Remember dynamic select options in Rails - ruby-on-rails

Question

Models:
User create Event, and each Event need a Court location, then a House location, the value of House depends on the value of Court, for example:
select Court A, returns House as A1, A2, A3
select Court B, returns House as B1, B2, B3
In Event Controller form:
def new
#event = current_user.events.build(event_params)
#courts = Court.all
#houses = House.where("court_id = ?", Court.first.id)
end
def edit
#event = Event.find(params[:id])
#courts = Court.where(:id => #event.court_id)
#houses = House.where(:id => #event.house_id)
end
In View form:
<%= f.label 'Event Location' %>
<%= f.select :court_id, options_for_select(#courts.collect { |court| [court.name, court.id] }, 1), {}, { id: 'courts_select' } %>
<%= f.select :house_id, options_for_select(#houses.collect { |house| [house.name, house.id] }, 0), {}, { id: 'houses_select' } %>
Javascript:
$(function() {
return $(document).on('change', '#courts_select', function(evt) {
return $.ajax('/events/update_houses', {
type: 'GET',
dataType: 'script',
data: {
court_id: $("#courts_select option:selected").val()
},
error: function(jqXHR, textStatus, errorThrown) {
return console.log("AJAX Error: " + textStatus);
},
success: function(data, textStatus, jqXHR) {
return console.log("Dynamic court select OK!");
}
});
});
});
Now this works fine when the user create the event, but when they want to edit, the Court and House Select only shows 1 value. It's because in the edit controller the where() only returns 1 value. How can I change my edit controller code so that at edit form, it returns the a list of choices and remembers the user's choice

Answer 1

For starters, you want to supply all Courts and the corresponding Houses for the currently-selected Court.
def edit
#event = Event.find(params[:id])
#courts = Court.all
#houses = House.where(:court_id => #event.court_id)
end
Then you want your selects to select the proper value from the dropdown. Instead of:
<%= f.select :court_id, options_for_select(#courts.collect { |court| [court.name, court.id] }, 1), {}, { id: 'courts_select' } %>
Something like:
<%= f.select :court_id, options_for_select(#courts.collect { |court| [court.name, court.id] }, #event.court_id), {}, { id: 'courts_select' } %>
... rinse and repeat for the House select
Hope that helps!