title: "Could not find User without ID" ActiveRecord Error and editing trouble
body: <p>So I am having some trouble with my rails app and I think I went a little out of my own depth. I am creating a simple alumni application and I want users to be able to join organizations. For some reason in my new join page I get the error "Couldn't find User without an ID". I want to know why the ID isn't passing in, which would imply signed_in? = false. I don't know why everything worked find when I created other additions to my users controller but here it refuses to take on the logged in user id. I feel like I am missing something simple, let me know if updates are necessary!</p>
  
  <p>Here is the relevant information in my Users controller:</p>
  
  <pre><code>class UsersController &lt; ApplicationController
  before_action :signed_in_user, only: [:edit, :update, :index, :show, :join]
  before_action :correct_user,   only: [:edit, :update, :join]
  before_action :admin_user,     only: :destroy
  
  def join
  end
  
  def show
     @user = User.find(params[:id])
     @organization = @user.organization
  end
  
  def create
     @user = User.new(user_params)
     if @user.save
         sign_in @user
         flash[:success] = "Welcome to the Sample App!"
         redirect_to @user
    else
        render 'new'
    end
  end
  ...
        private
  
  def user_params
      params.require(:user).permit(:name,:email, :password, :password_confirmation,:organization_id)
  end
  
  
  def signed_in_user
    unless signed_in?
      store_location
      redirect_to signin_url, notice: "Please sign in."
    end
  end
  
  def correct_user
    @user = User.find(params[:id])
    redirect_to(root_url) unless current_user?(@user)
  end
  
  def admin_user
    redirect_to(root_url) unless current_user.admin?
  end
  end
  </code></pre>
  
  <p>I included the def create method because I tried editing it to redirect users to the join page right after login but then I came across this error and I thought that was the problem so i switched it back. I guess it wasnt.... NOTE: I am basing a lot of this app off of the Hartl tutorial if that is helpful.</p>