Context: This is my first widget and I am following along with an online tutorial. I am expecting the front-end of the widget to echo some content upon checking a check-box in the back-end form, but rather I am not seeing any content displayed.
I have attempted to follow along with these two-part tutorials http://www.wpexplorer.com/create-widget-plugin-wordpress/ and http://www.wpexplorer.com/how-to-create-a-widget-plugin-for-wordpress-part-2/ .
My complete widget file is located here http://pastebin.com/nVTzxiTQ
Back-end looks like this after saving
Front-end looks like this after saving
Question: Why isn't the act of checking the check-box in the back-end UI resulting in the rendering of the string 'Checkbox is checked' on the front-end, as I expect it to?