42 Flutter: Using Image Assets

main.dart

import 'package:flutter/material.dart';
import 'package:tutorial/widgets.dart';

void main() {
  runApp(new MyApp());
}

class MyApp extends StatelessWidget{
  @override
  Widget build(BuildContext context) {

    return new MaterialApp(
      title: 'Flutter Demo',
      home: new Texty(),
    );
  }

}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage>{
  @override
  Widget build(BuildContext context) {

    return new Scaffold(
      appBar: new AppBar(
        title: new Text('Flutter Demo'),
      ),
      body: new Center(
        child: new MyExploreWidget(),
      ),
    );

  }
}

widgets.dart

import 'package:flutter/material.dart';

class Texty extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new Container(child: new Text('This works'));
  }
}

class MyExploreWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    var assetsImage = new AssetImage('assets/explore.png');
    var image = new Image(image: assetsImage, width: 48.0, height: 48.0);
    return new Container(child: image);
  }
}

We've created assets directory in our Flutter app to store all our images used in this project and defined that in pubspec.yaml file

pubspec.yaml

name: tutorial
description: A new Flutter project.

dependencies:
  flutter:
    sdk: flutter
  path_provider: "^0.4.0"

  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^0.1.0

dev_dependencies:
  flutter_test:
    sdk: flutter


# For information on the generic Dart part of this file, see the
# following page: https://www.dartlang.org/tools/pub/pubspec

# The following section is specific to Flutter.
flutter:

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.
  uses-material-design: true

  # To add assets to your application, add an assets section, like this:
   assets:
    - assets/explore.png
    - assets/2.0x/explore.png

  # An image asset can refer to one or more resolution-specific "variants", see
  # https://flutter.io/assets-and-images/#resolution-aware.

  # For details regarding adding assets from package dependencies, see
  # https://flutter.io/assets-and-images/#from-packages

  # To add custom fonts to your application, add a fonts section here,
  # in this "flutter" section. Each entry in this list should have a
  # "family" key with the font family name, and a "fonts" key with a
  # list giving the asset and other descriptors for the font. For
  # example:
  # fonts:
  #   - family: Schyler
  #     fonts:
  #       - asset: fonts/Schyler-Regular.ttf
  #       - asset: fonts/Schyler-Italic.ttf
  #         style: italic
  #   - family: Trajan Pro
  #     fonts:
  #       - asset: fonts/TrajanPro.ttf
  #       - asset: fonts/TrajanPro_Bold.ttf
  #         weight: 700
  #
  # For details regarding fonts from package dependencies, 
  # see https://flutter.io/custom-fonts/#from-packages