Flutter framework creates the element tree which represents the rendered widget on the screen. An Element represents the use of a widget to configure a specific location in the tree . The element can change if the parent widget rebuilds and creates a new widget for this location.
Read moreWhat is a Renderobject?
RenderObjects are those particular “Objects” responsible for controlling the sizes, layouts, and logic used for painting widgets to the screen and forming the UI for the application . You can say that the actual rendering happens in RenderObjects.
Read moreWhat is a widget in Flutter?
Widgets are the central class hierarchy in the Flutter framework. A widget is an immutable description of part of a user interface . Widgets can be inflated into elements, which manage the underlying render tree. Widgets themselves have no mutable state (all their fields must be final).
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