Hi, I have a problem with a component: if fails to rerender even though I think it should, how can I debug the situation?

@roti to help us help you, can you provide more information like a code snippet? A random guess is that you 1) not derefing a reagent atom in the component, or 2) the atom you are derefing is a normal clojurescript atom instead of a reagent atom, or 3) you are creating a reagent atom in the view ... but not doing so in a 'form-2' style and the atom is getting recreated every render

my deref is inside a for, is that a problem?

Wrap it in a doall

for is lazy, so it is possible that is a problem

https://github.com/reagent-project/reagent/issues/18

yep, that was the cause

i moved the deref in a top let and it works now

👍

I guess that reagent doesn't establish the link because at that time the render function is not yet executed

thanks for the link

Np

how can I trigger e re-render (for the on-load function from figwheel?

can I use the normal render method?

@roti in dev mode I believe reagent typically warns on deref ratoms in a for. It has at least some detection. Just curious if you didn’t have warnings show up.

I did not get a warning, but I don't know if I am in dev mode

@roti if you need to force a reload then calling the reagent/render function again is the best way to do that

@lee.justin.m thanks

doesn't seem to work when the rendering function has hanged

I probably need to tell reagent to render everything, not only those components whose ratom has changed

oh sorry, i thought you were manually hooking into some kind of hot reload signal, in which case you would just re-render the top level component in your tree

(defn mount-root []
  (reagent/render [top-level-component]
    (.getElementById js/document "app")))

that's what i'm doing

yea that will cause a remount. now you may still be experiencing some bugs like the one discussed above where the components do not reflect your data in a way that you expect

for is lazy

so shopping-list is not going to react to the atom

so wrap that for in a doall

next problem: line 10 of the snippet: you have a fn there that you don’t need and that doesn’t repeat the outer arguments. you should probably just remove it and do the destructuring right in the defn declaration

Thx justinlee! I’ll check them.

i am surprised that adding an item updates your components

It works now. Thank you! Yes, there is strange it worked for adding a new item or removing one it worked, but for updating one it didn’t.

But now It works well. Thx