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

chasekaylee
Hi there everyone! Recently, I have fallen in love with programming with Elixir and have been having so much fun with it. I have been do...
New
jaimeiniesta
I maintain a project that lists hundreds of thousands of web pages, and I’d like to show a screenshot for each web page. There are alread...
New
gagan7995
API 4 Path: /user/following/ Method: GET Description: Returns the list of all names of people whom the user follows Response [ { ...
New
Fl4m3Ph03n1x
Background I am trying to get a Github Action working with Windows and Bakeware because I am trying to create a release using it. Howeve...
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
Fl4m3Ph03n1x
Background I am a fan of dialyzer and friends (looking at Gradient) and I try to have sepcs in my code as much as I can. To this end, I a...
New
Fl4m3Ph03n1x
Background I have to queries that return a colossal amount of data on their own. I cannot use Repo.all as doing so would materialize thes...
New
pillaiindu
What is the difference between using :references and :belongs_to in the following command? bin/rails generate scaffold LineItem product:...
New
Patricia-Mendes13
Hi guys!! I´m studying and got a Full stack course but the course lacked a lot of support and and info to learn as it´s a course after wo...
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

PragmaticBookshelf
Take your Go skills to the next level by learning how to design, develop, and deploy a distributed service. Start from the bare essential...
New
siddhant3030
I’m thinking of buying a monitor that I can rotate to use as a vertical monitor? Also, I want to know if someone is using it for program...
New
brentjanderson
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
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
New
PragmaticBookshelf
Rust is an exciting new programming language combining the power of C with memory safety, fearless concurrency, and productivity boosters...
New
New
PragmaticBookshelf
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
PragmaticBookshelf
Develop, deploy, and debug BEAM applications using BEAMOps: a new paradigm that focuses on scalability, fault tolerance, and owning each ...
New