[Unity] Basic introduction to Canvas and UI screen adaptation

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1. Basic introduction

1. What is Canvas?

When using the Unity engine to develop games, you can use Canvas (canvas) to handle the user interface (UI) in the game.

Canvas is the most basic container control of UGUI system. All UI controls must be located within the Canvas control, that is, they must be sub-controls of the Canvas container. The main function of Canvas is to provide a container to place and manage UI elements. You can control the position, level, and rendering method of UI elements by setting the properties of Canvas.