ActiveAdmin - Filter with default value - activeadmin

Question

Would like to know is that possible to have filter with default value with active admin? This will be helpful for preloading the data for the admin user.
filter :country, :default=>'US'

Answer 1

You can do it by defining before_filter
before_filter :only => [:index] do
if params['commit'].blank?
#country_contains or country_eq .. or depending of your filter type
params['q'] = {:country_eq => 'US'}
end
end
UPD:
in some cases you need to set filter if params[:q] is empty or params[:scope] empty
so this might work better
before_filter :only => [:index] do
if params['commit'].blank? && params['q'].blank? && params[:scope].blank?
#country_contains or country_eq .. or depending of your filter type
params['q'] = {:country_eq => 'US'}
end
end

Answer 2

Adapted Fivells answer to work correctly with scopes and downloads. Feels hacky but seems to do the job. Annotated intention in comments.
before_filter only: :index do
# when arriving through top navigation
if params.keys == ["controller", "action"]
extra_params = {"q" => {"country_eq" => "US"}}
# make sure data is filtered and filters show correctly
params.merge! extra_params
# make sure downloads and scopes use the default filter
request.query_parameters.merge! extra_params
end
end

Answer 3

Fixing issue with "Clear Filters" button breaking, updated answer building on previous answers:
Rails now uses before_action instead of before_filter. It belongs in the controller like so:
ActiveAdmin.register User do
controller do
before_action :set_filter, only: [:index]
def set_filter
# when arriving through top navigation
if params.keys == ["controller", "action"]
extra_params = {"q" => {"country_eq" => "US"}}
# make sure data is filtered and filters show correctly
params.merge! extra_params
# make sure downloads and scopes use the default filter
request.query_parameters.merge! extra_params
end
end
params.delete("clear_filters") #removes "clear_filters" if it exists to clear it out when not needed
end
end
Note, ActiveAdmin uses ransack for queries (ex. {"q" => {"country_eq" => "US"}}), check out https://activerecord-hackery.github.io/ransack/getting-started/search-matches for more matches if you need something more complex than "_eq".
Also, previous answers leave the "Clear Filters" button broken. It doesn't clear the filters, the filters set here are simply re-applied.
To fix the "Clear Filters" button, I used this post as a guide How to keep parameters after clicking clear filters in ActiveAdmin.
#app/assets/javascripts/active_admin.js
# Making clear filter button work even on pages with default filters
$ ->
$('.clear_filters_btn').click ->
if !location.search.includes("clear_filters=true")
location.search = "clear_filters=true"
This removes all search params (ie filters) and adds "clear_filters=true" so the controller can tell the request came from the "Clear Filters" button.

Answer 4

before_action only: [:index] do
if params['commit'].blank?
extra_params = {"country_eq" => "US"}
params['q'] = {} if params['q'].blank?
params['q'].merge! extra_params
request.query_parameters.merge! extra_params
end
end