Making a unit converter

import tkinter

screen = tkinter.Tk()

screen.title('Mile to km converter')

screen.minsize(width = 300, height = 150)

#blank

blank = tkinter.Label()

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

#is equal to

main_text = tkinter.Label(text = 'is equal to')

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

main_text.config(padx = 30)

#miles input

input = tkinter.Entry(width = 5)

input.grid(column=1, row = 1)

input_txt = tkinter.Label(text= 'Miles')

input_txt.grid(column = 2, row = 1)

#kilometer output

output = tkinter.Label(text = '')

output.grid(column=1,row=4)

output_txt = tkinter.Label(text= 'Km')

output_txt.grid(column = 2, row = 4)

#converter button

def button_action():

    km = float(input.get()) * 1.609

    output.config(text =km)

button = tkinter.Button(text = 'Calculate',command = button_action)

button.grid(column = 1,row=6)

screen.mainloop()

What I learned

• Can add image to screen:screen.addshape(image) turtle.shape(image)

  #first line tells screen image exists, second tells turtle to wear it

• list comprehension

  new_list = [new_item for item in list]

• conditional list comprehension:

  new_list = [new_item for item in list if list]

• dictionary comprehension:

  new_dict = {new_key: new_value for item in list}

  new_dict = {new_key:new_value for (key,value) in dict.items()}

• Can loop through rows of a data frame:

  for (index, row) in data_dict.iterrows():

       print(row.key)

• label centering and making it actually appear on screen in tkinter

my_label.pack(side = 'bottom','right''left')/ my_label.pack(expanse = True)

• *args: can accept any number of arguments

sum_ = 0def add(*args):    global sum_    for num in args:        sum_ += num    print(sum_)add(1,2,3,4)

• **kwargs: keyword arguments, in the form of dictionaries

• .get() function:

  when retrieving values from a dictionary with keys, use square brackets to indicate key. But in this case, if there is no value for the key, it will create an error. To prevent this, use the .get() function

  ex) from **kw

  kw.get('girl')

  even if there is no key for 'girl' it will just return None

• #label configuration

  my_label['text'] = 'New text' #changing im a label to new text

  my_label.config(text = 'New text') #same as above

• When inserting a function as arguments, can remove parenthesises :

button = tkinter.Button(text = 'click me', command=button_clicked)

• Entry(basically input):

input = tkinter.Entry(width = 10)input.pack()input.get() -> this is the value of the user's input

• tkinter pack(): with every pack() called, will enter the widget right under the previous widget

• tkinter position function 2.: place()

  Can place exact coordinates. Move with + values only, the top left corner being (0,0)

• tkinter position function 3.: grid()

  Can create grids by rows and columns and place it in order

• The positon functions cannot be used together- just use one till the end

• grid(): Don't really think about how it is divided. Have to count from 0, the first column and row are 0

• Creating padding/borders: with the screen(), do screen.config(padx =, pady = )

screen.config(padx = 20, pady= 20)