The Flask Mega-Tutorial, Part XII: Facelift
The goal of the tutorial series is to develop a decently featured microblogging application that demonstrating total lack of originality I have decided to call
Here is an index of all the articles in the series that have been published to date:
- Part I: Hello, World!
- Part II: Templates
- Part III: Web Forms
- Part IV: Database
- Part V: User Logins
- Part VI: Profile Page And Avatars
- Part VII: Unit Testing
- Part VIII: Followers, Contacts And Friends
- Part IX: Pagination
- Part X: Full Text Search
- Part XI: Email Support
- Part XII: Facelift (this article)
- Part XIII: Dates and Times
- Part XIV: I18n and L10n
- Part XV: Ajax
- Part XVI: Debugging, Testing and Profiling
- Part XVII: Deployment on Linux (even on the Raspberry Pi!)
- Part XVIII: Deployment on the Heroku Cloud
If you have been playing with the
microblog application you must have noticed that we haven't spent too much time on its looks. Up to now the templates we put together were pretty basic, with absolutely no styling. This was useful, because we did not want the distraction of having to write good looking HTML when we were coding.
But we've been hard at work coding for a while now, so today we are taking a break and will see what we can do to make our application look a bit more appealing to our users.
This article is going to be different than previous ones because writing good looking HTML/CSS is a vast topic that falls outside of the intended scope of this series. There won't be any detailed HTML or CSS, we will just discuss basic guidelines and ideas so on how to approach the task.
How do we do this?
While we can argue that coding is hard, our pains are nothing compared to those of web designers, who have to write templates that have a nice and consistent look on a list of web browsers, most with obscure bugs or quirks. And in this modern age they not only need to make their designs look good on regular browsers but also on the resource limited browsers of tablets and smartphones.
So how can we approach the task of styling
microblog with these constraints?
Our good friends at Twitter have released an open source web framework called Bootstrap that might be our winning ticket.
These are some of the things Bootstrap is good at:
- Similar looks in all major web browsers
- Handling of desktop, tablet and phone screen sizes
- Customizable layouts
- Fully styled navigation bars
- Fully styled forms
- And much, much more...
In Flask applications the
app/static folder is where regular files go. The web server knows to go look for files in these location when a URL has a
For example, if we store a file named
/app/static then in an HTML template we can display the image with the following tag:
<img src="/static/image.png" />
We will install the Bootstrap framework according to the following structure:
/app /static /css bootstrap.min.css bootstrap-responsive.min.css /img glyphicons-halflings.png glyphicons-halflings-white.png /js bootstrap.min.js
Then in the
head section of our base template we load the framework according to the instructions:
<!DOCTYPE html> <html lang="en"> <head> ... <link href="/static/css/bootstrap.min.css" rel="stylesheet" media="screen"> <link href="/static/css/bootstrap-responsive.css" rel="stylesheet"> <script src="http://code.jquery.com/jquery-latest.js"></script> <script src="/static/js/bootstrap.min.js"></script> <meta name="viewport" content="width=device-width, initial-scale=1.0"> ... </head> ... </html>
meta tag enables Bootstrap's responsive mode, which scales the page appropriately for desktops, tablets and smartphones.
With these changes incorporated into our
base.html template we are ready to start implementing Bootstrap, which simply involves changing the HTML in our templates.
The changes that we will make are:
- Enclose the entire page contents in a single column fixed layout with responsive features.
- Adapt all forms to use Bootstrap form styles.
- Replace our navigation bar with a Navbar.
- Convert the previous and next pagination links to Pager buttons.
- Use the Boostrap alert styles for flashed messages.
- Use styled images to represent the suggested OpenID providers in the login form.
We will not discuss the specific changes to achieve the above since these are pretty simple. For those interested, the actual changes can be viewed in diff form on this github commit. The Bootstrap reference documentation will be useful when trying to analyze the new
Today we've made the promise to not write a single line of code, and we stuck to it. All the improvements we've made were done with edits to the template files.
To give you an idea of the magnitude of the transformation, here are a few before and after screenshots. Click on the images to enlarge.
The updated application can be downloaded below:
In the next chapter we will look at improving the formatting of dates and times in our application. I look forward to see you then!