Rails scaffold with Bootstrap 4

_form.html.erb

<div class="page-header">
  <div class="row">
    <div class="col">
      <%%= link_to "All <%= plural_table_name.capitalize %>", <%= index_helper %>_path, class: 'btn btn-default' %>
    </div>
    <div class="col text-right">
      <%%= link_to "Edit", edit_<%= singular_table_name %>_path(@<%= singular_table_name %>), class: 'btn btn-primary' %>
    </div>
  </div>
  <h1>Show <%= singular_table_name %></h1>
</div>

<dl class="dl-horizontal">
  <%- attributes.each do |attribute| -%>
  <dt><%= attribute.human_name %>:</dt>
  <dd><%%= @<%= singular_table_name %>.<%= attribute.name %> %></dd>
  <%- end -%>
</dl>

edit.html.erb

<h1>Edit <%= singular_table_name.capitalize %></h1>

<%%= render 'form', <%= singular_table_name %>: @<%= singular_table_name %> %>

index.html.erb

<div class="row">
  <div class="col-sm-6">
    <h1><%= plural_table_name.capitalize %></h1>
  </div>

  <div class="col-sm-6 text-right">
    <%%= link_to "Add New <%= human_name %>", new_<%= singular_table_name %>_path, class: 'btn btn-primary' %>
  </div>
</div>

<div class="table-responsive">
  <table class="table table-hover">
    <thead>
      <tr>
        <%- attributes.each do |attribute| -%>
        <th><%= attribute.human_name %></th>
        <%- end -%>
        <th></th>
      </tr>
    </thead>

    <tbody>
      <%% @<%= plural_table_name%>.each do |<%= singular_table_name %>| %>
        <%%= content_tag :tr, id: dom_id(<%= singular_table_name %>), class: dom_class(<%= singular_table_name %>) do %>
          <%- attributes.each do |attribute| -%>
          <td><%%= <%= singular_table_name %>.<%= attribute.name %> %></td>
          <%- end -%>
          <td><%%= link_to 'Show', <%= singular_table_name %> %></td>
        <%% end %>
      <%% end %>
    </tbody>
  </table>
</div>

new.html.erb

<h1>New <%= singular_table_name %></h1>

<%%= render 'form', <%= singular_table_name %>: @<%= singular_table_name %> %>

show.html.erb

<div class="page-header">
  <div class="row">
    <div class="col">
      <%%= link_to "All <%= plural_table_name.capitalize %>", <%= index_helper %>_path, class: 'btn btn-default' %>
    </div>
    <div class="col text-right">
      <%%= link_to "Edit", edit_<%= singular_table_name %>_path(@<%= singular_table_name %>), class: 'btn btn-primary' %>
    </div>
  </div>
  <h1>Show <%= singular_table_name %></h1>
</div>

<dl class="dl-horizontal">
  <%- attributes.each do |attribute| -%>
  <dt><%= attribute.human_name %>:</dt>
  <dd><%%= @<%= singular_table_name %>.<%= attribute.name %> %></dd>
  <%- end -%>
</dl>

Copied from https://github.com/excid3/jumpstart with minor changes

Place those files in lib/templates/erb/scaffold

The index columns and form fields will be generated automatically from the scaffold command, example:

rails g scaffold user first_name:string last_name:string

Or just scaffold_controller

rails g scaffold_controller users first_name last_name