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请支持原文：http://tryenough.com/flutter-tts
需求
在 flutter 中指定一段文字，播放语音。
实现
1. 添加库引用
我们这里使用 Dart 的 tts 库，首先在配置文件中添加这个库的引用：
在 pubspec.yaml 文件中添加如下代码引用：
dependencies:
tts: ^1.0.2
执行命令，获取该库：
flutter packages get
请支持原文：http://tryenough.com/flutter-tts
使用时引入头文件：
import ‘package:tts/tts.dart’;
2. 创建 tts_helper 类，作为使用 tts 的帮助类
import ‘package:tts/tts.dart’;
import ‘dart:async’;
import ‘dart:io’;
/// Singleton tool class for tts
/// Use TtsHelper step:
///
/// Method : #isLanguageAvailable judge language, here language is _languageMap’s values like “en-US”,instead of the type of ‘en’ etc..
///
/// Method : #getTtsLanguage help you convert “en” to “en-US”.
///
/// Method : #setLanguage help you set Language , but “en-US” is default value
///
/// use example:
/// TtsHelper.instance.speak(“speech content”);
/// or
/// TtsHelper.instance.setLanguageAndSpeak(“speech content”, “en-US”);
/// …
class TtsHelper {
// Locale to tss language map
static final Map<String, String> _languageMap = {
‘en’: “en-US”,
‘zh’: “zh-CN”,
“ar”: “ar-SA”,
“cs”: “cs-CZ”,
“da”: “da-DK”,
“de”: “de-DE”,
“el”: “el-GR”,
“es”: “es-ES”,
“fi”: “fi-FI”,
“fr”: “fr-CA”,
“he”: “he-IL”,
“hi”: “hi-IN”,
“hu”: “hu-HU”,
“id”: “id-ID”,
“it”: “it-IT”,
“ja”: “ja-JP”,
“ko”: “ko-KR”,
“nl”: “nl-BE”,
“no”: “no-NO”,
“pl”: “pl-PL”,
“pt”: “pt-BR”,
“ro”: “ro-RO”,
“ru”: “ru-RU”,
“sk”: “sk-SK”,
“sv”: “sv-SE”,
“th”: “th-TH”,
“tr”: “tr-TR”,
‘en-US’: “en-US”,
‘zh-CN’: “zh-CN”,
“ar-SA”: “ar-SA”,
“cs-CZ”: “cs-CZ”,
“da-DK”: “da-DK”,
“de-DE”: “de-DE”,
“el-GR”: “el-GR”,
“es-ES”: “es-ES”,
“fi-FI”: “fi-FI”,
“fr-CA”: “fr-CA”,
“he-IL”: “he-IL”,
“hi-IN”: “hi-IN”,
“hu-HU”: “hu-HU”,
“id-ID”: “id-ID”,
“it-IT”: “it-IT”,
“ja-JP”: “ja-JP”,
“ko-KR”: “ko-KR”,
“nl-BE”: “nl-BE”,
“no-NO”: “no-NO”,
“pl-PL”: “pl-PL”,
“pt-BR”: “pt-BR”,
“ro-RO”: “ro-RO”,
“ru-RU”: “ru-RU”,
“sk-SK”: “sk-SK”,
“sv-SE”: “sv-SE”,
“th-TH”: “th-TH”,
“tr-TR”: “tr-TR”,
};
static final String _defaultL = “en-US”;
List<String> _languages;
static TtsHelper _instance;
static TtsHelper get instance => _getInstance();
factory TtsHelper() =>_getInstance();
static TtsHelper _getInstance() {
if (_instance == null) {
_instance = new TtsHelper._internal();
}
return _instance;
}
TtsHelper._internal() {
// Initialize
_initPlatformState();
}
_initPlatformState() async {
_languages = await Tts.getAvailableLanguages();
// If getAvailableLanguages is null, add “en-US” to _languages.
if (_languages == null) {
_languages = [_defaultL];
}
// Default set en-US language
_setLanguage(_defaultL);
}
String _getTtsLanguage(String localeStr) {
if(localeStr == null || localeStr.isEmpty ||
!_languageMap.containsKey(localeStr)) {
return _defaultL;
}
return _languageMap[localeStr];
}
// Return whether the result if set language is successful
Future<bool> _setLanguage (String lang) async {
String language = _getTtsLanguage(lang);
if (language == null || language.isEmpty) {
language = _defaultL;
}
if(Platform.isIOS && !_languages.contains(language)) {
return false;
}
final bool isSet = await Tts.setLanguage(language);
return isSet;
}
// Returns whether the supported language is supported
Future<bool> _isLanguageAvailable (String language) async {
final bool isSupport = await Tts.isLanguageAvailable(language);
return isSupport;
}
void speak (String text) async {
if (text == null || text.isEmpty) {return;}
Tts.speak(text);
}
void setLanguageAndSpeak(String text, String language) async {
String ttsL = _getTtsLanguage(language);
var setResult = await _setLanguage(ttsL);
if(setResult != null) {
var available = await _isLanguageAvailable(ttsL);
if(available != null) {
speak(text);
}
}
}
}
请支持原文：http://tryenough.com/flutter-tts
3. 添加测试页面
import ‘package:flutter_tts/tts_helper.dart’;
import ‘package:flutter/material.dart’;
class VoiceSetPage extends StatefulWidget {
VoiceSetPage({Key key, this.title}) : super(key: key);
final String title;
@override
_VoiceSetPageState createState() => _VoiceSetPageState();
}
class _VoiceSetPageState extends State<VoiceSetPage> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: Colors.blue,
title: Text(widget.title),
elevation: 5.0, // shadow the bottom of AppBar
),
body: Center(
child: ListView(
children: <Widget>[
ListTile(
title: Text(
‘test vioce’,
style: TextStyle(fontWeight: FontWeight.w500, fontSize: 20.0),
),
onTap: () {
showAlertDialog(context);
TtsHelper.instance.setLanguageAndSpeak(“ 你好我是声音播放器 ”, “zh”);
},
),
Divider(
height: 1,
)
],
),
),
);
}
}
void showAlertDialog(BuildContext context) {
NavigatorState navigator =
context.rootAncestorStateOfType(const TypeMatcher<NavigatorState>());
debugPrint(“navigator is null?” + (navigator == null).toString());
showDialog(
context: context,
builder: (_) => new AlertDialog(
title: new Text(“Dialog Title”),
content: new Text(“This is my content”),
actions: <Widget>[
new FlatButton(
child: new Text(“CANCEL”),
onPressed: () {
Navigator.of(context).pop();
},
),
new FlatButton(
child: new Text(“OK”),
onPressed: () {
Navigator.of(context).pop();
},
)
]));
}
4. 在 main 中添加测试入口
import ‘package:flutter/material.dart’;
import ‘package:flutter_tts/voice_set_page.dart’;
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: ‘Flutter Demo’,
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: ‘Flutter Demo Home Page’),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
void _incrementCounter() {
Navigator.push(context, MaterialPageRoute(builder: (context) => VoiceSetPage(title: “Setting”)));
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
‘ 点击浮动按钮跳转到语音测试页 ’,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,
tooltip: ‘ 跳转 ’,
child: Icon(Icons.add),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
}
测试可用，希望能帮助到你。
请支持原文：http://tryenough.com/flutter-tts
完成 demo 下载地址：http://tryenough.com/flutter-tts
