fix: resolve #83 the text editor input content offset reset after input character issue

Mastodon.xcodeproj/project.pbxproj

@@ -220,7 +220,7 @@
 		DB68A05D25E9055900CFDF14 /* Settings.bundle in Resources */ = {isa = PBXBuildFile; fileRef = DB68A05C25E9055900CFDF14 /* Settings.bundle */; };
 		DB68A06325E905E000CFDF14 /* UIApplication.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB68A06225E905E000CFDF14 /* UIApplication.swift */; };
 		DB6B35182601FA3400DC1E11 /* MastodonAttachmentService.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB6B35172601FA3400DC1E11 /* MastodonAttachmentService.swift */; };
-		DB6B351E2601FAEE00DC1E11 /* ComposeStatusAttachmentTableViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB6B351D2601FAEE00DC1E11 /* ComposeStatusAttachmentTableViewCell.swift */; };
+		DB6B351E2601FAEE00DC1E11 /* ComposeStatusAttachmentCollectionViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB6B351D2601FAEE00DC1E11 /* ComposeStatusAttachmentCollectionViewCell.swift */; };
 		DB6C8C0F25F0A6AE00AAA452 /* Mastodon+Entity+Error.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB6C8C0E25F0A6AE00AAA452 /* Mastodon+Entity+Error.swift */; };
 		DB71FD2C25F86A5100512AE1 /* AvatarStackContainerButton.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB71FD2B25F86A5100512AE1 /* AvatarStackContainerButton.swift */; };
 		DB71FD3625F8A16C00512AE1 /* APIService+Persist+PersistMemo.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB71FD3525F8A16C00512AE1 /* APIService+Persist+PersistMemo.swift */; };
@@ -618,7 +618,7 @@
 		DB68A05C25E9055900CFDF14 /* Settings.bundle */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.plug-in"; path = Settings.bundle; sourceTree = "<group>"; };
 		DB68A06225E905E000CFDF14 /* UIApplication.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UIApplication.swift; sourceTree = "<group>"; };
 		DB6B35172601FA3400DC1E11 /* MastodonAttachmentService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MastodonAttachmentService.swift; sourceTree = "<group>"; };
-		DB6B351D2601FAEE00DC1E11 /* ComposeStatusAttachmentTableViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ComposeStatusAttachmentTableViewCell.swift; sourceTree = "<group>"; };
+		DB6B351D2601FAEE00DC1E11 /* ComposeStatusAttachmentCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ComposeStatusAttachmentCollectionViewCell.swift; sourceTree = "<group>"; };
 		DB6C8C0E25F0A6AE00AAA452 /* Mastodon+Entity+Error.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Mastodon+Entity+Error.swift"; sourceTree = "<group>"; };
 		DB71FD2B25F86A5100512AE1 /* AvatarStackContainerButton.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AvatarStackContainerButton.swift; sourceTree = "<group>"; };
 		DB71FD3525F8A16C00512AE1 /* APIService+Persist+PersistMemo.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "APIService+Persist+PersistMemo.swift"; sourceTree = "<group>"; };
@@ -1458,7 +1458,7 @@
 			children = (
 				DB789A2A25F9F7AB0071ACA0 /* ComposeRepliedToStatusContentCollectionViewCell.swift */,
 				DB789A1B25F9F76A0071ACA0 /* ComposeStatusContentCollectionViewCell.swift */,
-				DB6B351D2601FAEE00DC1E11 /* ComposeStatusAttachmentTableViewCell.swift */,
+				DB6B351D2601FAEE00DC1E11 /* ComposeStatusAttachmentCollectionViewCell.swift */,
 				DB87D4442609BE0500D12C0D /* ComposeStatusPollOptionCollectionViewCell.swift */,
 				DB87D4502609CF1E00D12C0D /* ComposeStatusPollOptionAppendEntryCollectionViewCell.swift */,
 				DB2FF50F260B113300ADA9FE /* ComposeStatusPollExpiresOptionCollectionViewCell.swift */,
@@ -2296,7 +2296,7 @@
 				0FAA101C25E10E760017CCDE /* UIFont.swift in Sources */,
 				2D38F1D525CD465300561493 /* HomeTimelineViewController.swift in Sources */,
 				DB98338825C945ED00AD9700 /* Assets.swift in Sources */,
-				DB6B351E2601FAEE00DC1E11 /* ComposeStatusAttachmentTableViewCell.swift in Sources */,
+				DB6B351E2601FAEE00DC1E11 /* ComposeStatusAttachmentCollectionViewCell.swift in Sources */,
 				2DA7D04425CA52B200804E11 /* TimelineLoaderTableViewCell.swift in Sources */,
 				DB87D44B2609C11900D12C0D /* PollOptionView.swift in Sources */,
 				DBE3CDFB261C6CA500430CC6 /* FavoriteViewModel.swift in Sources */,

Mastodon/Diffiable/Section/ComposeStatusSection.swift

@@ -92,7 +92,12 @@ extension ComposeStatusSection {
                     .receive(on: DispatchQueue.main)
                     .sink { text in
                         // self size input cell
+                        // needs restore content offset to resolve issue #83
+                        let oldContentOffset = collectionView.contentOffset
                         collectionView.collectionViewLayout.invalidateLayout()
+                        collectionView.layoutIfNeeded()
+                        collectionView.contentOffset = oldContentOffset
+                        
                         // bind input data
                         attribute.composeContent.value = text
                     }
@@ -187,6 +192,7 @@ extension ComposeStatusSection {
             case .pollOption(let attribute):
                 let cell = collectionView.dequeueReusableCell(withReuseIdentifier: String(describing: ComposeStatusPollOptionCollectionViewCell.self), for: indexPath) as! ComposeStatusPollOptionCollectionViewCell
                 cell.pollOptionView.optionTextField.text = attribute.option.value
+                cell.pollOptionView.optionTextField.placeholder = L10n.Scene.Compose.Poll.optionNumber(indexPath.item + 1)
                 cell.pollOption
                     .receive(on: DispatchQueue.main)
                     .assign(to: \.value, on: attribute.option)

Mastodon/Scene/Compose/CollectionViewCell/ComposeStatusAttachmentCollectionViewCell.swift

@@ -1,5 +1,5 @@
 //
-//  ComposeStatusAttachmentTableViewCell.swift
+//  ComposeStatusAttachmentCollectionViewCell.swift
 //  Mastodon
 //
 //  Created by MainasuK Cirno on 2021-3-17.

Mastodon/Scene/Compose/ComposeViewController.swift

@@ -68,18 +68,7 @@ final class ComposeViewController: UIViewController, NeedsDependency {
     
     let composeToolbarView = ComposeToolbarView()
     var composeToolbarViewBottomLayoutConstraint: NSLayoutConstraint!
-    let composeToolbarBackgroundView: UIView = {
+    let composeToolbarBackgroundView = UIView()
-        let backgroundView = UIView()
-        // set keyboard background to make the keyboard blurred color fixed
-        backgroundView.backgroundColor = UIColor(dynamicProvider: { traitCollection -> UIColor in
-            // avoid elevated color
-            switch traitCollection.userInterfaceStyle {
-            case .light:        return .white
-            default:            return .black
-            }
-        })
-        return backgroundView
-    }()
     
     private(set) lazy var imagePicker: PHPickerViewController = {
         var configuration = PHPickerConfiguration()
@@ -203,13 +192,26 @@ extension ComposeViewController {
         .sink(receiveValue: { [weak self] isShow, state, endFrame, isCustomEmojiComposing in
             guard let self = self else { return }
                         
+            let extraMargin: CGFloat = {
+                if self.view.safeAreaInsets.bottom == .zero {
+                    // needs extra margin for zero inset device to workaround UIKit issue
+                    return self.composeToolbarView.frame.height
+                } else {
+                    // default some magic 16 extra margin
+                    return 16
+                }
+            }()
+            
+            // update keyboard background color
+
             guard isShow, state == .dock else {
-                self.collectionView.contentInset.bottom = self.view.safeAreaInsets.bottom
+                self.collectionView.contentInset.bottom = self.view.safeAreaInsets.bottom + extraMargin
-                self.collectionView.verticalScrollIndicatorInsets.bottom = self.view.safeAreaInsets.bottom
+                self.collectionView.verticalScrollIndicatorInsets.bottom = self.view.safeAreaInsets.bottom + extraMargin
                 UIView.animate(withDuration: 0.3) {
                     self.composeToolbarViewBottomLayoutConstraint.constant = self.view.safeAreaInsets.bottom
                     self.view.layoutIfNeeded()
                 }
+                self.updateKeyboardBackground(isKeyboardDisplay: isShow)
                 return
             }
             // isShow AND dock state
@@ -218,22 +220,23 @@ extension ComposeViewController {
             let contentFrame = self.view.convert(self.collectionView.frame, to: nil)
             let padding = contentFrame.maxY - endFrame.minY
             guard padding > 0 else {
-                self.collectionView.contentInset.bottom = self.view.safeAreaInsets.bottom
+                self.collectionView.contentInset.bottom = self.view.safeAreaInsets.bottom + extraMargin
-                self.collectionView.verticalScrollIndicatorInsets.bottom = self.view.safeAreaInsets.bottom
+                self.collectionView.verticalScrollIndicatorInsets.bottom = self.view.safeAreaInsets.bottom + extraMargin
                 UIView.animate(withDuration: 0.3) {
                     self.composeToolbarViewBottomLayoutConstraint.constant = self.view.safeAreaInsets.bottom
                     self.view.layoutIfNeeded()
                 }
+                self.updateKeyboardBackground(isKeyboardDisplay: false)
                 return
             }
 
-            // add 16pt margin
+            self.collectionView.contentInset.bottom = padding + extraMargin
-            self.collectionView.contentInset.bottom = padding + 16
+            self.collectionView.verticalScrollIndicatorInsets.bottom = padding + extraMargin
-            self.collectionView.verticalScrollIndicatorInsets.bottom = padding + 16
             UIView.animate(withDuration: 0.3) {
                 self.composeToolbarViewBottomLayoutConstraint.constant = padding
                 self.view.layoutIfNeeded()
             }
+            self.updateKeyboardBackground(isKeyboardDisplay: isShow)
         })
         .store(in: &disposeBag)
 
@@ -474,6 +477,20 @@ extension ComposeViewController {
         return imagePicker
     }
     
+    private func updateKeyboardBackground(isKeyboardDisplay: Bool) {
+        guard isKeyboardDisplay else {
+            composeToolbarBackgroundView.backgroundColor = Asset.Scene.Compose.toolbarBackground.color
+            return
+        }
+        composeToolbarBackgroundView.backgroundColor = UIColor(dynamicProvider: { traitCollection -> UIColor in
+            // avoid elevated color
+            switch traitCollection.userInterfaceStyle {
+            case .light:        return .white
+            default:            return .black
+            }
+        })
+    }
+
 }
 
 extension ComposeViewController {