Graphics User Interface for Beginners
 

Which Graphics User Interface (GUI) would you recommend for a beginner? I have seen some examples of Tkinter, wxPython and GTK.

Re: Graphics User Interface for Beginners
 

As a beginner, start working with Tkinter to get a feeling what GUI programming is all about. Tkinter is already present in the normal Python installation. If you need fancier widgets later, download wxPython and experiment with that. PyGTK/GTK works best with Linux, the Windows version needs a lot of additional downloads and the installation process is cumbersome.

Re: Graphics User Interface for Beginners
 

I will check Tkinter programming first. Any examples that show the difference between console and GUI programming?

Re: Graphics User Interface for Beginners
 

Here are simple programs. The console version:

# console sales tax program



while True:

    price = float(raw_input("Enter purchase price: "))

    # prevent division by zero error

    if price != 0:

        break

    else:

        print "price can not be zero!"

        

tax = float(raw_input("Enter sales tax paid: "))



percent = 100 * tax / price

print "You paid %0.3f%s sales tax" % (percent, '%')

Now the Tkinter GUI version:

# Tkinter sales tax program



from Tkinter import *

import tkSimpleDialog



# the basic window

root = Tk()

# create label for result

label1 = Label(root)

# position the label in window

label1.grid(row=0, column=0)

# ask for needed data with dialog window

# the askfloat dialog window makes certain you entered floating point value

# and also prevents you from entering zero which would give divide by zero error

price = tkSimpleDialog.askfloat("Price", "Enter purchase price:", parent=root, minvalue=0.01)

tax = tkSimpleDialog.askfloat("Tax", "Enter sales tax paid:", parent=root)

percent = 100 * tax / price

result = "You paid %0.3f%s sales tax" % (percent, '%')

# display result string in label1

label1.config(text=result)

# event loop needed by GUI, checks for mouse and key events

root.mainloop()

Re: Graphics User Interface for Beginners
 

Here is the Tkinter sales tax program without the dialog popups ...

# a rather generic Tkinter GUI template for calculations

# uses Entry() for data input and Button() to start calculation



from Tkinter import *



def calculate():

    try:

        # get the enter1 and enter2 values

        price = float(enter1.get())

        tax = float(enter2.get())

        # do the calculation

        percent = 100 * tax / price

        result = "You paid %0.3f%s sales tax" % (percent, '%')

        # display the result string

        label3.config(text=result)

    except ValueError:

        label3.config(text='Enter numeric values!')

    except ZeroDivisionError:

        label3.config(text='Price can not be zero!')

        enter1.focus_set()



root = Tk()

# window geometry is width x height + x_offset + y_offset

root.geometry("200x150+30+30")



# first entry with label

label1 = Label(root, text='Enter purchase price:')

label1.grid(row=0, column=0)

enter1 = Entry(root, bg='yellow')

enter1.grid(row=1, column=0)



# second entry with label

label2 = Label(root, text='Enter sales tax paid:')

label2.grid(row=2, column=0)

enter2 = Entry(root, bg='yellow')

enter2.grid(row=3, column=0)



# do the calculation by clicking the button

btn1 = Button(root, text='Calculate Percent', command=calculate)

btn1.grid(row=4, column=0)



# display the result in this label

label3 = Label(root)

label3.grid(row=5, column=0)



# start cursor in enter1

enter1.focus()

# value has been entered in enter1 now switch focus to enter2

enter1.bind('<Return>', func=lambda e: enter2.focus_set())



root.mainloop()