add condition to prevent no value added to the value_color_str; modify range...

add condition to prevent no value added to the value_color_str; modify range of BoundValidator to -10,10; modify docstring

sohstationviewer/view/db_config/value_color_helper/edit_value_color_dialog/multi_color_dot_dialog.py

 import sys
 import platform
 import os
-
 from typing import List, Dict
 
 from PySide2 import QtWidgets, QtCore, QtGui
@@ -17,7 +16,10 @@ TOTAL = 7
 
 class BoundValidator(QtGui.QValidator):
     """
-    Validator that allow float value and empty string
+    Validator that allow float value and empty string.
+    Range of value is from -10, 10 because -20/20 are the values assigned to
+        higher bounds of the previous/next when the current row is 0 and last
+        so the editable higher bounds can't ever be reached to.
     Value '-'  to allow typing negative float. If user type '-' only, it will
         be checked when editing is finished.
     """
@@ -28,7 +30,7 @@ class BoundValidator(QtGui.QValidator):
             input = float(input)
         except ValueError:
             return QtGui.QValidator.Invalid
-        if -20 <= input <= 20:
+        if -10 <= input <= 10:
             return QtGui.QValidator.Acceptable
         else:
             return QtGui.QValidator.Invalid
@@ -61,6 +63,9 @@ class MultiColorDotDialog(EditValueColorDialog):
         # After a higher bound widget is edited and enter is hitted, button's
         # clicked signal will be called before higher_bound_editting_finished
         # is reached. The following flags are to change that order.
+        # These flags are also used to prevent the case hitting Select Color or
+        # Save right after user done with editing. In case there is error when
+        # checking the value, the button click will be canceled too.
         self.changed_rowid = None
         self.select_color_btn_clicked = False
         self.save_colors_btn_clicked = False
@@ -127,15 +132,16 @@ class MultiColorDotDialog(EditValueColorDialog):
         Check value entered for higher bound:
             + If the last row is empty string, that value will be eliminated
                 from condition.
-            + If other row is empty string, give error message
             + If value not greater than previous row and less than latter row,
                 give error message. -20 and 20 are given to previous or latter
                 row if not exist b/c they are out of range of bound [-10, 10]
         Call set_value_rowid_dict to keep track of value by rowid.
+
+        :param rowid: rowid is
         """
         if self.changed_rowid is None:
             # When the function isn't called from user's changing text on
-            # a higher_bound_lnedit, this function will be ignored
+            # a higher_bound_lnedit, this function will be ignored.
             return
 
         if len(self.rowid_value_dict) < self.changed_rowid < TOTAL - 1:
@@ -164,6 +170,13 @@ class MultiColorDotDialog(EditValueColorDialog):
             else:
                 # If the cleared one is the last one, the lower_bound_lnedit
                 # of the next row will be cleared too.
+                if rowid == 0:
+                    # If the cleared one is the only one, this shouldn't be
+                    # allowed. A warning should be given.
+                    msg = ("There should be at least one value"
+                           " for this plot type.")
+                    QtWidgets.QMessageBox.information(self, "Error", msg)
+                    return
                 self.set_color_enabled(rowid, False)
                 self.lower_bound_lnedits[rowid + 1].setText('')
                 self.set_value_rowid_dict()
@@ -302,7 +315,6 @@ class MultiColorDotDialog(EditValueColorDialog):
                 value<:color
         """
         if self.changed_rowid and self.changed_rowid < TOTAL - 1:
-            print("on_save_color")
             self.save_colors_btn_clicked = True
             self.on_higher_bound_editing_finished(self.changed_rowid)
             return
@@ -358,7 +370,8 @@ class MultiColorDotLowerEqualDialog(MultiColorDotDialog):
         self.main_layout.addWidget(QtWidgets.QLabel(comp_text), rowid, 2, 1, 1)
 
         higher_bound_lnedit = QtWidgets.QLineEdit()
-        validator = BoundValidator()
+        validator = BoundValidator
+
         higher_bound_lnedit.setValidator(validator)
         self.main_layout.addWidget(higher_bound_lnedit, rowid, 3, 1, 1)
         if rowid == TOTAL - 1:
@@ -485,4 +498,5 @@ if __name__ == '__main__':
     test = MultiColorDotUpperEqualDialog(
         None, '<=0:not plot|<=1:#FFFF00|<=2:#00FF00|2<:#FF00FF')
     test.exec_()
-    sys.exit(app.exec_())
+    print("result:", test.value_color_str)
+    sys.exit(app.exec_())
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