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Diffstat (limited to 'railties/guides/source/getting_started.textile')
| -rw-r--r-- | railties/guides/source/getting_started.textile | 52 |
1 files changed, 33 insertions, 19 deletions
diff --git a/railties/guides/source/getting_started.textile b/railties/guides/source/getting_started.textile index 7c029762a3..c15d6aa8ab 100644 --- a/railties/guides/source/getting_started.textile +++ b/railties/guides/source/getting_started.textile @@ -87,7 +87,7 @@ Action Mailer is a framework for building e-mail services. You can use Action Ma h5. Active Resource -Active Resource provides a framework for managing the connection between business objects an RESTful web services. It implements a way to map web-based resources to local objects with CRUD semantics. +Active Resource provides a framework for managing the connection between business objects and RESTful web services. It implements a way to map web-based resources to local objects with CRUD semantics. h5. Railties @@ -154,7 +154,7 @@ And if you’re using PostgreSQL for data storage, run this command: $ rails blog -d postgresql </shell> -TIP. You can see all of the switches that the Rails application builder accepts by running <tt>rails -h</tt>. +TIP: You can see all of the switches that the Rails application builder accepts by running <tt>rails -h</tt>. After you create the blog application, switch to its folder to continue work directly in that application: @@ -259,7 +259,7 @@ One of the traditional places to start with a new language is by getting some te $ script/generate controller home index </shell> -TIP. If you're on Windows, or your Ruby is set up in some non-standard fashion, you may need to explicitly pass Rails +script+ commands to Ruby: +ruby script/generate controller home index+. +TIP: If you're on Windows, or your Ruby is set up in some non-standard fashion, you may need to explicitly pass Rails +script+ commands to Ruby: +ruby script/generate controller home index+. Rails will create several files for you, including +app/views/home/index.html.erb+. This is the template that will be used to display the results of the +index+ action (method) in the +home+ controller. Open this file in your text editor and edit it to contain a single line of code: @@ -279,7 +279,7 @@ This will fire up an instance of the Mongrel web server by default (Rails can al !images/rails_welcome.png(Welcome Aboard screenshot)! -TIP. To stop the web server, hit Ctrl+C in the terminal window where it's running. In development mode, Rails does not generally require you to stop the server; changes you make in files will be automatically picked up by the server. +TIP: To stop the web server, hit Ctrl+C in the terminal window where it's running. In development mode, Rails does not generally require you to stop the server; changes you make in files will be automatically picked up by the server. The "Welcome Aboard" page is the _smoke test_ for a new Rails application: it makes sure that you have your software configured correctly enough to serve a page. To view the page you just created, navigate to +http://localhost:3000/home/index+. @@ -400,7 +400,7 @@ Now you're ready to start working with posts. To do that, navigate to +http://lo This is the result of Rails rendering the +index+ view of your posts. There aren't currently any posts in the database, but if you click the +New Post+ link you can create one. After that, you'll find that you can edit posts, look at their details, or destroy them. All of the logic and HTML to handle this was built by the single +script/generate scaffold+ command. -TIP. In development mode (which is what you're working in by default), Rails reloads your application with every browser request, so there's no need to stop and restart the web server. +TIP: In development mode (which is what you're working in by default), Rails reloads your application with every browser request, so there's no need to stop and restart the web server. Congratulations, you're riding the rails! Now it's time to see how it all works. @@ -461,7 +461,7 @@ The easiest place to start looking at functionality is with the code that lists <ruby> def index - @posts = Post.find(:all) + @posts = Post.all respond_to do |format| format.html # index.html.erb @@ -486,7 +486,7 @@ The +respond_to+ block handles both HTML and XML calls to this action. If you br <th>Content</th> </tr> -<% for post in @posts %> +<% @posts.each do |post| %> <tr> <td><%=h post.name %></td> <td><%=h post.title %></td> @@ -510,7 +510,7 @@ This view iterates over the contents of the +@posts+ array to display content an * +link_to+ builds a hyperlink to a particular destination * +edit_post_path+ is a helper that Rails provides as part of RESTful routing. You’ll see a variety of these helpers for the different actions that the controller includes. -TIP. For more details on the rendering process, see "Layouts and Rendering in Rails":layouts_and_rendering.html. +TIP: For more details on the rendering process, see "Layouts and Rendering in Rails":layouts_and_rendering.html. h4. Customizing the Layout @@ -582,7 +582,7 @@ The +new.html.erb+ view displays this empty Post to the user: <%= link_to 'Back', posts_path %> </erb> -The +form_for+ block is used to create an HTML form. Within this block, you have access to methods to build various controls on the form. For example, +f.text_field :name+ tells Rails to create a text input on the form, and to hook it up to the +name+ attribute of the instance being displayed. You can only use these methods with attributes of the model that the form is based on (in this case +name+, +title+, and +content+). Rails uses +form_for+ in preference to having your write raw HTML because the code is more succinct, and because it explicitly ties the form to a particular model instance. +The +form_for+ block is used to create an HTML form. Within this block, you have access to methods to build various controls on the form. For example, +f.text_field :name+ tells Rails to create a text input on the form, and to hook it up to the +name+ attribute of the instance being displayed. You can only use these methods with attributes of the model that the form is based on (in this case +name+, +title+, and +content+). Rails uses +form_for+ in preference to having you write raw HTML because the code is more succinct, and because it explicitly ties the form to a particular model instance. TIP: If you need to create an HTML form that displays arbitrary fields, not tied to a model, you should use the +form_tag+ method, which provides shortcuts for building forms that are not necessarily tied to a model instance. @@ -609,7 +609,7 @@ end The +create+ action instantiates a new Post object from the data supplied by the user on the form, which Rails makes available in the +params+ hash. After saving the new post, it uses +flash[:notice]+ to create an informational message for the user, and redirects to the show action for the post. If there's any problem, the +create+ action just shows the +new+ view a second time, with any error messages. -Rails provides the +flash+ hash (usually just called the Flash) so that messages can be carried over to another action, providing the user with useful information on the status of their request. In the case of +create+, the user never actually sees any page rendered during the Post creation process, because it immediately redirects to the new Post as soon Rails saves the record. The Flash carries over a message to the next action, so that when the user is redirected back to the +show+ action, they are presented with a message saying "Post was successfully created." +Rails provides the +flash+ hash (usually just called the Flash) so that messages can be carried over to another action, providing the user with useful information on the status of their request. In the case of +create+, the user never actually sees any page rendered during the Post creation process, because it immediately redirects to the new Post as soon Rails saves the record. The Flash carries over a message to the next action, so that when the user is redirected back to the +show+ action, they are presented with a message saying "Post was successfully created." h4. Showing an Individual Post @@ -785,7 +785,7 @@ As you saw earlier, the scaffold-generated views for the +new+ and +edit+ action Now, when Rails renders the +new+ or +edit+ view, it will insert the +_form+ partial at the indicated point. Note the naming convention for partials: if you refer to a partial named +form+ inside of a view, the corresponding file is +_form.html.erb+, with a leading underscore. -For more information on partials, refer to the "Layouts and Rending in Rails":layouts_and_rendering.html guide. +For more information on partials, refer to the "Layouts and Rendering in Rails":layouts_and_rendering.html#using-partials guide. h4. Using Filters to Eliminate Controller Duplication @@ -954,7 +954,7 @@ With the model in hand, you can turn your attention to creating a matching contr $ script/generate controller Comments index show new edit </shell> -This creates seven files: +This creates eight files: * +app/controllers/comments_controller.rb+ - The controller * +app/helpers/comments_helper.rb+ - A view helper file @@ -963,6 +963,7 @@ This creates seven files: * +app/views/comments/new.html.erb+ - The view for the new action * +app/views/comments/edit.html.erb+ - The view for the edit action * +test/functional/comments_controller_test.rb+ - The functional tests for the controller +* +test/unit/helpers/comments_helper_test.rb+ - The unit tests for the helper The controller will be generated with empty methods and views for each action that you specified in the call to +script/generate controller+: @@ -1031,11 +1032,7 @@ class CommentsController < ApplicationController @post = Post.find(params[:post_id]) @comment = Comment.find(params[:id]) @comment.destroy - - respond_to do |format| - format.html { redirect_to post_comments_path(@post) } - format.xml { head :ok } - end + redirect_to post_comments_path(@post) end end @@ -1198,6 +1195,22 @@ As a next step, I'll modify the +views/posts/show.html.erb+ view to show the com Note that each post has its own individual comments collection, accessible as +@post.comments+. That's a consequence of the declarative associations in the models. Path helpers such as +post_comments_path+ come from the nested route declaration in +config/routes.rb+. +h4. Deleting Associated Objects + +If you decide at some point to delete a post, you likely want to delete the comments associated with that post as well. You can do so by taking advantage of the association option +dependent+. All you need to do is modify the +post.rb+ as follows: + +<ruby> +class Post < ActiveRecord::Base + validates_presence_of :name, :title + validates_length_of :title, :minimum => 5 + has_many :comments, :dependent => :destroy + has_many :tags + + accepts_nested_attributes_for :tags, :allow_destroy => :true, + :reject_if => proc { |attrs| attrs.all? { |k, v| v.blank? } } +end +</ruby> + h3. Building a Multi-Model Form Comments and posts are edited on two separate forms - which makes sense, given the flow of this mini-application. But what if you want to edit more than one thing on a single form? Rails 2.3 offers new support for nested forms. Let's add support for giving each post multiple tags, right in the form where you create the post. First, create a new model to hold the tags: @@ -1221,7 +1234,7 @@ class Post < ActiveRecord::Base has_many :comments has_many :tags - accepts_nested_attributes_for :tags, :allow_destroy => :true , + accepts_nested_attributes_for :tags, :allow_destroy => :true, :reject_if => proc { |attrs| attrs.all? { |k, v| v.blank? } } end </ruby> @@ -1240,7 +1253,7 @@ You'll also need to modify +views/posts/_form.html.erb+ to include the tags: <%= post_form.text_field :name %> </p> <p> - <%= post_form.label :title, "title" %><br /> + <%= post_form.label :title, "Title" %><br /> <%= post_form.text_field :title %> </p> <p> @@ -1278,6 +1291,7 @@ Now that you've seen your first Rails application, you should feel free to updat * The "Ruby On Rails guides":http://guides.rubyonrails.org * The "Ruby on Rails mailing list":http://groups.google.com/group/rubyonrails-talk * The #rubyonrails channel on irc.freenode.net +* The "Rails Wiki":http://wiki.rubyonrails.org/ Rails also comes with built-in help that you can generate using the rake command-line utility: |