mysql - how to disable submit button after being used 1 time -

what trying following.

a user.rb can answer.rb several application.rb's created company.rb. user can answer once per unique application.

i've disabled in model can't figure out how in view.

my answer controller:

class answerscontroller < applicationcontroller   before_action :authenticate_user!   def show   @application = application.find(params[:id])   @answer = answer.new end    def create   @answer = answer.new(answer_params.merge(:user_id => current_user.id)) if @answer.save   flash[:notice] = "you've applied"   redirect_to root_url else   flash[:alert] = "you've applied"   redirect_to root_url end end  private   def answer_params    params.require(:answer).permit(:answer_1, :answer_2, :answer_3, :application_id)    end  end 

in answer model have user_id stored. thinking @ current answer :id , check if current_user.id present in it, if disable button. haven't been able turned out successfully.

the show.html.erb looks this:

<%= form_for @answer |f| %>  <%= f.hidden_field :application_id, value: @application.id %>       <p>question 1: <%= @application.question_1 %></p>      <%= f.text_area :answer_1 %>      .......      <%= f.submit "submit" %>   <% end %> 

if use of jquery possible in ruby, you can use .one() method

.one( events [, selector ] [, data ], handler )                [jquery 1.7+]  events     type: string     1 or more space-separated event types , optional namespaces, such "click"      or "keydown.myplugin". selector     type: string     selector string filter descendants of selected elements trigger     event. if selector null or omitted, event triggered when     reaches selected element. data     type:     data passed handler in event.data when event triggered. handler type: function( event eventobject )     function execute when event triggered. value false allowed      shorthand function return false.