+ def up(self):
+ if self.text[self.currPos] == "9":
+ newNumber = "0"
+ else:
+ newNumber = str(int(self.text[self.currPos]) + 1)
+ self.text = self.text[0:self.currPos] + newNumber + self.text[self.currPos + 1:]
+ self.update()
+
+ def down(self):
+ if self.text[self.currPos] == "0":
+ newNumber = "9"
+ else:
+ newNumber = str(int(self.text[self.currPos]) - 1)
+ self.text = self.text[0:self.currPos] + newNumber + self.text[self.currPos + 1:]
+ self.update()
+
+ def delete(self):
+ self.text = self.text[:self.currPos] + self.text[self.currPos + 1:]
+ self.update()
+