When I first saw this question at WordPress answers which asks for a QR Code plugin suggestion i answered that a plugin is not really needed and posted a simple function to achieve that, little did i know that just a few weeks later a client will ask me to create this very plugin for him. so after the plugin was made for that client i customized it a bit and i give you Simple QR Code
  

Screenshots:

What does it do?

This Plugin allows you add a QR Code to your posts/pages/custom using a simple shortcode and to your sidebars using a built-in widget.
  

How does it work?

This plugin works with the Google charts API to generate the encoded QR code image.
  

Features:

• Very easy to use.
• TinyMCE button for easy shortcode insertion.
• Custom sizes
• Built-in Widget.
• Use as shortcode.
• Use as template tag for easy integration with your theme or plugin.

Download:

Download the latest Version from WordPress.org

Simple Installation steps:

1. Extract the zip file and just drop the contents in the wp-content/plugins/ directory of your WordPress installation.
2. Then activate the Plugin from Plugins page.
3. Done!

Usage:

Shortcode -
Simply create or edit post/page and click the newly added TinyMCE button (the one with the barcode icon) add fill that simple form. Alternatively you can insert the shortcode yourself for example:

[QR size="240x240" link="yes"]http://en.bainternet.info[/QR]

.

Widget – Once again the widget as a simple options panel which are easy to follow.
Template Tag – if you want to use it in a template file then just use

<?php echo do_shortcode('[QR size="240x240" link="yes"]http://en.bainternet.info[/QR]'); ?> 

this is it for now, enjoy and any feedback is welcome, also make sure to submit bug if you find any.
  

Change Log:

• 1.0
  • Initial release

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