How do you add assets and images to a Flutter app?

Short answer

You declare the paths in pubspec.yaml and then use the appropriate APIs to load them, and the paths and indentation must be correct within the asset bundle.

Explanation

Flutter does not include a file just because it exists in the repository; pubspec determines what goes into the asset bundle. Declare a folder or file clearly, use the package prefix when consuming an asset from another package, and then test the final build, not only hot reload.

Common mistakes

• Forgetting to declare an asset or an indentation error in YAML.
• Using a local path that works in debug but does not exist inside the published bundle.

Follow-up questions

• What is the role of pubspec.yaml and pubspec.lock in a Flutter project?

Sources

• Flutter docs — Assets and images