Initial implementation

analysis_options.yaml

@@ -0,0 +1,3 @@
+analyzer:
+#  enable-experiment:
+#    - non-nullable

example/android/app/build.gradle

@@ -33,7 +33,7 @@ android {
 
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
-        applicationId "bratan.me.example"
+        applicationId "leadcode.io.example"
         minSdkVersion 16
         targetSdkVersion 28
         versionCode flutterVersionCode.toInteger()

example/android/app/src/debug/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="bratan.me.example">
+    package="leadcode.io.example">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->

example/android/app/src/main/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="bratan.me.example">
+    package="leadcode.io.example">
 
     <!-- io.flutter.app.FlutterApplication is an android.app.Application that
          calls FlutterMain.startInitialization(this); in its onCreate method.

example/android/app/src/main/java/bratan/me/example/MainActivity.java

@@ -1,4 +1,4 @@
-package bratan.me.example;
+package leadcode.io.example;
 
 import android.os.Bundle;
 import io.flutter.app.FlutterActivity;

example/android/app/src/profile/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="bratan.me.example">
+    package="leadcode.io.example">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->

example/ios/Runner.xcodeproj/project.pbxproj

@@ -324,7 +324,7 @@
 					"$(inherited)",
 					"$(PROJECT_DIR)/Flutter",
 				);
-				PRODUCT_BUNDLE_IDENTIFIER = bratan.me.example;
+				PRODUCT_BUNDLE_IDENTIFIER = leadcode.io.example;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
@@ -453,7 +453,7 @@
 					"$(inherited)",
 					"$(PROJECT_DIR)/Flutter",
 				);
-				PRODUCT_BUNDLE_IDENTIFIER = bratan.me.example;
+				PRODUCT_BUNDLE_IDENTIFIER = leadcode.io.example;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
@@ -476,7 +476,7 @@
 					"$(inherited)",
 					"$(PROJECT_DIR)/Flutter",
 				);
-				PRODUCT_BUNDLE_IDENTIFIER = bratan.me.example;
+				PRODUCT_BUNDLE_IDENTIFIER = leadcode.io.example;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				VERSIONING_SYSTEM = "apple-generic";
 			};

example/pubspec.yaml

@@ -1,4 +1,4 @@
-name: flutter_translate_example
+name: example
 description: Example project for the flutter_translate library
 
 # The following defines the version and build number for your application.
@@ -29,3 +29,5 @@ dev_dependencies:
 flutter:
 
   uses-material-design: true
+  assets:
+    - assets/i18n/

lib/flutter_translate.dart

@@ -1,3 +1,8 @@
 library flutter_translate;
 
 export 'package:flutter_translate/localization.dart';
+export 'package:flutter_translate/localization_configuration.dart';
+export 'package:flutter_translate/localization_delegate.dart';
+export 'package:flutter_translate/localization_provider.dart';
+export 'package:flutter_translate/localized_app.dart';
+export 'package:flutter_translate/localized_app_state.dart';

lib/helpers.dart

@@ -0,0 +1,17 @@
+import 'dart:ui';
+
+Locale localeFromString(String code, {bool languageCodeOnly})
+{
+    if(code.contains('_'))
+    {
+        var parts = code.split('_');
+
+        return languageCodeOnly ? Locale(parts[0]) : Locale(parts[0], parts[1]);
+    }
+    else
+    {
+        return Locale(code);
+    }
+}
+
+

lib/localization.dart

@@ -1,8 +1,45 @@
-import 'package:flutter/widgets.dart';
+import 'package:flutter/cupertino.dart';
 
 class Localization
 {
-    Locale locale;
+    final Map<String, dynamic> translations;
+
+    Localization(this.translations);
 
     static Localization of(BuildContext context) => Localizations.of<Localization>(context, Localization);
+
+    String key(String key, {List<String> args})
+    {
+        var value = _getValue(key, translations);
+
+        if (args != null)
+        {
+            args.forEach((String str)
+            {
+                value = value.replaceFirst(RegExp(r'{}'), str);
+            });
+        }
+
+        return value;
+    }
+
+    String _getValue(String path, Map<String, dynamic> map)
+    {
+        List<String> keys = path.split('.');
+
+        if (keys.length > 1)
+        {
+            for (int index = 0; index <= keys.length; index++)
+            {
+                if (map.containsKey(keys[index]) && map[keys[index]] is! String)
+                {
+                    return _getValue(keys.sublist(index + 1, keys.length).join('.'), map[keys[index]]);
+                }
+
+                return map[path] ?? path;
+            }
+        }
+
+        return map[path] ?? path;
+    }
 }

lib/localization_configuration.dart

@@ -0,0 +1,60 @@
+import 'package:flutter/widgets.dart';
+import 'helpers.dart';
+import 'localization_file_service.dart';
+
+class LocalizationConfiguration
+{
+    Map<Locale, String> _localizations;
+
+    Map<Locale, String> get localizations => _localizations;
+
+    final Locale fallbackLocale;
+
+    final List<Locale> supportedLocales;
+
+    LocalizationConfiguration._(this.fallbackLocale, this.supportedLocales);
+
+    static Future<LocalizationConfiguration> create({@required String fallbackLanguage, @required List<String> supportedLanguages, @required String basePath}) async
+    {
+        var configuration = new LocalizationConfiguration._(localeFromString(fallbackLanguage), _generateSupportedLocales(supportedLanguages));
+
+        _validateConfiguration(fallbackLanguage, supportedLanguages);
+
+        var files = await LocalizationFileService.getLocalizedFiles(supportedLanguages, basePath);
+
+        configuration._localizations = files.map((x,y) => _getLocalizedEntry(x, y));
+
+       return configuration;
+    }
+
+    static void _validateConfiguration(String fallbackLanguage, List<String> supportedLanguages)
+    {
+        if(!supportedLanguages.contains(fallbackLanguage))
+        {
+            throw new Exception('The fallbackLanguage [$fallbackLanguage] must be present in the supportedLanguages list [${supportedLanguages.join(", ")}].');
+        }
+    }
+
+    static List<Locale> _generateSupportedLocales(List<String> supportedLanguages)
+    {
+        return supportedLanguages.map((x) => localeFromString(x, languageCodeOnly: true)).toSet().toList();
+    }
+
+    static MapEntry<Locale, String> _getLocalizedEntry(String languageCode, String file)
+    {
+        Locale locale;
+
+        if(languageCode.contains('_'))
+        {
+            var parts = languageCode.split('_');
+
+            locale = new Locale(parts[0], parts[1]);
+        }
+        else
+        {
+            locale = new Locale(languageCode);
+        }
+
+        return MapEntry(locale, file);
+    }
+}

lib/localization_delegate.dart

@@ -0,0 +1,50 @@
+import 'dart:convert';
+import 'package:flutter/cupertino.dart';
+import 'localization_file_service.dart';
+import 'localization_configuration.dart';
+import 'localization.dart';
+
+class LocalizationDelegate extends LocalizationsDelegate<Localization>
+{
+    final LocalizationConfiguration configuration;
+
+    LocalizationDelegate(this.configuration);
+
+    @override
+    Future<Localization> load(Locale newLocale) async
+    {
+        var locale = _findLocale(newLocale) ?? configuration.fallbackLocale;
+
+        var localizedContent = await _getLocalizedContent(locale);
+
+        return new Localization(localizedContent);
+    }
+
+    Future<Map<String, dynamic>> _getLocalizedContent(Locale locale) async
+    {
+        var file = configuration.localizations[locale];
+
+        var content = await LocalizationFileService.getLocalizedContent(file);
+
+        return json.decode(content);
+    }
+
+
+    Locale _findLocale(Locale locale)
+    {
+        var existing = configuration.localizations.keys.firstWhere((x) => x == locale, orElse: () => null);
+
+        if(existing == null)
+        {
+            existing = configuration.localizations.keys.firstWhere((x) => x.languageCode == locale.languageCode, orElse: () => null);
+        }
+
+        return existing;
+    }
+
+    @override
+    bool isSupported(Locale locale) => locale != null;
+
+    @override
+    bool shouldReload(LocalizationsDelegate<Localization> old) => true;
+}

lib/localization_file_service.dart

@@ -0,0 +1,62 @@
+import 'dart:convert';
+import 'package:flutter/services.dart';
+
+class LocalizationFileService
+{
+    static const String assetManifestFilename = 'AssetManifest.json';
+
+    static Future<Map<String, String>> getLocalizedFiles(List<String> languages, String basePath) async
+    {
+        var localizedFiles = await _getAllLocalizedFiles(basePath);
+
+        final files = new Map<String, String>();
+
+        for(final language in languages.toSet())
+        {
+            var file = _findLocalizationFile(language, localizedFiles, basePath);
+
+            files[language] = file;
+        }
+
+        return files;
+    }
+
+    static Future<String> getLocalizedContent(String file) async
+    {
+        return await rootBundle.loadString(file);
+    }
+
+    static Future<List<String>> _getAllLocalizedFiles(String basePath) async
+    {
+        final manifest = await rootBundle.loadString(assetManifestFilename);
+
+        Map<String, dynamic> map = jsonDecode(manifest);
+
+        return map.keys.where((x) => x.startsWith('$basePath/')).toList();
+    }
+
+    static String _findLocalizationFile(String languageCode, List<String> localizedFiles, String basePath)
+    {
+        var file = _getFilepath(languageCode, basePath);
+
+        if(!localizedFiles.contains(file))
+        {
+            if(languageCode.contains('_'))
+            {
+                file = _getFilepath(languageCode.split('_').first, basePath);
+            }
+        }
+
+        if(file == null)
+        {
+            throw new Exception('The asset file for the language "$languageCode" was not found.');
+        }
+
+        return file;
+    }
+
+    static String _getFilepath(String languageCode, String basePath)
+    {
+        return '$basePath/$languageCode.json';
+    }
+}

lib/localization_provider.dart

@@ -0,0 +1,16 @@
+import 'package:flutter/widgets.dart';
+import 'localized_app_state.dart';
+
+class LocalizationProvider extends InheritedWidget
+{
+    final LocalizedAppState state;
+
+    final Widget child;
+
+    LocalizationProvider({Key key, this.child, this.state}) : super(key: key, child: child);
+
+    static LocalizationProvider of(BuildContext context) => (context.inheritFromWidgetOfExactType(LocalizationProvider) as LocalizationProvider);
+
+    @override
+    bool updateShouldNotify(LocalizationProvider oldWidget) => true;
+}

lib/localized_app.dart

@@ -0,0 +1,11 @@
+import 'package:flutter/widgets.dart';
+import 'localized_app_state.dart';
+
+class LocalizedApp extends StatefulWidget
+{
+    final Widget child;
+
+    LocalizedApp(this.child);
+
+    LocalizedAppState createState() => LocalizedAppState();
+}

lib/localized_app_state.dart

@@ -0,0 +1,18 @@
+import 'package:flutter/widgets.dart';
+import 'localized_app.dart';
+import 'localization_provider.dart';
+
+class LocalizedAppState extends State<LocalizedApp>
+{
+    Locale _currentLocale;
+
+    Locale get currentLocale => _currentLocale;
+
+    void changeLanguage(Locale newLocale)
+    {
+        setState(() => _currentLocale = newLocale);
+    }
+
+    @override
+    Widget build(BuildContext context) => LocalizationProvider(state: this, child: widget.child);
+}

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flutter_translate
 description: The internationalization (i18n) library for Flutter.
-version: 0.0.2
+version: 1.0.0
 author: Leadcode <dev@leadcode.io>
 homepage: https://github.com/leadcode/flutter_translate
 
@@ -10,6 +10,8 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
+  flutter_localizations:
+    sdk: flutter
 
 dev_dependencies: