#!/usr/bin/env python

# Written by: DGC

from Tkinter import *

import random

#==============================================================================

class Model(object):

def __init__(self):

# q_and_a is a dictionary where the key is a question and the entry is

# a list of pairs, these pairs are an answer and whether it is correct

self.q_and_a = {

"How many wives did Henry VIII have?": [

("Five", False),

("Six", True),

("Seven", False),

("Eight", False)

],

"In which Italian city is Romeo and Juliet primarily set?": [

("Verona", True),

("Naples", False),

("Milano", False),

("Pisa", False)

],

"A light year is a measure of what?": [

("Energy", False),

("Speed", False),

("Distance", True),

("Intensity", False)

]

}

def question_and_answers(self):

"""

Returns a randomly chosen question (string) and answers (list of

strings) as a pair.

"""

key = random.choice(self.q_and_a.keys())

return (key, [x[0] for x in self.q_and_a[key]])

def is_correct(self, question, answer):

answers = self.q_and_a[question]

for ans in answers:

if (ans[0] == answer):

return ans[1]

assert False, "Could not find answer."

#==============================================================================

class View(object):

def __init__(self):

self.parent = Tk()

self.parent.title("Trivia")

self.initialise_ui()

self.controller = None

def clear_screen(self):

""" Clears the screen deleting all widgets. """

self.frame.destroy()

self.initialise_ui()

def initialise_ui(self):

self.answer_button = None

self.continue_button = None

self.frame = Frame(self.parent)

self.frame.pack()

def new_question(self, question, answers):

"""

question is a string, answers is a list of strings

e.g

view.new_question(

"Is the earth a sphere?",

["Yes", "No"]

)

"""

self.clear_screen()

# put the question on as a label

question_label = Label(self.frame, text=question)

question_label.pack()

# put the answers on as a radio buttons

selected_answer = StringVar()

selected_answer.set(answers[0])

for answer in answers:

option = Radiobutton(

self.frame,

text=answer,

variable=selected_answer,

value=answer,

)

option.pack()

# button to confirm

answer_function = lambda : self.controller.answer(

question,

selected_answer.get()

)

self.answer_button = Button(

self.frame,

text="Answer",

command=answer_function

)

self.answer_button.pack()

def main_loop(self):

mainloop()

def register(self, controller):

""" Register a controller to give callbacks to. """

self.controller = controller

def feedback(self, feedback):

self.clear_screen()

label = Label(self.frame, text=feedback)

label.pack()

self.continue_button = Button(

self.frame,

text="Continue",

command=self.controller.next_question

)

self.continue_button.pack()

#==============================================================================

class Controller(object):

def __init__(self, model, view):

self.model = model

self.view = view

self.view.register(self)

self.new_question()

def new_question(self):

q_and_a = self.model.question_and_answers()

self.view.new_question(q_and_a[0], q_and_a[1])

def next_question(self):

self.new_question()

def answer(self, question, answer):

correct = self.model.is_correct(question, answer)

feedback = ""

if (correct):

feedback = "That is correct."

else:

feedback = "Sorry that's wrong."

self.view.feedback(feedback)

#==============================================================================

if (__name__ == "__main__"):

# Note: The view should not send to the model but it is often useful

# for the view to receive update event information from the model.

# However you should not update the model from the view.

view = View()

model = Model()

controller = Controller(model, view)

view.main_loop()