以 package 的方式使用字体
自定义字体,除了可以把字体文件作为应用的一部分之外,还可以通过 package 的方式使用,这样有助于跨项目的字体共享,也可以更方便的发布到 pub.dev。
Rather than declaring a font as part of an app, you can declare a font as part of a separate package. This is a convenient way to share the same font across several different projects, or for coders publishing their packages to pub.dev. This recipe uses the following steps:
步骤
Directions
-
将字体添加到 package
Add a font to a package.
-
将 package 和字体添加到应用
Add the package and font to the app.
-
使用字体
Use the font.
1. 将字体添加到 package
1. Add a font to a package
通过 package 的方式使用字体,需要将字体文件导入 package 项目的 lib
文件夹中。你既可以将字体文件直接放在 lib
文件夹中,也可以放在子目录中,例如 lib/fonts
。
To export a font from a package, you need to import the font files into the
lib
folder of the package project. You can place font files directly in the
lib
folder or in a subdirectory, such as lib/fonts
.
在此示例中,假设你已有一个名为 awesome_package
的 library,其中包含了 lib/fonts
文件夹中的字体资源。
In this example, assume you’ve got a Flutter library called
awesome_package
with fonts living in a lib/fonts
folder.
awesome_package/
lib/
awesome_package.dart
fonts/
Raleway-Regular.ttf
Raleway-Italic.ttf
2. 将 package 和字体添加到应用
2. Add the package and fonts to the app
现在你可以使用该 package 以及它提供的字体。我们来编辑 应用程序 根目录下的 pubspec.yaml
文件。
Now you can use the fonts in the package by
updating the pubspec.yaml
in the app’s root directory.
将 package 添加到应用中
Add the package to the app
dependencies:
awesome_package: <latest_version>
声明字体资源
Declare the font assets
现在已经导入了 package,你需要告之 Flutter
在 awesome_package
中的哪里可以找到字体文件。
Now that you’ve imported the package, tell Flutter where to
find the fonts from the awesome_package
.
要想声明 package 中的字体,必须在 packages/awesome_package
的路径前加上字体声明。这将会让 Flutter 检索到 lib
package 的文件夹中的字体。
To declare package fonts, prefix the path to the font with
packages/awesome_package
.
This tells Flutter to look in the lib
folder
of the package for the font.
flutter:
fonts:
- family: Raleway
fonts:
- asset: packages/awesome_package/fonts/Raleway-Regular.ttf
- asset: packages/awesome_package/fonts/Raleway-Italic.ttf
style: italic
3. 使用字体
3. Use the font
你可以使用 TextStyle
来更改文本的外观。在使用 package 中的字体时,你不仅需要声明该文字所要使用的字体,还需要声明字体所属的 package
。
Use a TextStyle
to change the appearance of text.
To use package fonts, declare which font you’d like to use and
which package the font belongs to.
Text(
'Using the Raleway font from the awesome_package',
style: TextStyle(
fontFamily: 'Raleway',
package: 'awesome_package',
),
);
完整样例
Complete example
字体
Fonts
这里所使用的 Raleway 和 RobotoMono 字体都是从 Google Fonts 下载的。
The Raleway and RobotoMono fonts were downloaded from Google Fonts.
pubspec.yaml
name: package_fonts
description: An example of how to use package fonts with Flutter
dependencies:
awesome_package:
flutter:
sdk: flutter
dev_dependencies:
flutter_test:
sdk: flutter
flutter:
fonts:
- family: Raleway
fonts:
- asset: packages/awesome_package/fonts/Raleway-Regular.ttf
- asset: packages/awesome_package/fonts/Raleway-Italic.ttf
style: italic
uses-material-design: true
main.dart
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Package Fonts',
home: MyHomePage(),
);
}
}
class MyHomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
// The AppBar uses the app-default font.
appBar: AppBar(title: Text('Package Fonts')),
body: Center(
// This Text widget uses the Raleway font.
child: Text(
'Using the Raleway font from the awesome_package',
style: TextStyle(
fontFamily: 'Raleway',
package: 'awesome_package',
),
),
),
);
}
}