iOS - Scroll up to the beginning loads the end of the conversation

[rinej]

Explanation of Change

Fixed Issues

$ #54870
PROPOSAL: #54870 (comment)

Background
The maintainVisibleContentPosition option is designed to keep the scroll position stable when a user receives a new message. It is used when the scroll is at a fixed offset from the bottom.

Problem
On iOS, when scrolling up, when the property is enabled it causes the view to unexpectedly snap back to the bottom.

Solution
We can apply the maintainVisibleContentPosition prop conditionally - only setting it when the user is not actively scrolling.
This approach allows us to have the benefits of maintainVisibleContentPosition while fixing the snapping issue when scrolling up.

Before:

BrokenScrolling.mp4

After:

FixedScrolling.mp4

Tests

Offline tests

QA Steps

• Log in with a HIGH traffic account
• Open a long conversation (with many actions) and with LONG messages
• Constantly keep scrolling up
• See that old messages are loaded and there is no scrolling to the bottom

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I added steps for the expected offline behavior in the Offline steps section
  • I added steps for Staging and/or Production testing in the QA steps section
  • I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • Android: Native
  • Android: mWeb Chrome
  • iOS: Native
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
  • MacOS: Desktop
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
• I followed proper code patterns (see Reviewing the code)
  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick)
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text shown in the product is localized by adding it to src/languages/* files and using the translation method
    • If any non-english text was added/modified, I used JaimeGPT to get English > Spanish translation. I then posted it in #expensify-open-source and it was approved by an internal Expensify engineer. Link to Slack message:
  • I verified all numbers, amounts, dates and phone numbers shown in the product are using the localization methods
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I followed the guidelines as stated in the Review Guidelines
• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.ts or at the top of the file that uses the constant) are defined as such
• I verified that if a function's arguments changed that all usages have also been updated correctly
• If any new file was added I verified that:
  • The file has a description of what it does and/or why is needed at the top of the file if the code is not self explanatory
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG))
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• If a new page is added, I verified it's using the ScrollView component to make it scrollable when more elements are added to the page.
• I added unit tests for any new feature or bug fix in this PR to help automatically prevent regressions in this user flow.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.

Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

iOS: mWeb Safari

MacOS: Chrome / Safari

MacOS: Desktop

[melvin-bot]

@dukenv0307 Please copy/paste the Reviewer Checklist from here into a new comment on this PR and complete it. If you have the K2 extension, you can simply click: [this button]

[dukenv0307]

@aldo-expensify Can you please build the ad-hoc? cc @IuliiaHerets

[aldo-expensify]

@aldo-expensify Can you please build the ad-hoc? cc @IuliiaHerets

running

[github-actions]

🚧 @aldo-expensify has triggered a test app build. You can view the workflow run here.

[github-actions]

🧪🧪 Use the links below to test this adhoc build on Android, iOS, Desktop, and Web. Happy testing! 🧪🧪

Android 🤖	iOS 🍎
https://ad-hoc-expensify-cash.s3.amazonaws.com/android/58983/index.html	https://ad-hoc-expensify-cash.s3.amazonaws.com/ios/58983/index.html
Android Hybrid 🤖🔄	iOS Hybrid 🍎🔄
❌ FAILED ❌	❌ FAILED ❌
The QR code can't be generated, because the Android Hybrid build failed	The QR code can't be generated, because the iOS Hybrid build failed
Desktop 💻	Web 🕸️
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---

👀 View the workflow run that generated this build 👀

[dukenv0307]

any updates here?

[rinej]

@aldo-expensify where you able to test the build?

[aldo-expensify]

@aldo-expensify where you able to test the build?

No, given that @dukenv0307 asked for an ad-hoc build, I thought someone else was going to test this. I'll will try to test today.

[rinej]

thanks a lot @aldo-expensify :)

[aldo-expensify]

This is taking time for me because my dev environment somewhat broken

[aldo-expensify]

@dukenv0307 what is stopping you from testing this yourself?

[aldo-expensify]

The scrolling is working much better:

Screen.Recording.2025-04-01.at.12.26.24.PM.mov

I can now even reach the top of the conversation.

There seem to be a new issue though, if I try to go back, I see an error:

Screen.Recording.2025-04-01.at.12.27.38.PM.mov

I don't see this error if I do the same in main.

[dukenv0307]

I don't see that error on my side. Can you please take a look @rinej?

Screen.Recording.2025-04-02.at.10.54.21.mov

[rinej]

@aldo-expensify I couldn't reproduce it neither on main nor on the PR branch. Does this issue occurs regularly?

[aldo-expensify]

@aldo-expensify I couldn't reproduce it neither on main nor on the PR branch. Does this issue occurs regularly?

It was happening 100% of the time with that specific chat, I didn't try other chats. Did you try other chats?

[aldo-expensify]

I don't see that error on my side. Can you please take a look @rinej?

@dukenv0307 did you tap on the back button on the top left? I don't see that in your recording.

[aldo-expensify]

@rinej can you make sure your branch is up to date with main before I try to retest this again 🙏

[dukenv0307]

@aldo-expensify ah, you're right, I also can reproduce this bug but it's fixed after merging main

Screen.Recording.2025-04-03.at.14.20.17.mov

[aldo-expensify]

Thanks for checking @dukenv0307 , so we wait for @rinej to merge main and then we proceed with normal testing/review?

[dukenv0307]

Yes, @rinej can you please merge main, so I can do the checklists. Thanks

[rinej]

Sure, I merged it

[dukenv0307]

Reviewer Checklist

• I have verified the author checklist is complete (all boxes are checked off).
• I verified the correct issue is linked in the ### Fixed Issues section above
• I verified testing steps are clear and they cover the changes made in this PR
  • I verified the steps for local testing are in the Tests section
  • I verified the steps for Staging and/or Production testing are in the QA steps section
  • I verified the steps cover any possible failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
• I checked that screenshots or videos are included for tests on all platforms
• I included screenshots or videos for tests on all platforms
• I verified tests pass on all platforms & I tested again on:
  • Android: Native
  • Android: mWeb Chrome
  • iOS: Native
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
  • MacOS: Desktop
• If there are any errors in the console that are unrelated to this PR, I either fixed them (preferred) or linked to where I reported them in Slack
• I verified proper code patterns were followed (see Reviewing the code)
  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick).
  • I verified that the left part of a conditional rendering a React component is a boolean and NOT a string, e.g. myBool && <MyComponent />.
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text shown in the product is localized by adding it to src/languages/* files and using the translation method
  • I verified all numbers, amounts, dates and phone numbers shown in the product are using the localization methods
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I verified that this PR follows the guidelines as stated in the Review Guidelines
• I verified other components that can be impacted by these changes have been tested, and I retested again (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar have been tested & I retested again)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.js or at the top of the file that uses the constant) are defined as such
• If a new component is created I verified that:
  • A similar component doesn't exist in the codebase
  • All props are defined accurately and each prop has a /** comment above it */
  • The file is named correctly
  • The component has a clear name that is non-ambiguous and the purpose of the component can be inferred from the name alone
  • The only data being stored in the state is data necessary for rendering and nothing else
  • For Class Components, any internal methods passed to components event handlers are bound to this properly so there are no scoping issues (i.e. for onClick={this.submit} the method this.submit should be bound to this in the constructor)
  • Any internal methods bound to this are necessary to be bound (i.e. avoid this.submit = this.submit.bind(this); if this.submit is never passed to a component event handler like onClick)
  • All JSX used for rendering exists in the render method
  • The component has the minimum amount of code necessary for its purpose, and it is broken down into smaller components in order to separate concerns and functions
• If any new file was added I verified that:
  • The file has a description of what it does and/or why is needed at the top of the file if the code is not self explanatory
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG)
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• If a new page is added, I verified it's using the ScrollView component to make it scrollable when more elements are added to the page.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.
• I have checked off every checkbox in the PR reviewer checklist, including those that don't apply to this PR.

Screenshots/Videos

Android: Native

Screen.Recording.2025-02-20.at.22.19.38.mov

Android: mWeb Chrome

Screen.Recording.2025-02-20.at.22.15.02.mov

iOS: Native

Screen.Recording.2025-04-06.at.14.44.26.mov

iOS: mWeb Safari

Screen.Recording.2025-02-20.at.22.16.19.mov

MacOS: Chrome / Safari

Screen.Recording.2025-02-20.at.22.14.09.mov

MacOS: Desktop

Screen.Recording.2025-02-20.at.22.24.13.mov

[OSBotify]

✋ This PR was not deployed to staging yet because QA is ongoing. It will be automatically deployed to staging after the next production release.

[github-actions]

🚀 Deployed to staging by https://github.com/aldo-expensify in version: 9.1.24-2 🚀

platform	result
🖥 desktop 🖥	success ✅
🕸 web 🕸	success ✅
🤖 android 🤖	success ✅
🍎 iOS 🍎	success ✅

[github-actions]

🚀 Deployed to production by https://github.com/jasperhuangg in version: 9.1.24-10 🚀

platform	result
🖥 desktop 🖥	success ✅
🕸 web 🕸	success ✅
🤖 android 🤖	failure ❌
🍎 iOS 🍎	success ✅

[github-actions]

🚀 Deployed to production by https://github.com/jasperhuangg in version: 9.1.24-10 🚀

platform	result
🖥 desktop 🖥	success ✅
🕸 web 🕸	success ✅
🤖 android 🤖	failure ❌
🍎 iOS 🍎	success ✅