Flutter加载本地图片躺坑记录

步骤

1.在根目录建立一个文件夹，名称建议叫images
2.在此文件夹下建立两个文件夹，一个为2.0x,一个为3.0x，分别放置2倍图和3倍图，正常的图片直接放置到images文件夹下

images.png
3.在pubspec.yaml文件中申明本地图片：

# 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:
    - images/tupian.png

这里有一个坑，先前这个assets是官方注释的，我是直接就解开了，然后把下方的图片路径写好，编译却出现如下错误：

Error on line 29, column 4 of pubspec.yaml: Expected a key while parsing a block mapping.
   assets:
   ^

pub get failed (65)

原因是assets前面有一个空格，assets需要与上面的uses-material-design对齐，把它对齐重新编译就好了。

4.在代码中调用Image.asset()方法加载本地图片展示，示例：

import 'package:flutter/material.dart';

void main() => runApp(new MyApp());

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

    return new MaterialApp(
      title: 'Welcome to Flutter',
      home: new Scaffold(
        appBar: new AppBar(
          title: new Text('Welcome to Flutter'),
        ),
        body: new Center(
          child: new Image.asset("images/tupian.png")  //路径要写全
        ),
      ),
    );
  }
}

如果是加载第三方依赖库中的图片，需要在路径后面申明包名路径:

new Image.asset("images/tupian.png", package: 'my_package')