Bugfix in custom z-level setup

errors.py

@@ -25,7 +25,4 @@ class InvalidParticleError(Exception):
 
 
 class NotConnectedContoursError(Exception):
-    pass
-
-class ValueNotSetError(Exception):
     pass
\ No newline at end of file

opticalscan.py

@@ -559,7 +559,11 @@ class OpticalScan(QtWidgets.QWidget):
         softwarez = self.ramanctrl.getSoftwareZ()  # get current software z
         points[:,2] += softwarez-self.ramanctrl.getUserZ()
 
-        zrange = self.zLevelSetter.getZLevels()
+        try:
+            zrange = self.zLevelSetter.getZLevels()
+        except ValueError:
+            return
+
         zmaxstack = max(zrange)
         if len(zrange) == 1:
             zmaxstack = 0.0

zlevelsetter.py

@@ -7,7 +7,6 @@ Created on Fri Oct 25 09:39:14 2019
 from PyQt5 import QtWidgets, QtCore
 import sys
 import numpy as np
-from .errors import ValueNotSetError
 
 
 class ZLevelSetter(QtWidgets.QLabel):
@@ -251,9 +250,9 @@ class ZLevelSetter(QtWidgets.QLabel):
         elif self.customChecker.isChecked():
             try:
                 zLevels = self._getCustomLevels()
-            except ValueNotSetError:
+            except ValueError:
                 QtWidgets.QMessageBox.critical(self, 'Error', 'Invalid entry in custom level selection')
-                return
+                raise ValueError
         return np.array(zLevels)
 
     def _getCustomLevels(self):
@@ -266,7 +265,7 @@ class ZLevelSetter(QtWidgets.QLabel):
             try:
                 levels.append(float(lineEdit.text()))
             except:
-                raise ValueNotSetError
+                raise ValueError
         return sorted(levels)