In the first uniapp project created, the appvue file belongs to the entry file of the project, and the appvue file plays the role of a framework for carrying applications in the uniapp project, including the global configuration of applications, life cycle functions and other important contents. Appvue file is the root component of uniapp project, which is responsible for rendering other components and pages, introducing other components for internal use, configuring global styles and variables of applications, and handling life cycle events of applications.