That was my first attempt, as my resource preloads the tags, however live select errors out because it requires that the selected values are:
atoms, strings or numbers, maps or keywords with keys: (:label, :value) or (:key, :value) and an optional key :tag_label
2-element tuples
And they are not because they are structs like %Tag{}.
And they are not because they are structs like
%Tag{}.
then you should convert them 
Enum.map/2 is your friend here.
I mean, what would you do if it was an ordinary select?
The select case is a little different because there is a 1:1 mapping only but I got your point, and it helped me find the solution. I was able to simplify my form by having the current tags mapped as two-element tuple in the to_form from the changeset. Then, before saving, as the params will only contain the id and name, I can have a lookup, and set the tags for the internal API that uses Ecto put_assoc.
Thanks for your help.
Great! Glad it worked out.
I should probably add an example in the docs that explains this kind of scenario.
Is there a way we can handle many_to_many relations as described in Polymorphic associations with many to many — Ecto v3.14.0?
Thanks. LiveSelect isn’t sending events to the FormComponent, instead they are being sent to the parent live_view inspite of having a phx-target:
.in FormComponent
<.live_select
phx-target={@myself}
field={@form[:tags]}
mode={:tags}
/>
in index.html.heex
<.live_component module={FormComponent} />
Here :tags is a many_to_many with a
cast_assoc(:tags, with: &Tag.changeset/2)
in the parent schema. Any idea what I am missing?
I don’t see anything wrong here. Which event are we talking about, the live_select_change event or the form’s phx-change event? Is phx-target also set in the form?
More code would be helpful.
phx-target is set on form-element as well.
<.simple_form
for={@form}
id="prompt-form"
phx-target={@myself}
phx-change="validate"
phx-submit="save"
>
<.input field={@form[:text]} type="textarea" label="Prompt" />
<.live_select
phx-target={@myself}
field={@form[:tags]}
mode={:tags}
style={:tailwind}
value={Enum.map(@form[:tags].value, &{&1.name, &1.id})}
options={[{"Legal", 1}, {"Vendors", 2}]}
/>
<:actions>
<.button intent="primary" phx-disable-with="Saving...">Save Prompt</.button>
</:actions>
</.simple_form>
The above code actually errors out with:
invalid element in selection: %Tag{__meta__: ..
If I change to field={@form[:tag]} (tag is a virtual field) it works but it sends the events to the parent index:
[debug] HANDLE EVENT "change" in PromptLive.Index
Component: LiveSelect.Component
Parameters: %{"_target" => ["prompt", "tag_text_input"], "prompt" => %{"tag_text_input" => "s"}}
[debug] Replied in 484µs
[debug] HANDLE EVENT "blur" in PromptLive.Index
Component: LiveSelect.Component
Parameters: %{"value" => "s"}
[debug] Replied in 2ms
You say you expect the events to be sent to a LiveComponent and not to the parent LiveView.
Where is this LiveComponent?