numberbar: no float values from mouse

gui/container/numberbar.py

@@ -30,7 +30,7 @@ class NumberBarContainer(FocusSwitcher):
         """Set the progress to the approx mouse position in ProgressBar."""
         p = self._get_progressbar()
         if p.row - 1 <= my <= p.row + p.height and p.col - 1 <= mx <= p.col + p.width:
-            val = 255 - (my - p.row) / p.height * 255
+            val = int(255 - (my - p.row) / p.height * 255)
             self._get_numberrange().set(val)
             p.set(val)