Storing style sheet data in user settings
While most common plugin options are typically presented to users as simple textboxes, checkboxes, or drop-down lists, there are instances where more text needs to be stored for user settings. A good example of this is plugin-specific style sheets, which can allow users to change the visual appearance of plugin output. While loading a separate style sheet file worked well in the Loading a style sheet to format plugin output recipe in Chapter 2, Plugin Framework Basics, this approach did not give users any liberty in changing these styling rules to work better with their site design, since any changes that users make to the stylesheet will get overwritten when the plugin is updated using the WordPress plugin upgrade process.
One solution to this problem is to store style sheet data with the rest of the configuration options in the site database. This way, the information will remain intact when upgrades are performed. This recipe shows how...