Language change at runtime

.packages

@@ -1,4 +1,4 @@
-# Generated by pub on 2018-09-21 20:30:26.757096.
+# Generated by pub on 2018-10-29 21:46:18.459763.
 analyzer:file:///home/teo/snap/flutter/.pub-cache/hosted/pub.dartlang.org/analyzer-0.32.4/lib/
 args:file:///home/teo/snap/flutter/.pub-cache/hosted/pub.dartlang.org/args-1.5.0/lib/
 async:file:///home/teo/snap/flutter/.pub-cache/hosted/pub.dartlang.org/async-2.0.8/lib/

README.md

@@ -69,4 +69,11 @@ Where:
 From version ***0.2.0*** *flutter_i18n* manage strings that contain parameters; an example can be: "Hello, ***{user}***!"
 For a correct translation, you must use the third parameter of the *translate* method, a *Map<String, String>* where:
 - the keys are the placeholders used in the *.json* file (i.e. user)
-- the values are what you want to display
+- the values are what you want to display
+
+From version ***0.3.0*** *flutter_i18n* supports language change at runtime. To use it, you ***must*** invoke the method
+```sh
+await FlutterI18n.refresh(buildContext, languageCode, {countryCode});
+```
+
+***NOTE***: *countryCode* is optional.

example/assets/flutter_i18n/it.json

@@ -0,0 +1,10 @@
+{
+  "title": "App di test",
+  "label":{
+    "main": "Ciao {user}!"
+  },
+  "button":{
+    "clickMe": "Premi qui"
+  },
+  "toastMessage": "Hai premuto un bottone!"
+}

example/lib/main.dart

@@ -23,7 +23,20 @@ class MyApp extends StatelessWidget {
   }
 }
 
-class MyHomePage extends StatelessWidget {
+class MyHomePage extends StatefulWidget {
+  @override
+  MyHomeState createState() => new MyHomeState();
+}
+
+class MyHomeState extends State<MyHomePage> {
+  String currentLang = 'en';
+
+  switchLang() {
+    setState(() {
+      currentLang = currentLang == 'en' ? 'it' : 'en';
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
@@ -34,13 +47,16 @@ class MyHomePage extends StatelessWidget {
           child: new Column(
             mainAxisAlignment: MainAxisAlignment.center,
             children: <Widget>[
-              new Text(FlutterI18n.translate(context, "label.main",  Map.fromIterables(["user"], ["Flutter lover"]))),
+              new Text(FlutterI18n.translate(context, "label.main",
+                  Map.fromIterables(["user"], ["Flutter lover"]))),
               new FlatButton(
-                  onPressed: () {
+                  onPressed: () async {
+                    switchLang();
+                    await FlutterI18n.refresh(context, currentLang);
                     Scaffold.of(context).showSnackBar(new SnackBar(
-                          content: new Text(
-                              FlutterI18n.translate(context, "toastMessage")),
-                        ));
+                      content: new Text(
+                          FlutterI18n.translate(context, "toastMessage")),
+                    ));
                   },
                   child: new Text(
                       FlutterI18n.translate(context, "button.clickMe")))

example/pubspec.lock

@@ -82,7 +82,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.0.3"
+    version: "0.3.0"
   flutter_localizations:
     dependency: transitive
     description: flutter

lib/flutter_i18n.dart

@@ -26,8 +26,8 @@ class FlutterI18n {
     return true;
   }
 
-  Future _loadCurrentTranslation() async {
-    this.locale = await _findCurrentLocale();
+  Future _loadCurrentTranslation([final Locale locale]) async {
+    this.locale = locale != null ? locale : await _findCurrentLocale();
     await _loadFile(_composeFileName());
   }
 
@@ -52,6 +52,13 @@ class FlutterI18n {
         () => Locale(systemLocaleSplitted[0], systemLocaleSplitted[1]));
   }
 
+  static Future refresh(final BuildContext context, final String languageCode,
+      {final String countryCode}) async {
+    final Locale forcedLocale = new Locale(languageCode, countryCode);
+    final FlutterI18n currentInstance = retrieveCurrentInstance(context);
+    await currentInstance._loadCurrentTranslation(forcedLocale);
+  }
+
   static String translate(final BuildContext context, final String key,
       [final Map<String, String> translationParams]) {
     String translation = _translateWithKeyFallback(context, key);
@@ -72,7 +79,7 @@ class FlutterI18n {
 
   static String _translateWithKeyFallback(BuildContext context, String key) {
     final Map<String, dynamic> decodedStrings =
-        Localizations.of<FlutterI18n>(context, FlutterI18n).decodedMap;
+        retrieveCurrentInstance(context).decodedMap;
     final List<String> splittedKey = key.split(".");
     String translation = _decodeFromMap(decodedStrings, splittedKey);
     if (translation == null) {
@@ -81,6 +88,10 @@ class FlutterI18n {
     return translation;
   }
 
+  static FlutterI18n retrieveCurrentInstance(BuildContext context) {
+    return Localizations.of<FlutterI18n>(context, FlutterI18n);
+  }
+
   static String _decodeFromMap(
       Map<String, dynamic> decodedStrings, final List<String> splittedKey) {
     for (final String keyPart in splittedKey) {

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flutter_i18n
 description: i18n made easy for Flutter. With flutter_i18n you can make your app international, using just a simple .json file!
-version: 0.2.0
+version: 0.3.0
 author: Matteo Pietro Dazzi <[email protected]>
 homepage: https://github.com/ilteoood/flutter_i18n