { }
 }

ElementX/Sources/Other/Pills/PillTextAttachment.swift

@@ -26,13 +26,22 @@ final class PillTextAttachment: NSTextAttachment {
     }
     
     private(set) var pillData: PillTextAttachmentData!
+    private var lastBounds: CGRect?
+    
+    func invalidateLastBounds() {
+        lastBounds = nil
+    }
     
     override func attachmentBounds(for textContainer: NSTextContainer?, proposedLineFragment lineFrag: CGRect, glyphPosition position: CGPoint, characterIndex charIndex: Int) -> CGRect {
+        if let lastBounds {
+            return lastBounds
+        }
         var rect = super.attachmentBounds(for: textContainer, proposedLineFragment: lineFrag, glyphPosition: position, characterIndex: charIndex)
         
         let fontData = pillData.fontData
         // Align the pill text vertically with the surrounding text.
         rect.origin.y = fontData.descender + (fontData.lineHeight - rect.height) / 2.0
+        lastBounds = rect
         return rect
     }
 }