toga-tutorial/fc_converter.py at main · snakebyte-dev/toga-tutorial · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
import toga
from toga.constants import COLUMN, LEFT, RIGHT, ROW


def build(app):
   # Fahrenheit box and widgets
   f_box = toga.Box()
   f_input = toga.TextInput()
   f_label = toga.Label("Fahrenheit", text_align=LEFT)

   # Celsius box and widgets
   c_box = toga.Box()
   c_input = toga.TextInput(readonly=True)
   c_label = toga.Label("Celsius", text_align=LEFT)
   join_label = toga.Label("is equivalent to", text_align=RIGHT)

   # Calculate button
   def calculate(widget):
       try:
           c_input.value = (float(f_input.value) - 32.0) * 5.0 / 9.0
       except ValueError:
           c_input.value = "???"

   button = toga.Button("Calculate", on_press=calculate)

   # Add widgets to boxes
   f_box.add(f_input)
   f_box.add(f_label)

   c_box.add(join_label)
   c_box.add(c_input)
   c_box.add(c_label)

   # Main box
   box = toga.Box()
   box.add(f_box)
   box.add(c_box)
   box.add(button)

   # Styles
   box.style.update(direction=COLUMN, margin=10, gap=10)
   f_box.style.update(direction=ROW, gap=10)
   c_box.style.update(direction=ROW, gap=10)

   c_input.style.update(flex=1)
   f_input.style.update(flex=1, margin_left=210)
   c_label.style.update(width=100)
   f_label.style.update(width=100)
   join_label.style.update(width=200)

   button.style.update(margin_top=5)

   return box


def main():
   return toga.App(
       "Temperature Converter",
       "org.beeware.toga.examples.tutorial",
       startup=build,
   )


if __name__ == "__main__":
   main().main_loop()