Show version name in settings, fix progress bar when purchase ended wit error

lib/screens/purchase.dart

@@ -386,6 +386,9 @@ class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {
         }
 
         if (purchase.containsKey('errors')) {
+          setState(() {
+            loading = false;
+          });
           List<String> errors = purchase['errors'];
           purchaseInProgress = false;
           apiErrorAlert(errors[0]);

lib/screens/settings.dart

@@ -39,6 +39,7 @@ class SettingsState extends BaseState<SettingsScreen> {
   ];
 
   bool returnToScanner;
+  String versionName = "";
 
   bool isAutomaticallyImplyLeading() => true;
 
@@ -46,12 +47,14 @@ class SettingsState extends BaseState<SettingsScreen> {
     this.returnToScanner = returnToScanner;
   }
 
-  @override
-  void initState() {
-    super.initState();
-  }
-
   @override Widget build(BuildContext ctx) {
+    if (this.versionName == "") {
+      platform.invokeMethod('getVersionName').then((versionName) {
+        setState(() {
+          this.versionName = versionName;
+        });
+      });
+    }
     // TODO: Перенести в initStater
     helper.getSettings(true).then((info) {
       setState(() {
@@ -204,6 +207,6 @@ class SettingsState extends BaseState<SettingsScreen> {
 
   @override
   String getTitle() {
-    return StringsLocalization.settings();
+    return StringsLocalization.settings() + " ($versionName)";
   }
 }