fix kivy not updating units in history

gui/kivy/uix/screens.py

@@ -144,7 +144,7 @@ class HistoryScreen(CScreen):
         ri.date = status_str
         ri.message = label
         ri.value = value or 0
-        ri.value_known = value is not None
+        ri.amount = self.app.format_amount(value, True) if value is not None else '--'
         ri.confirmations = conf
         if self.app.fiat_unit and date:
             rate = self.app.fx.history_rate(date)

gui/kivy/uix/ui_screens/history.kv

@@ -20,8 +20,7 @@
     icon: 'atlas://gui/kivy/theming/light/important'
     message: ''
     value: 0
-    value_known: True
-    amount: app.format_amount(self.value, True) if self.value_known else '--'
+    amount: '--'
     amount_color: '#FF6657' if self.value < 0 else '#2EA442'
     confirmations: 0
     date: ''