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<title>Learning TurboGears 2.0: Quick guide to the Quickstart pages.</title>
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${sidebar_top()}
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<div id="getting_started">
<h2>Architectural basics of a quickstart TG2 site.</h2>
<p>The TG2 quickstart command produces this basic TG site. Here's how it works.</p>
<ol id="getting_started_steps">
<li class="getting_started">
<h3>Code my data model</h3>
<p> When you want a model for storing favorite links or wiki content,
the <strong>/model</strong> folder in your site is ready to go.</p>
<p> You can build a dynamic site without any data model at all. There
still be a default data-model template for you if you didn't enable
authentication and authorization in quickstart. If you have enabled
authorization, the auth data-model is ready-made.</p>
</li>
<li class="getting_started">
<h3>Design my URL structure</h3>
<p> The "<span class="code">root.py</span>" file under the
<strong>/controllers</strong> folder has your URLs. When you
called this url (<span class="code"><a href="${tg.url('/about')}">about</a></span>),
the command went through the RootController class to the
<span class="code">about</span><span class="code">()</span> method.</p>
<p> Those Python methods are responsible to create the dictionary of
variables that will be used in your web views (template).</p>
</li>
<li class="getting_started">
<h3>Reuse the web page elements</h3>
<p> A web page viewed by user could be constructed by single or
several reusable templates under <strong>/templates</strong>.
Take 'about' page for example, each reusable templates generating
a part of the page. We'll cover them in the order of where they are
found, listed near the top of the about.html template</p>
<p> <strong><span class="code">header.html</span></strong> - The
"header.html" template contains the HTML code to display the
'header': The blue gradient, TG2 logo, and some site text at the
top of every page it is included on. When the "about.html" template
is called, it includes this "header.html" template (and the others)
with a <span class="code"><xi:include /></span> tag, part of
the Genshi templating system. The "header.html" template is not a
completely static HTML -- it also dynamically displays the current
page name with a Genshi template method called "replace" with the
code: <span class="code"><span py:replace="page"/></span>.
It means replace this <span class="code"><span /></span>
region with the contents found in the variable 'page' that has
been sent in the dictionary to this "about.html" template, and is
available through that namespace for use by this "header.html"
template. That's how it changes in the header depending on what
page you are visiting.
</p>
<p> <strong><span class="code">sidebars.html</span></strong> - The
sidebars (navigation areas on the right side of the page) are
generated as two separate <span class="code">py:def</span> blocks
in the "sidebars.html" template. The <span class="code">py:def</span>
construct is best thought of as a "macro" code... a simple way to
separate and reuse common code snippets. All it takes to include
these on the "about.html" page template is to write
<span class="code">
<br/><br/>
$${sidebar_top()}
<br/>
$${sidebar_bottom()}
<br/><br/>
</span> in the page where they are wanted. CSS styling (in
"/public/nf/css/style.css") floats them off to the right side. You can
remove a sidebar or add more of them, and the CSS will place them one
atop the other.</p>
<p>This is, of course, also exactly how the header and footer
templates are also displayed in their proper places, but we'll
cover that in the "master.html" template below.</p>
<p>Oh, and in sidebar_top we've added a dynamic menu that shows the
link to this page at the top when you're at the "index" page, and
shows a link to the Home (index) page when you're here. Study the
"sidebars.html" template to see how we used
<span class="code">py:choose</span> for that.</p>
<p> <strong><span class="code">footer.html</span></strong> - The
"footer.html" block is simple, but also utilizes a special
"replace" method to set the current YEAR in the footer copyright
message. The code is:
<span class="code"><span py:replace="now.strftime('%Y')">
</span> and it uses the variable "now" that was passed
in with the dictionary of variables. But because "now" is a
datetime object, we can use the Python
<span class="code">"strftime()"</span> method with the "replace"
call to say "Just Display The Year Here". Simple, elegant; we
format the date display in the template (the View in the
Model/View/Controller architecture) rather than formatting it in
the Controller method and sending it to the template as a string
variable.</p>
<p> <strong><span class="code">master.html</span></strong> - The
"master.html" template is called last, by design. The "master.html"
template controls the overall design of the page we're looking at,
calling first the "header" py:def macro, then the putting everything
from this "about.html" template into the "main_content" div, and
then calling the "footer" macro at the end. Thus the "master.html"
template provides the overall architecture for each page in this
site.</p>
<p>But why then shouldn't we call it first? Isn't it the most
important? Perhaps, but that's precisely why we call it LAST.
The "master.html" template needs to know where to find everything
else, everything that it will use in py:def macros to build the
page. So that means we call the other templates first, and then
call "master.html". </p>
<p>There's more to the "master.html" template... study it to see how
the <title> tags and static JS and CSS files are brought into
the page. Templating with Genshi is a powerful tool and we've only
scratched the surface. There are also a few little CSS tricks
hidden in these pages, like the use of a "clearingdiv" to make
sure that your footer stays below the sidebars and always looks
right. That's not TG2 at work, just CSS. You'll need all your
skills to build a fine web app, but TG2 will make the hard parts
easier so that you can concentrate more on good design and content
rather than struggling with mechanics.</p>
</li>
</ol>
<p>Good luck with TurboGears 2!</p>
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