Administrate::Field::LatLng

Adds fields for displaying/editing latitude/longitude fields on a map to ThoughtBot's Administrate

Add this line to your application's Gemfile:

gem 'administrate-field-lat_lng'

And then execute:

$ bundle

In your dashboard's ATRRIBUTE_TYPES, use the type Field::LatLng with options:

ATTRIBUTE_TYPES = {
  lat: Field::LatLng,
  lng: Field::LatLng,
}

On show pages, you will now see a map directly below the lng field, which shows the location on a map. On edit pages, you can click this map to change the values of lat and lng in the form.

Important: Your lat and lng fields must appear in the right order (lat first) in SHOW_PAGE_ATTRIBUTES and FORM_ATTRIBUTES. This is because each field generates a piece of the final javascript so they must be evaluated in the correct order.

If your fields are not called lat and lng, you must specify options to make it clear which is which, e.g.:

ATTRIBUTE_TYPES = {
  latitude:  Field::LatLng.with_options({lat: true}),
  longitude: Field::LatLng.with_options({lng: true}),
}

Additional options that are available:

• initial: Set to an array like [53.8003,-1.5519]. Will cause the center of the map to be this point if the lat/lng have not yet been set (e.g. for new records). Defaults to Leeds, UK (because that's where the author is from).
• zoom: Set the default zoom level for maps drawn (defaults to 11).
• search: true (default) or false. Enable location search. Requires google_api_key option too.
• google_api_key: A key for the Google Maps JavaScript API. Required for location search to work.

This gem depends on being able to access cdnjs.cloudflare.com for the Leaflet JS and CSS. Let me know if you want this to change and be based on the asset pipeline.

Currently you can only have one pair of lat/lng per model type. Supporting multiple pairs would not be hard, so let me know if you need that functionality.

Bug reports and pull requests are welcome on GitHub at https://github.com/fishpercolator/administrate-field-lat_lng. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

The gem is available as open source under the terms of the MIT License.