Archives for March 2012

March 29, 2012

Things To Fix After Each Kernel Update

Every now and then, your running Linux distro will receive a kernel update. It’s a normal part of running a Linux distro, or any OS for that matter. Mac OS and Windows perform updates as well. Unfortunately in Linux, there are certain things that break after each kernel update. It’s annoying as all get out, but its a small price to pay for running a secure desktop. In this article, I will list 3 things that need fixing, and their solutions, after each kernel update.

Fix Virtualbox

sudo /etc/init.d/vboxdrv setup

Fix Alsa

sudo apt-get install module-assistant
sudo m-a update
sudo m-a prepare
sudo m-a a-i alsa

Fix Webcam

sudo rmmod uvcvideo
sudo modprobe uvcvideo

I rather not to do this after each upgrade, but it’s a fact of life in the Linux world. It’s a good thing, it doesn’t happen very often. Perhaps, in the future, when Linux becomes perfect, or near perfect, this unnecessary exercise can all be avoided all together.

March 22, 2012

JQuery Datepicker

Typing in dates in a date field is never fun. It’s cumbersome. There is always a possibility of typing in the wrong format. There are far superior techniques that can be used and implemented when populating date fields.

JQuery is one tool that can be used to format date fields. JQuery is a set Javascript libraries that simplifies HTML document traversing, event handling, animating, and Ajax interactions for rapid web development.

JQuery has a component called JQuery UI, that provides low-level interaction like animation, advanced effects and themeable widgets use to build highly interactive web applications.

1. Download JQuery UI.

You can build your own custom JQuery scripts directly from JQuery’s website. You can select which feature you want installed. You can also select a specific theme. By selecting only the theme and features that you want, you can create a lean, strip-down version of JQuery. The download will include the following folders: css, js, development-bundle.

2. A Sample Datepicker Page

I created a simple HTML page that display how Datepicker works. In this example, I’m referencing Jquery UI from a local file. You can use a CDN if you want. I’m using the Smoothness theme and its supplied CSS.

The HTML input form needs to have an ID. In this case, we are using the id=”datepicker” for the date field. We are forcing the datepicker to use the ISO 8601 format which is “yy-mm-dd.”

<link href="css/smoothness/jquery-ui-1.8.18.custom.css" rel="Stylesheet" type="text/css" />
<script type="text/javascript" src="js/jquery-1.7.1.min.js"></script>
<script type="text/javascript" src="js/jquery-ui-1.8.18.custom.min.js"></script>
<script type="text/javascript">
// <![CDATA[
  $(function() {
  $( "#datepicker" ).datepicker({dateFormat: 'yy-mm-dd'});
  });
// ]]>
</script>

Here’s a demo.

March 9, 2012

Raspberry Pi

Watch out Apple, there’s another fruit in the market. Yesterday, I was ogling Apple’s TV which sells for just $99. That has to be one of the most affordable hardware sold by Apple. Except for the iPod shuffle, which sells for a mere $49. Which brings me to my main topic today, the Raspberry Pi, a full-fledged computer being sold for just $35. Did I hear that right?

The Raspberry Pi is powered by an Arm-based processor. It’s about the size of a credit card. It comes with a HDMI port, 2 USB ports for connecting keyboard and mouse, an audio output, a composite output for old-style TVs and monitors, an Ethernet port for the network, and a SD card slot for loading the operating system. It runs on just 2 watts of power, and it boots in less than 15 seconds.

The best part of it all, it runs on Linux, an open-source operating system. Since it’s open-source, you can do practically anything to it. Currently, there are 3 Linux distro images available for the Raspberry Pi. They are: Debian squeeze, Arch Linux ARM, and Fedora 14 Remix. There are many potential uses for the Raspberry Pi, such as a media center, cafe internet workstations, robotics, to name a few.

Finally, here’s a video of the Raspberry Pi. Yea, I want one or two.