In this PHP tutorial, we'll introduce Traits in PHP and how you can utilize them to reuse your code.
In modern PHP, you're going to spend a lot of time working with other people's classes: via external libraries that you bring into your project to get things done faster. Of course, when you do that: you can't actually edit their code if you need to change or add some behavior.
Fortunately, object-oriented code gives us some really neat ways to deal with this limitation. In this tutorial, you'll learn a method called composition in which we'll create a wrapper class, which has some subtle advantages over using inheritance.
Additional resources
Object-Oriented PHP (Topic) (Drupalize.Me)
List of contributors involved in project management and guide-wide writing/editing tasks.
Overview of regions from a theming perspective.
How to edit basic site information (site name, slogan, and default time zone).
How to install a core or contributed module, using the administrative interface or Drush.
Overview of administrative menu and contextual links.
How to edit a theme’s settings to update the color scheme and add a logo.
How to change user account registration settings.
How to create a content item for use as the home page.
How to edit content with the in-place editor.
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How to synchronize the configuration between a development and live site using the core Configuration Manager module.
How to copy a view created in a local development site to a production site.