Исправлено падение приложения из-за попытки сделать запрос к бд, после закрытия соединения с ней

lib/common.dart

@@ -40,11 +40,11 @@ logout(BuildContext context, SqliteHelper helper) async {
     if (token != null) {
       getDeleteTokenRequest(token).then((response) {
         helper.clear().then((result) {
-          helper.close().then((_) {
+//          helper.close().then((_) {
             Navigator.of(context).pop();
             Navigator.of(context).pop();
             pushRouteReplacement(context, new SplashScreen()); // Запускаем регистрацию
-          });
+//          });
         });
       }).catchError((error) {
         print(error.toString());
@@ -63,12 +63,12 @@ forceLogout(String token , BuildContext context) async {
     SqliteHelper helper = new SqliteHelper();
     helper.open().then((_) {
       helper.clear().then((_) {
-        helper.close().then((_) {
+//        helper.close().then((_) {
           while (Navigator.of(context).canPop()) {
             Navigator.of(context).pop();
           }
           pushRouteReplacement(context, new SplashScreen());
-        });
+//        });
       });
     });
   }).catchError((error) {
@@ -117,8 +117,8 @@ startScanner(BuildContext context, String app, SqliteHelper helper) async {
         }
       });
 
-      helper.close().then((_){
-        helper = null;
+//      helper.close().then((_){
+//        helper = null;
         platform.invokeMethod('getEndpoint').then((endpoint) {
           platform.invokeMethod('getAppToken').then((appToken) async {
             platform.invokeMethod('startScanner', {
@@ -126,13 +126,11 @@ startScanner(BuildContext context, String app, SqliteHelper helper) async {
               'url': endpoint,
               'appToken': appToken,
               'locale': Intl.defaultLocale,
-              'color': Resources
-                  .getPrimaryColor(app)
-                  .value
+              'color': Resources.getPrimaryColor(app).value
             });
           });
         });
-      });
+//      });
     }
   }
 }

lib/db.dart

@@ -137,7 +137,4 @@ class SqliteHelper {
   Future clear() async {
     return await db.delete(tableSession, where: null);
   }
-
-  Future close() async => db.close();
-
 }

lib/screens/settings.dart

@@ -28,10 +28,7 @@ class MenuItem {
 
 class SettingsState extends BaseState<SettingsScreen> {
 
-  List<MenuItem> menuItems = [
-    new MenuItem('', ''),
-    new MenuItem('', '')
-  ];
+  List<MenuItem> menuItems;
 
   bool returnToScanner;
 
@@ -42,14 +39,22 @@ class SettingsState extends BaseState<SettingsScreen> {
   }
 
   @override Widget build(BuildContext ctx) {
-    helper.getSettings().then((info) {
-      setState(() {
-        menuItems[0].title = StringsLocalization.currency();
-        menuItems[1].title = StringsLocalization.locale();
-        menuItems[0].selectedValue = info['currency'].toString();
-        menuItems[1].selectedValue = info['locale'] == null ? Intl.defaultLocale : info['locale'].toString();
+    if (menuItems == null) {
+      menuItems = [
+        new MenuItem('', ''),
+        new MenuItem('', '')
+      ];
+      helper.getSettings().then((info) {
+        setState(() {
+          menuItems[0].title = StringsLocalization.currency();
+          menuItems[1].title = StringsLocalization.locale();
+          menuItems[0].selectedValue = info['currency'].toString();
+          menuItems[1].selectedValue =
+          info['locale'] == null ? Intl.defaultLocale : info['locale']
+              .toString();
+        });
       });
-    });
+    }
     return new WillPopScope(onWillPop: onWillPop, child: getMainWidget());
   }
 
@@ -72,11 +77,16 @@ class SettingsState extends BaseState<SettingsScreen> {
 
   List<Widget> getSettings() {
     List<Widget> widgets = new List();
-    for (int i = 0; i < menuItems.length; i++) {
-      if (menuItems[i].selectedValue != '') {
-        widgets.add(getSettingsItem(() => onPressed(menuItems.indexOf(menuItems[i])),
-            menuItems[i].title,
-            i == 0 ? getCurrencyTitle(int.parse(menuItems[i].selectedValue)) : getLocaleTitle(menuItems[i].selectedValue)));
+    if (menuItems != null) {
+      for (int i = 0; i < menuItems.length; i++) {
+        if (menuItems[i].selectedValue != '') {
+          widgets.add(
+              getSettingsItem(() => onPressed(menuItems.indexOf(menuItems[i])),
+                  menuItems[i].title,
+                  i == 0 ? getCurrencyTitle(
+                      int.parse(menuItems[i].selectedValue)) : getLocaleTitle(
+                      menuItems[i].selectedValue)));
+        }
       }
     }
     return widgets;
@@ -105,8 +115,10 @@ class SettingsState extends BaseState<SettingsScreen> {
   void onPressed(int position) {
     switch (position) {
       case 0 :
+        menuItems = null;
         return pushRoute(context, new CurrenciesScreen(helper, app));
       case 1 :
+        menuItems = null;
         return pushRoute(context, new LanguagesScreen(helper, app));
     }
   }

lib/screens/splash.dart

@@ -129,7 +129,7 @@ class _SplashScreenState extends BaseState<SplashScreen> {
         getCheckTokenStatusRequest(token).then((statusResponse) {
           handleStatusResponse(statusResponse, helper);
         }).catchError((error) {
-          handleError(error.toString());
+          print(error.toString());
         });
       }
     }
@@ -179,7 +179,7 @@ class _SplashScreenState extends BaseState<SplashScreen> {
         clearToken(response, helper);
       }
     }).catchError((error) {
-      handleError(error.toString());
+      print(error.toString());
     });
   }
 
@@ -191,16 +191,8 @@ class _SplashScreenState extends BaseState<SplashScreen> {
         Navigator.of(context).pop();
         pushRouteReplacement(context, new RegistrationScreen(helper, app));
       }).catchError((error) {
-        handleError(error.toString());
+        print(error.toString());
       });
     });
   }
-
-  /// Закрываем соединение, логируем ошибку.
-  void handleError(String error) {
-    helper.close().then((_) {
-      print(error.toString());
-      return false;
-    });
-  }
 }