Hmmm, ok well I followed all the steps (only creating the styles.css sheet/copy) and pasted the info at the very top, but all this seems to do when activated is revert back to the original theme of WP.
I guess, First you copied style.css from showcase folder and pasted it here on this path: wp-content/themes/showcase-child/style.css and then you copy/pasted that example code in style.css on above mentioned path. isn’t it?
Remove each and everything from style.css on this path: wp-content/themes/showcase-child/style.css. Means, you should have an empty style.css file there.
Then paste the following code in it.
Theme Name: Showcase Child
Theme URI: http: //mr49online.wordpress.com/
Description: Child theme for the Showcase theme
Author: Muhammad Farhan
Author URI: http: //mr49online.wordpress.com/about/
*/ @import url(“../showcase/style.css”);`
Now activate this Showcase Child theme
Add any style you want under @import url(….) statement.