View is the base class for widgets, which are used to create interactive UI components (buttons, text fields, etc.). All of the views in a window are arranged in a single tree. You can add views either from code or by specifying a tree of views in one or more XML layout files. There are many specialized subclasses of views that act as controls or are capable of displaying text, images, or other content.
The base LayoutParams class just describes how big the view wants to be for both width and height. For each dimension, it can specify one of: