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

Kurisu
Hello, Please, let’s say I have a website with user authentication made with Elixir/Phoenix, and now want to add a forum to it (using a ...
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
bsek43
Hello everyone, I’ve started learning Elixir and Phoenix few months ago and while I mostly grasped Elixir’s functional concepts and Phoe...
New
JimmyCarterSon
Hello, I am. very new to Elixir lang I have only been doing it for about 2 weeks. I recently started following this tutorial todo list, ...
New
Fl4m3Ph03n1x
Background So, I am playing around with a concept named “NewType” and I am taking inspiration from languages like F# and Scala. My objec...
New
Fl4m3Ph03n1x
Background I am moving towards defined data structures in my application, and I find that TypedStruct is quite useful. Questions Howeve...
New
sona11
I studied very basic PHP (I believe). After that, I feel like I’ve gotten a handle on the language. My dream is to work as a web develope...
New
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
Write Elixir tests that you can be proud of. Dive into Elixir’s test philosophy and gain mastery over the terminology and concepts that u...
New
AstonJ
SpaceVim seems to be gaining in features and popularity and I just wondered how it compares with SpaceMacs in 2020 - anyone have any thou...
New
Exadra37
Oh just spent so much time on this to discover now that RancherOS is in end of life but Rancher is refusing to mark the Github repo as su...
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
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
PragmaticBookshelf
Author Spotlight Mike Riley @mriley This month, we turn the spotlight on Mike Riley, author of Portable Python Projects. Mike’s book ...
New
New
New
PragmaticBookshelf
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New
mindriot
Ok, well here are some thoughts and opinions on some of the ergonomic keyboards I have, I guess like mini review of each that I use enoug...
New