While widgets are primarily used by website administrators to easily add content to their front-facing websites, WordPress contains another type of widget that plugin developers can use to enhance user experience. Dashboard plugins are sections that appear on the front page of a website's administration area. These sections can offer any kind of functionality, from simple information displays indicating how much data is stored in a plugin to forms that allow website administrators to quickly perform configuration tasks.
This recipe shows how to add a new dashboard widget that indicates how many book reviews are stored in the system, along with links to quickly access them.
You should have already followed the Updating page title to include custom post data using plugin filters recipe from Chapter4, The Power of Custom Post Types, to have a starting point for this recipe. Alternatively, you can get the resulting code (Chapter 4/ch4-book-reviews...