Hands-On: Build a Node.js-powered Chatroom Web App (Part Four)
Part 4 – Building a Chatroom UI with BootstrapWelcome to Part 4 of the hands-on Node.js tutorial series: Build a Node.js-powered chatroom web app. In this installment, I will show you how to add a Twitter Bootstrap-styled frontend to the chatroom backend you built in Part 2 and Part 3.
What is Bootstrap?Bootstrap is a wildly popular HTML and CSS framework for building websites and web applications. It is the number one project on GitHub. Bootstrap supports responsive web design, allowing the layout of your page to adapt to the device (desktop, tablet, mobile).
link(rel='stylesheet' href='/css/style.css')Next, we want to add the Bootstrap CSS file links to the header and the appropriate meta tags for HTML5 apps in the layout.jade file. You have to add the following lines right before the line containing the style.css link.
Creating the Chat UI LayoutIt is time to develop the chat user interface layout. First, you might want to read about Bootstrap and take a look at this long tutorial. All chat engines have an area for the recently received messages and an area for a user to write and send a message. Historically, the layout was to have the editing area attached to the bottom and the messages at the top. It is not easy to fix elements on an HTML page to the bottom of the viewport without a bit of work. I will be following this sample to fix a footer to the bottom. We want to modify the index.jade file, and remove all the lines of code under the content block. First, we add the area of the page that will contain messages received. Let’s start by adding a div with the class wrap. In Jade, all you need to write is wrap to generate a <div class=”wrap”></div>. By using the indentation, we can signal to the jade templating engine that more indented elements will go within the less indented elements. Take a look at this Jade tutorial if you missed it in the other tutorials. Next, we want to add another div with the class container-fluid to add a fluid width to the page. Inside, I will create an h1 element that says “Welcome to the Node Chatroom” and a div with an id messages and a final div with the class push that we will use to push down the message editing area of the chatroom to the bottom of the viewport.
.wrap .container-fluid h1 Welcome to the Node Chatroom #messages .pushNext, we are going to develop the message editing area. We want to capture the textbox and send button within a div called footer and a div called container-fluid. The footer div will have the same indentation as the wrap div. Next, I will use the Bootstrap grid system (read about it here) to split the message editing area into two. One of the columns will take the majority of the space and will contain the textbox for writing the message, the second column will contain a block-level button for sending the message. Note how Jade lets us specify the attributes of an element using the paragraph notation. The code will look like this:
.footer .container-fluid .row .col-xs-8.col-sm-9 input(type="text" id="message-box" class="form-control input-lg" placeholder="Write a message here..." rows="3") .col-xs-4.col-sm-3 button#send-message-btn.btn.btn-primary.btn-lg.btn-block Send Message
extends layout block content .wrap .container-fluid h1 Welcome to the Node Chatroom #messages .push .footer .container-fluid .row .col-xs-8.col-sm-9 input(type="text" id="message-box" class="form-control input-lg" placeholder="Write a message here..." rows="3") .col-xs-4.col-sm-3 button#send-message-btn.btn.btn-primary.btn-lg.btn-block Send Message
Adding CSS to Force Message Editing Area to Bottom of ViewportWe want to force the message editing area to the bottom of the viewport, we will want to add a few custom CSS in the public/css/style.styl page. This file uses the Stylus CSS preprocessor but you can also paste verbatim CSS that will be recopied into the generated CSS file. First, we will want to ensure the whole page takes up 100% of the height.
html, body height: 100%Second, we want to ensure the wrap area takes up the maximum height it can but leaves a 60px margin at the bottom for our footer and message editing area.
.wrap min-height: 100% height: auto !important height: 100% margin: 0 auto -60pxThird, we want to ensure that this space for the editing area is respected and to assign it to the footer.
.push, .footer height: 60pxFinally, for stylistic reasons, let’s a subtle background color to the footer.
.footer background-color: #f5f5f5
Completed Style.styl File
html, body height: 100% .wrap min-height: 100% height: auto !important height: 100% margin: 0 auto -60px .push, .footer height: 60px .footer background-color: #f5f5f5