I'm facing a challenge where I need to update a Ruby on Rails partial within a view using a JavaScript object-defined variable, but I'm struggling to make it work. Despite my research pointing towards using an Ajax call as the only viable solution, I'm having trouble understanding why this is necessary (considering the JavaScript variable is already available before the Rails command) and how exactly to go about implementing it.
Within my Rails view, there is a section of HTML code that I aim to modify:
<div id="myevent">
<% if @pocket.events.any? %>
<%= @event = @pocket.events.first %>
<%= render @event %>
<% end %>
</div>
In the same view, I've integrated a JavaScript object consisting of clickable nodes, each representing a unique event with an individual identifier. My objective is to refresh the #myevent section above whenever a user clicks on a different node.
Being new to front-end development, I've attempted the following approach:
timeline.on('click', function (properties) {
logEvent('click', properties);
var item = properties["item"];
$('#myevent').html("<%= escape_javascript render (@pocket.events.find_by id:" + item + ") %>");
The JavaScript variable 'item' contains the event id from the clicked node. However, the last line in the snippet above results in an ArgumentError being raised by Rails with the message:
'nil' is not an ActiveModel-compatible object. It must implement :to_partial_path.
To my surprise, the code does function properly when I hardcode an id, indicating that the logic behind my approach is correct:
$('#myevent').html("<%= escape_javascript render (@pocket.events.find_by id: 5) %>");
I also experimented with utilizing a partial format:
$('#event').html("<%= escape_javascript render :partial=>'shared/event', :locals=> {event_id: " + item + "} %>")
And then tried fetching the appropriate event in the 'shared/event' partial using the method below:
<%= @event = Event.find(event_id) %>
Unfortunately, this resulted in an ActiveRecord::RecordNotFound error as it failed to replace the string "+ item +" with the value of the JavaScript variable:
Couldn't find Event with 'id'=+item+
The main issue persists – I am unable to successfully incorporate the JavaScript-defined variable into these Rails calls. It seems like resorting to an Ajax call is the most feasible solution, but despite numerous attempts, I haven't been able to resolve this independently. Any assistance would be greatly appreciated.