Question

In try to use gmaps4rails in my ActiveAdmin / Rails app. To do so, I have added the following in my Gemfile:

gem 'gmaps4rails'

and ran a “bundle”. I updated the ‘show’ method in app/admin/device.rb file with:

show do 
  attributes_table do
    row :name
  end

  # Get device location
  @markers = Location.all.to_gmaps4rails
  div do
    render "map"
  end
end

In the app/views/admin/devices/_map.html.erb I have the following code:

<%= stylesheet_link_tag 'gmaps4rails' %>
<%= gmaps4rails(@markers) %>
<%= yield :scripts %>

In app/assets/javascripts/application.js:

//= require gmaps4rails/gmaps4rails.googlemaps
//= require gmaps4rails/gmaps4rails.base
//= require jquery
//= require jquery_ujs
//= require_tree .

And in my app/models/location.rb:

class Location < ActiveRecord::Base
  acts_as_gmappable

  attr_accessible :latitude, :longitude

  def gmaps4rails_address
    "#{self.latitude}, #{self.longitude}" 
  end

  def location
    [:latitude, :longitude]
  end
end

When I go on the show page of a device, the map does not shows up (all blank). Is there any configuration I missed ?

UPDATE

I have checked with chrome developer tools and noticed the following error:

Uncaught SyntaxError: Unexpected token ;

that make reference to the line:

Gmaps.map.markers = ;

Answer 1

Fix with the following:

div do
  markers = Location.all.to_gmaps4rails
  render "map", { :markers => markers }
end

and :

<%= stylesheet_link_tag 'gmaps4rails' %>
<%= gmaps({
        "map_options" => { "zoom" => 2, "auto_adjust" => false},
        "markers"     => { "data" => markers }
        })
%>
<%= yield :scripts %>