In the PostStream, `this.visibleEnd` represents the index of the last post + 1, but `loadNearIndex` treated it as if it was the index of the last post. This means that executing `goToIndex` on the post stream's current `this.visiblePost` didn't load new posts, and as a result, the requested scrolling did not occur.
- Add an index to reply placeholder so we can scroll to it directly when replying.
- Stop pretending that the currently broken `bottom` scroll functionality works, and explicitly call it `reply` scrolling to be clearer
- Directly get target from state
- Explicitly scroll to placeholder on reply
- Clean up scrollToItem code a bit
- Account for edge case where index is undefined when scrolling to post
Co-authored-by: Wadim Kalmykov <36057469+w-4@users.noreply.github.com>
While more pleasant from an FSM standpoint, comparing the current targetPost to the previous one does not work if goToNumber is called twice in a row for the same post. For instance, if a user clicks the mentions link to a post twice, the post stream breaks.
In some cases, such as if we've stickied a post, an event post
may have been added / removed.This means that `this.visibleEnd`
and`this.count()` will be out of sync by 1 post, but we are still
"viewing the end" of the post stream, so we should still reload
all posts up until the last one.
When the page is scrolled, goToIndex is called, or the page is loaded,
various listeners result in the scrubber being updated with a new
position and values. However, if goToNumber is called, the scrubber
will not be updated. Accordingly, we add logic to the scrubber's
onupdate to update itself, but only when needed, as indicated by this
This saves us a LOT of unnecessary calls, and makes scrubber movement smoother.
* Update frontend to Mithril 2
- Update Mithril version to v2.0.4
- Add Typescript typings for Mithril
- Rename "props" to "attrs"; "initProps" to "initAttrs"; "m.prop" to "m.stream"; "m.withAttr" to "utils/withAttr".
- Use Mithril 2's new lifecycle hooks
- SubtreeRetainer has been rewritten to be more useful for the new system
- Utils for forcing page re-initializations have been added (force attr in links, setRouteWithForcedRefresh util)
- Other mechanical changes, following the upgrade guide
- Remove some of the custom stuff in our Component base class
- Introduce "fragments" for non-components that control their own DOM
- Remove Mithril patches, introduce a few new ones (route attrs in <a>;
- Redesign AlertManagerState `show` with 3 overloads: `show(children)`, `show(attrs, children)`, `show(componentClass, attrs, children)`
- The `affixedSidebar` util has been replaced with an `AffixedSidebar` component
Challenges:
- `children` and `tag` are now reserved, and can not be used as attr names
- Behavior of links to current page changed in Mithril. If moving to a page that is handled by the same component, the page component WILL NOT be re-initialized by default. Additional code to keep track of the current url is needed (See IndexPage, DiscussionPage, and UserPage for examples)
- Native Promise rejections are shown on console when not handled
- Instances of components can no longer be stored. The state pattern should be used instead.
Refs #1821.
Co-authored-by: Alexander Skvortsov <sasha.skvortsov109@gmail.com>
Co-authored-by: Matthew Kilgore <tankerkiller125@gmail.com>
Co-authored-by: Franz Liedke <franz@develophp.org>