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
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
New
mrmurphy
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 socke...
New
TwistingTwists
Hello Folks, I am a novice developer from India. Intending to learn Elixir and web apps (phoenix framework). What are things that I MUS...
New
Fl4m3Ph03n1x
Background I am trying to encode a structure into json format using the Jason library. However, this is not working as expected. Code L...
New
sona11
In Java, if I try to do.equals() on a null string, a null pointer error is issued. I’m wondering whether I can perform the following if I...
New
Fl4m3Ph03n1x
Background I have a module that uses TypedStruct to create structs. This is the code: defmodule Shared.Data.Authorization do @moduledo...
New
Sumityadav
Hello all, I am new to learning Java Programming and want to learn java from scratch. I was writing a Java program to get the first and l...
New
Fl4m3Ph03n1x
Background As I often do, I read books to learn and improve myself. I also enjoy teaching and helping others when I can, so this is somet...
New

Other popular topics Top

AstonJ
If it’s a mechanical keyboard, which switches do you have? Would you recommend it? Why? What will your next keyboard be? Pics always w...
New
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
What chair do you have while working… and why? Is there a ‘best’ type of chair or working position for developers?
New
DevotionGeo
I know that these benchmarks might not be the exact picture of real-world scenario, but still I expect a Rust web framework performing a ...
New
Exadra37
I am thinking in building or buy a desktop computer for programing, both professionally and on my free time, and my choice of OS is Linux...
New
New
mafinar
Crystal recently reached version 1. I had been following it for awhile but never got to really learn it. Most languages I picked up out o...
New
Margaret
Hello everyone! This thread is to tell you about what authors from The Pragmatic Bookshelf are writing on Medium.
1147 28379 760
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
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New