refactor swith language in a swith_language method

src/cutecoin/core/app.py

@@ -42,6 +42,7 @@ class Application(QObject):
         :param argv: The argv parameters of the call
         '''
         super().__init__()
+        self.qapp = qapp
         self.accounts = {}
         self.current_account = None
         self.monitor = None
@@ -57,8 +58,10 @@ class Application(QObject):
                             }
 
         self.load()
+        self.switch_language()
 
-        translator = QTranslator(qapp)
+    def switch_language(self):
+        translator = QTranslator(self.qapp)
         logging.debug("Loading translations")
         locale = self.preferences['lang']
         QLocale.setDefault(QLocale(locale))

src/cutecoin/gui/preferences.py

@@ -20,9 +20,11 @@ class PreferencesDialog(QDialog, Ui_PreferencesDialog):
     '''
 
     def __init__(self, app):
-        '''
-        Constructor
-        '''
+        """
+        Init instance
+        :param cutecoin.core.app.Application app:   Application instance
+        :return:
+        """
         super().__init__()
         self.setupUi(self)
         self.app = app