Make some strings translatable

Instead of hard-coding the strings.

assets/langs/en.yaml

@@ -36,3 +36,29 @@ actions:
   newNote: New Note
   newJournal: New Journal Entry
   newChecklist: New Checklist
+screens:
+  folders:
+    title: Folders
+    selected: Folder Selected
+    dialog:
+      title: Create new Folder
+      create: Create
+      discard: Discard
+    errorDialog:
+      title: Error
+      content: Cannot delete a Folder which contains notes
+      ok: Ok
+    actions:
+      rename: Rename Folder
+      subFolder: Create Sub-Folder
+      delete: Delete Folder
+      decoration: Folder Name
+      empty: Please enter a name
+widgets:
+  rename:
+    yes: Rename
+    no: Cancel
+    validator:
+      empty: Please enter a name
+      exists: Already Exists
+      contains: Cannot contain /

lib/screens/folder_listing.dart

@@ -1,3 +1,4 @@
+import 'package:easy_localization/easy_localization.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
@@ -51,16 +52,16 @@ class _FolderListingScreenState extends State<FolderListingScreen> {
       action = PopupMenuButton(
         itemBuilder: (context) {
           return [
-            const PopupMenuItem<String>(
+            PopupMenuItem<String>(
-              child: Text("Rename Folder"),
+              child: Text(tr("screens.folders.actions.rename")),
               value: "Rename",
             ),
-            const PopupMenuItem<String>(
+            PopupMenuItem<String>(
-              child: Text("Create Sub-Folder"),
+              child: Text(tr("screens.folders.actions.subFolder")),
               value: "Create",
             ),
-            const PopupMenuItem<String>(
+            PopupMenuItem<String>(
-              child: Text("Delete Folder"),
+              child: Text(tr("screens.folders.actions.delete")),
               value: "Delete",
             ),
           ];
@@ -71,8 +72,8 @@ class _FolderListingScreenState extends State<FolderListingScreen> {
               context: context,
               builder: (_) => RenameDialog(
                 oldPath: selectedFolder.folderPath,
-                inputDecoration: 'Folder Name',
+                inputDecoration: tr("screens.folders.actions.decoration"),
-                dialogTitle: "Rename Folder",
+                dialogTitle: tr("screens.folders.actions.rename"),
               ),
             );
             if (folderName is String) {
@@ -115,9 +116,9 @@ class _FolderListingScreenState extends State<FolderListingScreen> {
       },
     );
 
-    var title = const Text("Folders");
+    var title = Text(tr('screens.folders.title'));
     if (selectedFolder != null) {
-      title = const Text("Folder Selected");
+      title = Text(tr("screens.folders.selected"));
     }
 
     return Scaffold(
@@ -173,9 +174,11 @@ class _CreateFolderAlertDialogState extends State<CreateFolderAlertDialog> {
         mainAxisSize: MainAxisSize.min,
         children: <Widget>[
           TextFormField(
-            decoration: const InputDecoration(labelText: 'Folder Name'),
+            decoration: InputDecoration(
+              labelText: tr("screens.folders.actions.decoration"),
+            ),
             validator: (value) {
-              if (value.isEmpty) return 'Please enter a name';
+              if (value.isEmpty) return tr("screens.folders.actions.empty");
               return "";
             },
             autofocus: true,
@@ -188,18 +191,18 @@ class _CreateFolderAlertDialogState extends State<CreateFolderAlertDialog> {
     );
 
     return AlertDialog(
-      title: const Text("Create new Folder"),
+      title: Text(tr("screens.folders.dialog.title")),
       actions: <Widget>[
         FlatButton(
           onPressed: () => Navigator.of(context).pop(false),
-          child: const Text("Discard"),
+          child: Text(tr("screens.folders.dialog.create")),
         ),
         FlatButton(
           onPressed: () {
             var newFolderName = _textController.text;
             return Navigator.of(context).pop(newFolderName);
           },
-          child: const Text("Create"),
+          child: Text(tr("screens.folders.dialog.discard")),
         ),
       ],
       content: form,
@@ -217,11 +220,11 @@ class FolderErrorDialog extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return AlertDialog(
-      title: const Text("Error"),
+      title: Text(tr("screens.folders.errorDialog.title")),
-      content: const Text("Cannot delete a Folder which contains notes"),
+      content: Text(tr("screens.folders.errorDialog.content")),
       actions: <Widget>[
         FlatButton(
-          child: const Text("Ok"),
+          child: Text(tr("screens.folders.errorDialog.ok")),
           onPressed: () => Navigator.of(context).pop(),
         ),
       ],

lib/widgets/rename_dialog.dart

@@ -1,5 +1,6 @@
 import 'dart:io';
 
+import 'package:easy_localization/easy_localization.dart';
 import 'package:flutter/material.dart';
 import 'package:path/path.dart';
 import 'package:path/path.dart' as p;
@@ -40,17 +41,17 @@ class _RenameDialogState extends State<RenameDialog> {
             decoration: InputDecoration(labelText: widget.inputDecoration),
             validator: (value) {
               if (value.isEmpty) {
-                return 'Please enter a name';
+                return tr('widgets.rename.validator.empty');
               }
 
               if (value.contains(p.separator)) {
-                return 'Cannot contain ${p.separator}';
+                return tr('widgets.rename.validator.contains');
               }
 
               var newPath = join(dirname(widget.oldPath), value);
               if (FileSystemEntity.typeSync(newPath) !=
                   FileSystemEntityType.notFound) {
-                return 'Already Exists';
+                return tr('widgets.rename.validator.exists');
               }
               return null;
             },
@@ -68,7 +69,7 @@ class _RenameDialogState extends State<RenameDialog> {
       actions: <Widget>[
         FlatButton(
           onPressed: () => Navigator.of(context).pop(false),
-          child: const Text("Cancel"),
+          child: Text(tr('widgets.rename.no')),
         ),
         FlatButton(
           onPressed: () {
@@ -77,7 +78,7 @@ class _RenameDialogState extends State<RenameDialog> {
               Navigator.of(context).pop(newName);
             }
           },
-          child: const Text("Rename"),
+          child: Text(tr('widgets.rename.yes')),
         ),
       ],
       content: form,