phoebe
Hi,
In my html.eex template form, I have a text_input form input and would like to pass to the placeholder a value based on some other field from the form (previously saved before form is rendered). I would like to do something like the following - have a :username field with a placeholder of the :first_name field value, but the placeholder variable is not recognised here:
<%= form_for @changeset, @action, fn f -> %>
<%= text_input f, :username, placeholder: :first_name %>
...
<% end %>
Is this possible to do with the text_input macro or do I need to use the tag macro? Thanks!
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kokolegorille
If You know the value of first_name, pass it as a variable in the controller…
:first_name is only an atom, pass it, and use it as @first_name.
If You want to use conditional rendering on the same form… You will need some JS skill… or LiveView, or Drab, or any server side libs that can potentially update DOM.
phoebe
Thanks, that makes complete sense - I was thinking that :first_name would auto-magically be available when the form ‘is loaded’
OvermindDL1
If you are wanting
:first_nameto pull from a key on your changeset/whatever namedfirst_namethen you can always do this:And that will compile the value in as the placeholder. If you want it to update ‘on the page’ then that’s a Javascript thing, so either a some javascript, drab, live_view, etc…
phoebe
Thanks! Very helpful indeed,
input_valueis easier than passing variable into a controller