Add several layout hooks to provide extra content (#2574)

This commit allows us to add content in some additional places, from
around the header to around the main body, which means users can more
easily customise their templates without needing to override the whole
file.

app/views/administrate/application/_index_header.html.erb

@@ -7,6 +7,8 @@
     <%= content_for(:title) %>
   </h1>
 
+  <%= content_for(:header_middle) %>
+
   <% if show_search_bar %>
     <%= render(
       "search",
@@ -25,4 +27,6 @@
       class: "button",
     ) if accessible_action?(new_resource, :new) %>
   </div>
+
+  <%= content_for(:header_last) %>
 </header>

app/views/administrate/application/edit.html.erb

@@ -22,15 +22,27 @@ It displays a header, and renders the `_form` partial to do the heavy lifting.
     <%= content_for(:title) %>
   </h1>
 
+  <%= content_for(:header_middle) %>
+
   <div>
     <%= link_to(
       t("administrate.actions.show_resource", name: page.page_title),
       [namespace, page.resource],
       class: "button",
     ) if accessible_action?(page.resource, :show) %>
   </div>
+
+  <%= content_for(:header_last) %>
 </header>
 
-<section class="main-content__body">
-  <%= render "form", page: page %>
-</section>
+<%= content_for(:before_main) %>
+
+<% if content_for?(:main) %>
+  <%= content_for(:main) %>
+<% else %>
+  <section class="main-content__body">
+    <%= render "form", page: page %>
+  </section>
+<% end %>
+
+<%= content_for(:after_main) %>

app/views/administrate/application/index.html.erb

@@ -32,15 +32,23 @@ It renders the `_table` partial to display details about the resources.
   )
 %>
 
-<section class="main-content__body main-content__body--flush">
-  <%= render(
-    "collection",
-    collection_presenter: page,
-    collection_field_name: resource_name,
-    page: page,
-    resources: resources,
-    table_title: "page-title"
-  ) %>
+<%= content_for(:before_main) %>
+
+<% if content_for?(:main) %>
+  <%= content_for(:main) %>
+<% else %>
+  <section class="main-content__body main-content__body--flush">
+    <%= render(
+      "collection",
+      collection_presenter: page,
+      collection_field_name: resource_name,
+      page: page,
+      resources: resources,
+      table_title: "page-title"
+    ) %>
+
+    <%= render("pagination", resources: resources) %>
+  </section>
+<% end %>
 
-  <%= render("pagination", resources: resources) %>
-</section>
+<%= content_for(:after_main) %>

app/views/administrate/application/new.html.erb

@@ -27,11 +27,23 @@ to do the heavy lifting.
     <%= content_for(:title) %>
   </h1>
 
+  <%= content_for(:header_middle) %>
+
   <div>
     <%= link_to t("administrate.actions.back"), :back, class: "button" %>
   </div>
+
+  <%= content_for(:header_last) %>
 </header>
 
-<section class="main-content__body">
-  <%= render "form", page: page %>
-</section>
+<%= content_for(:before_main) %>
+
+<% if content_for?(:main) %>
+  <%= content_for(:main) %>
+<% else %>
+  <section class="main-content__body">
+    <%= render "form", page: page %>
+  </section>
+<% end %>
+
+<%= content_for(:after_main) %>

app/views/administrate/application/show.html.erb

@@ -23,6 +23,8 @@ as well as a link to its edit page.
     <%= content_for(:title) %>
   </h1>
 
+  <%= content_for(:header_middle) %>
+
   <div>
     <%= link_to(
       t("administrate.actions.edit_resource", name: page.page_title),
@@ -38,28 +40,38 @@ as well as a link to its edit page.
       data: { turbo_confirm: t("administrate.actions.confirm") }
     ) if accessible_action?(page.resource, :destroy) %>
   </div>
+
+  <%= content_for(:header_last) %>
 </header>
 
-<section class="main-content__body">
-  <dl>
-    <% page.attributes.each do |title, attributes| %>
-      <fieldset class="<%= "field-unit--nested" if title.present? %>">
-        <% if title.present? %>
-          <legend><%= t "helpers.label.#{page.resource_name}.#{title}", default: title %></legend>
-        <% end %>
+<%= content_for(:before_main) %>
+
+<% if content_for?(:main) %>
+  <%= content_for(:main) %>
+<% else %>
+  <section class="main-content__body">
+    <dl>
+      <% page.attributes.each do |title, attributes| %>
+        <fieldset class="<%= "field-unit--nested" if title.present? %>">
+          <% if title.present? %>
+            <legend><%= t "helpers.label.#{page.resource_name}.#{title}", default: title %></legend>
+          <% end %>
+
+          <% attributes.each do |attribute| %>
+            <dt class="attribute-label" id="<%= attribute.name %>">
+            <%= t(
+              "helpers.label.#{resource_name}.#{attribute.name}",
+              default: page.resource.class.human_attribute_name(attribute.name),
+            ) %>
+            </dt>
 
-        <% attributes.each do |attribute| %>
-          <dt class="attribute-label" id="<%= attribute.name %>">
-          <%= t(
-            "helpers.label.#{resource_name}.#{attribute.name}",
-            default: page.resource.class.human_attribute_name(attribute.name),
-          ) %>
-          </dt>
+            <dd class="attribute-data attribute-data--<%=attribute.html_class%>"
+                ><%= render_field attribute, page: page %></dd>
+          <% end %>
+        </fieldset>
+      <% end %>
+    </dl>
+  </section>
+<% end %>
 
-          <dd class="attribute-data attribute-data--<%=attribute.html_class%>"
-              ><%= render_field attribute, page: page %></dd>
-        <% end %>
-      </fieldset>
-    <% end %>
-  </dl>
-</section>
+<%= content_for(:after_main) %>

docs/customizing_page_views.md

@@ -94,3 +94,28 @@ rails generate administrate:views:layout
  # It only generates the sidebar partial
  # -> app/views/admin/application/_navigation.html.erb
 ```
+
+## Customizing for a specific layout
+
+You can use several hook points to add elements to specific layouts or specific pages:
+
+* header_middle
+* header_last
+* before_main
+* main
+* after_main
+
+For example, you can add a button in the middle of the header as follows:
+
+```eruby
+<%# app/views/admin/customers/_index_header.html.erb %>
+
+<% content_for(:header_middle) do %>
+  <div>
+    You are logged in as <em><%= pundit_user.name %></em>.
+    <%= link_to("Become the Admin", become_admin_customer_path("admin")) unless pundit_user.admin? %>
+  </div>
+<% end %>
+
+<%= render template: 'administrate/application/_index_header', locals: local_assigns %>
+```

spec/example_app/app/views/admin/customers/_index_header.html.erb

@@ -1,33 +1,8 @@
-<% content_for(:title) do %>
-  <%= display_resource_name(page.resource_name) %>
-<% end %>
-
-<header class="main-content__header">
-  <h1 class="main-content__page-title" id="page-title">
-    <%= content_for(:title) %>
-  </h1>
-
+<% content_for(:header_middle) do %>
   <div>
     You are logged in as <em><%= pundit_user.name %></em>.
     <%= link_to("Become the Admin", become_admin_customer_path("admin")) unless pundit_user.admin? %>
   </div>
+<% end %>
 
-  <% if show_search_bar %>
-    <%= render(
-      "search",
-      search_term: search_term,
-      resource_name: display_resource_name(page.resource_name)
-    ) %>
-  <% end %>
-
-  <div>
-    <%= link_to(
-      t(
-        "administrate.actions.new_resource",
-        name: display_resource_name(page.resource_name, singular: true).downcase
-      ),
-      [:new, namespace, page.resource_path.to_sym],
-      class: "button",
-    ) if accessible_action?(new_resource, :new) %>
-  </div>
-</header>
+<%= render template: 'administrate/application/_index_header', locals: local_assigns %>