mrmurphy

mrmurphy

How exactly does phx-update detect changes?

I’ve run into a situation where I’ve got a list of posts inside of a container that uses phx-update=“prepend”, and the posts on the socket are temporary assigns. Inside of the “for” comprehension, I want to render data not only from the post, but from another assign on the socket.

When the post changes, my DOM updates render, but when the other assign I’m using (pending_loves, in the image) changes, I don’t get any DOM updates. I’m guessing this is because live view is doing some magic change tracking around the for comprehension specifically? What’s the most idiomatic way to inform Live View that I want the content inside of the for to update when a different assign changes as well?

Most Liked

mrmurphy

mrmurphy

Thanks! Victor Mono:

dimitarvp

dimitarvp

Thank you! Instant switch in my terminal programs. Can’t believe I missed it even though I have it in my library.

Previously used InconsolataGo but Victor Mono is definitely better. :slight_smile:

mrmurphy

mrmurphy

I thought maybe if I included the pending_loves assign on the right-hand side of the for comprehension, the change would be picked up and re-rendered. But no dice:

  <div id="posts" class="max-w-lg mx-auto dark:bg-gray-800" phx-update="prepend">
    <%= for {post, pending_loves} <- (@posts|>Enum.map(&({&1, get_pending_loves(@pending_loves, &1.id)}))) do %>
    <div id="<%= post.id %>">

Even with this change, when I update the assign @pending_loves, the count of pending loves does not update on the page inside of the for comprehension until the post object is updated. It does update if placed outside of the comprehension, though, even inside of the phx-update="prepend" container.

Where Next?

Popular Backend topics Top

Rainer
Is there somewhere a good introduction to rust for experienced programmers (with years of C++/C#/Java experience)? Wanted to give it a t...
New
IhorYachmenov
Hello. I have an iOS app where needs a proxying website through private server(HTTP / HTTPS proxy), but its idea each time has some trou...
New
Kurisu
Hello and happy new year! I would like to buy a Ruby On Rails ebook for learning purpose. What would be the ROR equivalent of “Programm...
New
Jsdr3398
Are there any databases that require no setup (can be shipped in a small zip together with the project)?
New
New
gagan7995
API 4 Path: /user/following/ Method: GET Description: Returns the list of all names of people whom the user follows Response [ { ...
New
Ookma-Kyi
I am learning Elixir at the moment but am finding it difficult to learn. The issue is there aren’t any good tutorial sites out there when...
New
JimmyCarterSon
Hello, I am working on a new application with Elixir, Dish_out. I want to see Data I follow this tutorial with Elixir Casts. However, I ...
New
AstonJ
If when trying to create (or recreate) your dev db with rails db:create you are getting: PG::ConnectionBad: connection to server on soc...
New
Shiny
Hey community, this is my first post here so I will try to be as concise as possible and I appreciate any feedback. I’ve been writing Ro...
New

Other popular topics Top

ohm
Which, if any, games do you play? On what platform? I just bought (and completed) Minecraft Dungeons for my Nintendo Switch. Other than ...
New
AstonJ
poll poll Be sure to check out @Dusty’s article posted here: An Introduction to Alternative Keyboard Layouts It’s one of the best write-...
New
AstonJ
In case anyone else is wondering why Ruby 3 doesn’t show when you do asdf list-all ruby :man_facepalming: do this first: asdf plugin-upd...
New
AstonJ
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
PragmaticBookshelf
Build efficient applications that exploit the unique benefits of a pure functional language, learning from an engineer who uses Haskell t...
New
First poster: AstonJ
Jan | Rethink the Computer. Jan turns your computer into an AI machine by running LLMs locally on your computer. It’s a privacy-focus, l...
New
PragmaticBookshelf
Get the comprehensive, insider information you need for Rails 8 with the new edition of this award-winning classic. Sam Ruby @rubys ...
New
PragmaticBookshelf
Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...
New
AstonJ
This is a very quick guide, you just need to: Download LM Studio: https://lmstudio.ai/ Click on search Type DeepSeek, then select the o...
New
NewsBot
Node.js v22.14.0 has been released. Link: Release 2025-02-11, Version 22.14.0 'Jod' (LTS), @aduh95 · nodejs/node · GitHub
New