I’m implementing a version of the autocompletion script found at
http://ricardo.pacheco.name/blog/articles/2006/07/26/using-
autocomplete-with-belongs_to-fields and have run into a stumbling
block.
The issue involves passing in a variable to indicate which custom
method should be invoked. I have an ugly workaround (a duplicate
function hardcoded to use the custom method), but would like to learn
a better way to handle this case. It feels like I’m missing something
simple, but I’ll be damned if I can see it.
from: app/helpers/application_helper.rb
def indexed_auto_complete_result(entries, entityType, field, index)
return unless entries
items = entries.map { |entry| content_tag(“li”, entry[field], “id”
=> entityType+‘::’+entry[index].to_s) }
content_tag(“ul”, items.uniq)
end
This works fine for referencing model attributes which exist in the
“Highlights” table (name, description, etc.) but fails if ‘field’ is
passed in as “name_with_place”. The unordered list is created, but
it’s full of empty
NoMethodError (undefined method ‘field’) errors in the log.
My eventual workaround was to add this function for those times I need
to access the name_with_place method. This works as desired, and
properly invokes the custom name_with_place method. It’s clearly not
DRY, though.
def indexed_auto_complete_result_with_place(entries, entityType,
field, index)
return unless entries
items = entries.map { |entry| content_tag(“li”,
entry.name_with_place, “id” => entityType+‘::’+entry[index].to_s)}
content_tag(“ul”, items.uniq)
end
from: app/models/highlight.rb
belongs_to :place
def name_with_place
if self.place.nil?
self.name
else
“#{self.name} (#{self.place.name})”
end
end
from: app/controllers/highlights_controller.rb
def auto_complete_for_highlight_internal_name
find_options = {
:conditions => [ “LOWER(name) LIKE ?”, ‘%’ +params[:highlight]
[:internal_name].downcase + ‘%’ ],
:order => “name ASC”,
:limit => 10
}
@highlights = Highlight.find(:all,find_options)
render :inline => “<%= indexed_auto_complete_result @highlights,
‘highlight_id’, ‘name_with_place’, ‘id’ %>”
end
from: public/javascripts/application.js
function auto_complete_on_select(element, selectedElement)
{
var entityParts = selectedElement.id.split(‘::’);
var entityType = entityParts[0];
var entityId = entityParts[1];
document.getElementById(entityType).value = entityId;
}
from: app/views/highlights/index.rhtml
<% form_tag(‘/highlights/edit’, :method => :post) do %>
<%= text_field_with_auto_complete :highlight, :internal_name, { :size
=> 40 }, { :after_update_element =>
‘auto_complete_and_redirect_on_select’ } %>
<%= hidden_field ‘highlight’, ‘id’ %>
<%= submit_tag(“Edit”) %>
<% end -%>