Question

I need trying to figure out how I can make create a code in Python with this exercise for I am having trouble doing so.

Miles Per Gallon Calculator Write a GUI program that calculates a car's gas mileage. The program's window should have Entry widgets that let the user enter the number of gallons of gas the car holds, and the number of miles it can be driven on a full tank. When a Calculate MPG button is clicked, the program should display the number of miles that the car may be driven per gallon of gas. Use the following formula to calculate miles-per-gallon MPG-miles/gallons

Answer 1

Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

#code

from tkinter import *

#method to calculate MPG and display it
def calculate():
    try:
        #fetching values from StringVar objects (see below) and converting
        #values to float
        miles=float(milesTxt.get())
        gallons=float(gallonsTxt.get())
        #finding mpg
        mpg=miles/gallons
        #displaying it on mpgTxt StringVar, which will set the linked Label
        mpgTxt.set('{:.2f} miles/gallon'.format(mpg))
    except:
        #error occurred while parsing
      mpgTxt.set('Invalid input!')

#creating root window
root=Tk()

#creating three StringVar objects. that can be used to get and set
#values in Label and Entry objects
gallonsTxt=StringVar()
milesTxt=StringVar()
mpgTxt=StringVar()

#creating Labels and Entrys as needed, aligning them using grid layout
Label(root,text='Enter number of gallons: ').grid(row=0,column=0)
#defining Entry for gallons, and mapping to the gallonsTxt StringVar
Entry(root,textvariable=gallonsTxt).grid(row=0,column=1)

Label(root,text='Enter number of miles: ').grid(row=1,column=0)
Entry(root,textvariable=milesTxt).grid(row=1,column=1)

#defining the button to call calculate method on click
Button(root,text='Calculate MPG',command=calculate).grid(row=2,column=0)
Label(root,textvariable=mpgTxt).grid(row=3,column=0)

#staying until user quits
root.mainloop()

#output

tk Enter number of gallons: 20 Enter number of miles: 250 Calculate MPG 12.50 miles/gallon