我正在尝试编写一个带有gui的程序，该程序将以三角形的3个边作为输入并输出该区域。我希望实时输出（以便无需用户按下任何执行按钮即可更新区域）。我是新手，但是我不知道如何管理输入和输出。任何帮助将不胜感激。
import kivy
from kivy.lang import Builder
from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.core.window import Window
from kivy.graphics import *
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition, NoTransition
from kivy.uix.textinput import TextInput
Builder.load_string('''
#:kivy 1.10.1
<MainScreen>:
Widget:
pos_hint:{'x': 0, 'right': 1}
size_hint: 2,2.1
canvas:
Color:
rgb: [0.09,0.1372,0.2,1]
Rectangle:
pos: self.pos
size: self.size
Widget:
pos_hint:{'x': 1, 'right': 0.35}
size_hint: 0.6,1
canvas:
Color:
rgb: [0.8,0.8,0.8,1]
Rectangle:
pos: self.pos
size: self.size
Widget:
pos_hint:{'x': 1, 'right': 0.04}
size_hint: 0.04,1
canvas:
Color:
rgb: [0.09,0.1372,0.2,1]
Rectangle:
pos: self.pos
size: self.size
Button:
text: "Home"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0.2
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.9, 'right': 0.35}
on_press:
Button:
text: "Area of a Triangle"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.75, 'right': 0.35}
on_press: root.manager.current = 'triscreen'
Button:
text: "LCM and HCF"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.6, 'right': 0.35}
on_press: root.manager.current = 'lcmscreen'
Button:
text: "Last Digit"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.45, 'right': 0.35}
on_press:
root.manager.current = 'ldscreen'
<LDScreen>:
Widget:
pos_hint:{'x': 0, 'right': 1}
size_hint: 2,2.1
canvas:
Color:
rgb: [0.09,0.1372,0.2,1]
Rectangle:
pos: self.pos
size: self.size
Widget:
pos_hint:{'x': 1, 'right': 0.35}
size_hint: 0.6,1
canvas:
Color:
rgb: [0.8,0.8,0.8,1]
Rectangle:
pos: self.pos
size: self.size
Widget:
pos_hint:{'x': 1, 'right': 0.04}
size_hint: 0.04,1
canvas:
Color:
rgb: [0.09,0.1372,0.2,1]
Rectangle:
pos: self.pos
size: self.size
Button:
text: "Home"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.9, 'right': 0.35}
on_press:
Button:
text: "Area of a Triangle"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.75, 'right': 0.35}
on_press:
Button:
text: "LCM and HCF"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.6, 'right': 0.35}
on_press:
Button:
text: "Last Digit"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0.2
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.45, 'right': 0.35}
on_press:
<LSMScreen>:
<TriScreen>:
id: triscreens
Widget:
pos_hint:{'x': 0, 'right': 1}
size_hint: 2,2.1
canvas:
Color:
rgb: [0.09,0.1372,0.2,1]
Rectangle:
pos: self.pos
size: self.size
Widget:
pos_hint:{'x': 1, 'right': 0.35}
size_hint: 0.6,1
canvas:
Color:
rgb: [0.8,0.8,0.8,1]
Rectangle:
pos: self.pos
size: self.size
Widget:
pos_hint:{'x': 1, 'right': 0.04}
size_hint: 0.04,1
canvas:
Color:
rgb: [0.09,0.1372,0.2,1]
Rectangle:
pos: self.pos
size: self.size
Button:
text: "Home"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.9, 'right': 0.35}
on_press:
Button:
text: "Area of a Triangle"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0.2
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.75, 'right': 0.35}
on_press:
Button:
text: "LCM and HCF"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.6, 'right': 0.35}
on_press:
Button:
text: "Last Digit"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.45, 'right': 0.35}
on_press:
Label:
text: "Area of a Triangle Calculator"
size_hint:
pos_hint: {"top": 1.35,"right":1.16}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
font_size: 35
Label:
text: "Start by entering the length of the sides"
size_hint:
pos_hint: {"top": 1.28,"right":1.1}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
font_size: 20
Image:
source: 'tridi.png'
keep_ratio: True
allow_stretch: False
opacity: 0.8
size_hint: 0.3, 0.4
pos_hint: {'top': 0.7, 'right': 0.99 }
TextInput:
id: sidea
text: "0"
size_hint: 0.2,0.08
pos_hint: {'top': 0.67, 'right': 0.68}
font_size: 26
TextInput:
id: sideb
text: "0"
size_hint: 0.2,0.08
pos_hint: {'top': 0.536, 'right': 0.68}
font_size: 26
TextInput:
id: sidec
text: "0"
size_hint: 0.2,0.08
pos_hint: {'top': 0.41, 'right': 0.68}
font_size: 26
Label:
id: lsidea
text: "a ="
size_hint: 0.2,0.08
font_size: 34
pos_hint: {'top': 0.675, 'right': 0.52}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
Label:
id: lsideb
text: "b ="
size_hint: 0.2,0.08
font_size: 34
pos_hint: {'top': 0.54, 'right': 0.52}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
Label:
id: lsidec
text: "c ="
size_hint: 0.2,0.08
font_size: 34
pos_hint: {'top': 0.42, 'right': 0.52}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
Label:
text: "The Area of the triangle is:"
size_hint: 0.18,0.18
font_size: 32
pos_hint: {'top': 0.32, 'right': 0.7}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
Label:
id: area
text: triscreens.calculate(sidea.text, sideb.text, sidec.text)
size_hint: 0.18,0.18
font_size: 32
pos_hint: {'top': 0.32, 'right': 1.01}
color: 0.8,0.8,0.8,1
background_color: 0.8,0.8,0.8,0
Button:
text: "ss"
color: 0.09,0.1372,0.2,1
background_color: 0.8,0.8,0.8,0
size_hint: 0.31,0.15
font_size: 28
pos_hint: {'top': 0.25, 'right': 0.6}
on_press: root.calc_area()
''')
class MainScreen(Screen):
pass
class LDScreen(Screen):
pass
class LCMScreen(Screen):
pass
class TriScreen(Screen):
def calculate(self, sidea, sideb, sidec):
self.sidea = sidea.text
self.sideb = sideb.text
self.sidec = sidec.text
if self.sidea == True and self.sideb == True and self.sidec == True:
try:
area.text = int(eval('sidea + sideb'))
except Exception:
area.text = "err"
sm = ScreenManager(transition=NoTransition())
sm.add_widget(MainScreen(name='main'))
sm.add_widget(LDScreen(name='ldscreen'))
sm.add_widget(LCMScreen(name='lcmscreen'))
sm.add_widget(TriScreen(name='triscreen'))
class SimpleKivy(App):
def build(self):
return sm
if __name__ == "__main__":
SimpleKivy().run()
如果正常工作，程序似乎只返回两边的和，但是我稍后会更改公式。我只需要帮助纠正错误即可。