Working with previous cases

import time

count = 5
while true:
		time.sleep()
		count -= 1

Event driven graphical user program

• Working with graphical user interface is a little bit different. It needs to keep watching the screen to see whether if a user clicks on a button.
• It's basically going to refresh and keep listening for events. So every fraction of a second, it's going to keep checking, did something happened did, and the moment when it does, then it's got to react.
• In this case, we tend to call these types of GUI programs event-driven
• The way that it's driven is through our main loop. it's basically looping through and every millisecond it's checking to see did something happen
• window.after It's a method that takes an amount of time that it should wait and then after that amount of time, it simply calls a particular function that you tell it to call passing in any arguments that you want to give it.

#1 
#you can see that after 1000 milliseconds, basically one second, 
#it calls this function, say_something, and it passes this hello as the input
#to that function.

def say_something(thing):
		print(thing)

window.after(1000, say_something, "Hello")
--------------------------------------
Hello

#2
#you can have an infinite amount of positional arguments.

def say_something(a, b, c):
		print(a)
		print(b)
		print(c)

window.after(1000, say_something, 3, 5 ,8)
--------------------------------------
3
5
8

Countdown

def count_down(count):
		if count > 0:		
				window.after(1000, count_down, count - 1)

count_down(5)

-------------
5
4
3
2
1
0

• To change a canvas element, you actually have to tap into the particular canvas you want to change and Then you call a method called itemconfig.
• In this method, you pass in the particular item that you actually want to configure, so in our case it's the timer_text
• Then you pass in the thing about it that you actually want to change in terms of a kwarg, so this is a keyword argument. We're going to change the text to the current count (text=count).

def count_down(count):
		canvas.itemconfig(timer_text, text=count)
		if count > 0:		
				window.after(1000, count_down, count - 1)

Start Timer as min:sec

• math.floor, is going to return the largest whole number that is less than or equal to x.

def start_timer():
    count_down(5*60)

# ---------------------------- COUNTDOWN MECHANISM ------------------------------- # 
def count_down(count):
    count_min = math.floor(count/60)
    count_sec = count % 60

    canvas.itemconfig(timer_text, text=f"{count_min}:{count_sec}")
    if count > 0:
        window.after(1000, count_down, count - 1)