add products edit function

app/controllers/admin/products_controller.rb

@@ -1,7 +1,7 @@
 class Admin::ProductsController < ApplicationController
   before_action :authenticate_user!
   before_action :admin_required
-  
+
   def index
     @products = Product.all
   end
@@ -20,6 +20,20 @@ def create
     end
   end
 
+  def edit
+    @product = Product.find(params[:id])
+  end
+
+  def update
+    @product = Product.find(params[:id])
+
+    if @product.update(product_params)
+      redirect_to admin_products_path
+    else
+      render :edit
+    end
+  end
+
   private
 
   def product_params

app/views/admin/products/edit.html.erb

@@ -0,0 +1,23 @@
+<h2> 新增產品 </h2>
+
+<%= simple_form_for [:admin, @product] do |f| %>
+
+  <div class="group">
+    <%= f.input :title %>
+  </div>
+
+  <div class="group">
+    <%= f.input :description %>
+  </div>
+
+  <div class="group">
+    <%= f.input :quantity %>
+  </div>
+
+  <div class="group">
+    <%= f.input :price %>
+  </div>
+
+  <%= f.submit "Submit", data: { disable_with: "Submitting..." } %>
+
+<% end %>