Basic concepts of UI framework in activity

The basic concept of UI framework in activity activity is an essential part of the application, providing a visual interface to interact with the user, and how the acitivity displays the view elements and responds to event interactions. The concept of activity-related activity:activity contains a window, The window is created by calling Policymanager.makenewwindo in the activity's attach method; View: The most basic UI component that represents a rectangular area on the screen; Decorview: Is the rootview of the View in window, setting the window Window: Represents the top-level windows, manages the display of the interface, and responds to events; each activity creates a         Phonewindow object. is the interface between activity and the entire view system WindowManager: A interface, inherited from Viewmanager. The window manager of the application process; there is a implementation windowmanagerimpl; Mainly used to manage some of the window's state, properties, view additions, deletions, updates, window order, message collection and processing. Viewroot: Interaction with the Global window manager via the Iwindowsession interface: interface control and message response; Activitythread: The main thread of the application, which creates an association with the current Activity and window ; Create a WindowManager implementation class instance, add the current Decoview to WindowManager; Two implementation process framework diagram         activity on the window's creation Association process is as follows: Related class structure: Hierarchical relationship: (this Figure Online Misappropriation ... ）

Basic concepts of UI framework in activity