Check out example codes for "flutter app icon". It will help you in understanding the concepts better.

Code Example 1

dependencies:
  flutter_launcher_icons: ^0.7.5

Code Example 2

dev_dependencies:
  flutter_launcher_icons: "^0.7.3"

flutter_icons:
  android: "launcher_icon"
  ios: true
  image_path: "assets/icon/icon.png"

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