I've written a simple script with TKinter and SQLAlchemy, where an sqlite .db is created, saving Employee information such as name, age, address, etc, etc.
I realized that if a user puts a string in the age and/or zip field (both fields require int's), an error will be thrown. So I put a try-except clause in the add_data method. If a string is placed in the age field for instance, the except clause will be thrown correctly and the showinfo window will appear with the error, but when the user clicks 'ok' on the box, an UnboundLocalError: local variable 'age' referenced before assignment error will show in IDLE.
I have read "https://docs.python.org/2/faq/programming.html#why-am-i-getting-an-unboundlocalerror-when-the-variable-has-a-value" and the other similar questions to no avail.
The data (employee info) will be saved correctly when the user corrects the mistake (puts an int the field & clicks the Add button). However, I obviously don't want this UnboundLocalError being thrown. I just don't know how to correct it, or why it's being thrown to begin with. . .Any help is greatly appreciated as always!
from datetime import datetime
from Tkinter import *
from tkMessageBox import *
import sqlite3, sqlalchemy
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, DateTime, Integer, String, MetaData
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
# map classes to tables through Base Class
Base = declarative_base()
class Employee(Base):
__tablename__ = 'employee'
id = Column(Integer, primary_key=True)
name = Column(String(250))
age = Column(Integer)
address = Column(String(250))
city = Column(String(10))
state = Column(String(2))
zip = Column(Integer)
ssn = Column(String(12))
phone = Column(String(12))
cell = Column(String(12))
# create engine for Session connection
engine = create_engine('sqlite:///employee.db',echo=True)
# create all tables in engine ('CREATE TABLE' in raw SQL)
Base.metadata.create_all(engine)
# create configured 'Session' class
Session = sessionmaker(bind=engine)
# create session
session = Session()
class GUI:
def __init__(self, parent):
self.parent = parent
# create top frame
frame = Frame(parent)
frame.pack(expand=YES, fill=BOTH, padx=5, pady=5)
# create bottom frame
btm_frame = Frame(parent, relief=SUNKEN, borderwidth=1)
btm_frame.pack(side=BOTTOM, expand=YES, fill=BOTH, padx=5, pady=5)
# create datetime object
d = datetime.today()
date = d.strftime("%Y-%m-%d")
#------------------------Create Labels-------------------------------#
# label to display date
date_label = Label(btm_frame, text=date)
date_label.pack(side=LEFT)
# name label
name_label = Label(frame, text="Enter Name:")
name_label.grid(row=0, sticky=W)
# age label
age_label = Label(frame, text="Enter Age:")
age_label.grid(row=1, sticky=W)
# address label
addr_label = Label(frame, text="Enter Address:")
addr_label.grid(row=2, sticky=W)
# city label
city_label = Label(frame, text="Enter City:")
city_label.grid(row=3, sticky=W)
# state label
state_label = Label(frame, text="Enter State:")
state_label.grid(row=4, sticky=W)
# zip code label
zip_label = Label(frame, text="Enter Zip Code:")
zip_label.grid(row=5, sticky=W)
# ssn label
ssn_label = Label(frame, text="Enter Social Security #:")
ssn_label.grid(row=6, sticky=W)
# phone label
phone_label = Label(frame, text="Enter Phone #:")
phone_label.grid(row=7, sticky=W)
# cell label
cell_label = Label(frame, text="Enter Cell #:")
cell_label.grid(row=8, sticky=W)
#----------------------Create Vars and Entry-------------------------#
# name variable and entry
self.name_var = StringVar()
self.e1 = Entry(frame, textvariable=self.name_var)
self.e1.grid(row=0, column=1)
# age variable and entry
self.age_var = IntVar()
self.e2 = Entry(frame, textvariable=self.age_var)
self.e2.grid(row=1, column=1)
# address variable and entry
self.address_var = StringVar()
self.e3 = Entry(frame, textvariable=self.address_var)
self.e3.grid(row=2, column=1)
# city variable and entry
self.city_var = StringVar()
self.e4 = Entry(frame, textvariable=self.city_var)
self.e4.insert(0, "Roanoke") # insert default value
self.e4.grid(row=3, column=1)
# state variable and entry
self.state_var = StringVar()
self.e5 = Entry(frame, textvariable=self.state_var)
self.e5.insert(0, "VA") # insert default value
self.e5.grid(row=4, column=1)
# zip code variable and entry
self.zip_var = IntVar()
self.e6 = Entry(frame, textvariable=self.zip_var)
self.e6.grid(row=5, column=1)
# s.s.n variable and entry
self.ssn_var = StringVar()
self.e7 = Entry(frame, textvariable=self.ssn_var)
self.e7.grid(row=6, column=1)
# phone variable and entry
self.phone_var = StringVar()
self.e8 = Entry(frame, textvariable=self.phone_var)
self.e8.grid(row=7, column=1)
# cell variable and entry
self.cell_var = StringVar()
self.e9 = Entry(frame, textvariable=self.cell_var)
self.e9.grid(row=8, column=1)
# quit, search, clear, add, delete buttons
quit_button = Button(btm_frame, text="Quit", relief=GROOVE, command=parent.destroy)
quit_button.pack(side=RIGHT)
search_button = Button(btm_frame, text="Search", relief=GROOVE, command=self.search)
search_button.pack(side=RIGHT, padx=1, pady=1)
clear_button = Button(btm_frame, text="Clear", relief=GROOVE, command=self.clear_entries)
clear_button.pack(side=RIGHT, padx=1, pady=1)
del_button = Button(btm_frame, text="Delete", relief=GROOVE, command=self.del_employee)
del_button.pack(side=RIGHT, padx=1, pady=1)
add_button = Button(btm_frame, text="Add", relief=GROOVE, command=self.add_data)
add_button.pack(side=RIGHT, padx=1, pady=1)
def add_data(self):
name = self.name_var.get()
try:
age = self.age_var.get()
except ValueError:
showinfo("Error:", "Please Enter A Number In Age Field.")
addr = self.address_var.get()
city = self.city_var.get()
state = self.state_var.get()
zip = self.zip_var.get()
ssn = self.ssn_var.get()
phone = self.phone_var.get()
cell = self.cell_var.get()
# create new Employee in .db
new_person = Employee(name=name, age=age, address=addr, city=city, state=state, zip=zip, ssn=ssn, phone=phone, cell=cell)
session.add(new_person)
session.commit()
session.close()
self.callback()
return
def callback(self):
showinfo("New Employee", "Data Added")
self.clear_entries()
return
def clear_entries(self):
entries = [self.e1, self.e2, self.e3, self.e4, self.e5, self.e6, self.e7, self.e8, self.e9]
for entry in entries:
entry.delete(0, END)
return
def search(self):
search_win = Toplevel()
search_win.title("Employee Search")
# create labels for each employee attribute
attr = ["Id","Name","Age","Address","City","State","Zip","SSN","Cell","Phone"]
column = 0
for a in attr:
Label(search_win, text=a).grid(row=0,column=column,padx=2, pady=2)
column += 1
# search all employees, put each emp. in Entry Widget with For Loop
res = session.query(Employee).all()
row = 1
column = 0
for employee in res:
txt = [employee.id, employee.name, employee.age, employee.address, employee.city, employee.state, employee.zip, employee.ssn, employee.phone, employee.cell]
for t in txt:
ent = Entry(search_win, relief=RIDGE, width=19)
ent.grid(row=row, column=column, sticky=W, padx=1, pady=1)
ent.insert(0, t)
column += 1
row += 1
column = 0
return
def del_employee(self):
del_win = Toplevel()
del_win.title("Delete Employee")
id_label = Label(del_win, text="Enter Employee Id:")
id_label.grid(row=0, column=0, padx=5, pady=5)
self.employee_id = IntVar()
self.e10 = Entry(del_win, textvariable=self.employee_id)
self.e10.grid(row=0, column=1, padx=5, pady=5)
del_button = Button(del_win, text="Delete Employee", relief=GROOVE, command=self.erase)
del_button.grid(row=0, column=2, padx=5, pady=5)
return
def erase(self):
emp_id = self.employee_id.get()
res = session.query(Employee).filter(Employee.id==emp_id).first()
session.delete(res)
session.commit()
showinfo("Employee", "Data Deleted")
return
if __name__ == '__main__':
root = Tk()
root.geometry("310x270")
root.title("Employee Info")
mygui = GUI(root)
root.mainloop()`
