Assets are located in any arbitrary folder—
Flutter has no predefined folder structure.
You declare the assets (with location) in
the pubspec.yaml file, and Flutter picks them up.

For example, to add an image called my_icon.png to your Flutter
project, you might decide to store it in a folder arbitrarily called images.
Place the base image (1.0x) in the images folder, and the
other variants in sub-folders named after the appropriate ratio multiplier:

Next, declare these images in the pubspec.yaml file:

assets

images/my_icon.png

You can now access your images using AssetImage:

or directly in an Image widget:

For more details, see
Adding Assets and Images in Flutter.

Form input

This section discusses how to use forms in Flutter
and how they compare with UIKit.

Retrieving user input