Having problems using Tkinter

[viv1tyagi at gmail.com]

Hi everyone ! ! !

I'm just a month old in the world of Python and trying to develop an
application using Tkinter in which a new window pops out on a
particular button press.The code for this new window is in
"AddKlas.py" file.
The  problem is  all the content of the new window is overwritten on
the previous window.
Below is the code of the two files

PLEASE help me out ! ! ! !

#1st file
#Klass.py
from Tkinter import *
import AddKlass
class Klass(Frame):
    def __init__(self):
        self.labels()
        self.buttons()
        self.menubuttons()
        self.scrollandcanvas()


    def labels(self):
        label1=Label(relief='groove',text=" Class
Id",width=20,anchor=W)
        label1.grid(row=0,column=0)
        label2=Label(relief='groove',text=" Class
Name",width=20,anchor=W)
        label2.grid(row=0,column=1)
        label3=Label(relief='groove',text=" Class Room
No.",width=20,anchor=W)
        label3.grid(row=0,column=2)
        label4=Label(relief='groove',text=" Category
Id",width=80,anchor=W)
        label4.grid(row=0,column=3)

    def buttons(self):
        button1=Button(text="Add",width=10,command=self.CallAdd)
        button1.grid(row=2,column=5)
        button2=Button(text="View",width=10,state=DISABLED)
        button2.grid(row=3,column=5)
        button3=Button(text="Next",width=10,state=DISABLED)
        button3.grid(row=4,column=5)

    def menubuttons(self):
        menubutton=Menubutton(text="Options",width=10,relief="raised")
        menubutton.grid(row=5,column=5)
        menubutton.menu=Menu(menubutton)
        menubutton["menu"]=menubutton.menu
        menubutton.menu.add_command(label="Modify")
        menubutton.menu.add_command(label="Delete")

    def scrollandcanvas(self):
        yscroll=Scrollbar()
        yscroll.grid(row=1,column=4,rowspan=7,sticky=N+S)
        canva=Canvas(bg="#fff",yscrollcommand=yscroll.set)
        canva.grid(row=1,column=0,rowspan=7,columnspan=4,sticky=N+E+S
+W)

    def CallAdd(self):
        AddKlass.root=Tk()
        AddKlass.AddKlas()
        AddKlass.root.focus_force()
        AddKlass.root.geometry("275x250")
        AddKlass.root.title("Add Class Information")
        AddKlass.root.resizable(width=False,height=False)
        AddKlass.root.mainloop()

root=Tk()
app = Klass()
root.geometry("960x300")
root.title("Class Information")
root.resizable(width=False,height=False)
root.mainloop()




#2nd file
#AddKlass.py
from Tkinter import *

class AddKlas(Frame):
    #root=None
    def __init__(self):
        self.labels()
        self.buttons()
        self.entry()

    def labels(self):
        label1=Label(relief='flat',text=" Class
Id :",height=3,width=20)
        label1.grid()
        label2=Label(relief='flat',text=" Class
Name :",height=3,width=20)
        label2.grid()
        label3=Label(relief='flat',text=" Class Room
No. :",height=3,width=20)
        label3.grid()
        label4=Label(relief='flat',text=" Category
Id :",height=3,width=20)
        label4.grid()

    def buttons(self):
        button1=Button(text="Add",width=10,state=DISABLED)
        button1.grid(row=5,column=0)
        button2=Button(text="Cancel",width=10,command=self.quit)
        button2.grid(row=5,column=1)

    def entry(self):
        entry1=Entry()   #by default width =20
        entry1.grid(row=0,column=1)
        entry2=Entry()
        entry2.grid(row=1,column=1)
        entry3=Entry()
        entry3.grid(row=2,column=1)
        entry4=Entry()
        entry4.grid(row=3,column=1)

#root=Tk()
#app = AddKlas()
#root.geometry("275x250")
#root.title("Add Class Information")
#root.resizable(width=False,height=False)
#root.mainloop()