20170904 （第4课）树莓派PYPI- python-tk

button 教程
http://blog.csdn.net/jcodeer/article/details/1811298
滚动条教程
http://blog.csdn.net/jcodeer/article/details/1811313

最基本的TK按键程序：

from tkinter import *

#定义Button的回调函数
def helloButton():
    print("hello button")

root = Tk()
Button(root,text = "hello Button",command = helloButton).pack()
#通过command属性来指定Button的回调函数
#Button(root,text = "Hello Button",command = helloButton).pack()
root.mainloop()

from tkinter import *

#定义Button的回调函数

def helloButton():

print("hello button")

root = Tk()

Button(root,text = "hello Button",command = helloButton).pack()

#通过command属性来指定Button的回调函数

#Button(root,text = "Hello Button",command = helloButton).pack()

root.mainloop()

#例程1：按键控制LED灯亮度累加
from gpiozero import PWMLED,Button
from signal import pause

led = PWMLED(17)
button = Button(2)
led.value=0

def ledvalplus() :
if led.value &gt; =0.9:#由于浮点数的关系，此数值需要为0.9
led.value=0
else :
led.value+=0.1

while True:
button.wait_for_press()
ledvalplus()
button.wait_for_release()

#例程1：按键控制LED灯亮度累加

from gpiozero import PWMLED,Button

from signal import pause

led = PWMLED(17)

button = Button(2)

led.value=0

def ledvalplus() :

if led.value > =0.9:#由于浮点数的关系，此数值需要为0.9

led.value=0

else :

led.value+=0.1

while True:

button.wait_for_press()

ledvalplus()

button.wait_for_release()

#例程2：tk按键控制LED灯
from tkinter import *
from gpiozero import LED

led = LED(17)

#定义Button的回调函数
def helloButton():
print ('hello button')
led.toggle()#led状态翻转
root = Tk()
#通过command属性来指定Button的回调函数
Button(root,text = 'LED Button',command = helloButton).pack()
root.mainloop()#TK的主程序循环

#例程2：tk按键控制LED灯

from tkinter import *

from gpiozero import LED

led = LED(17)

#定义Button的回调函数

def helloButton():

print ('hello button')

led.toggle()#led状态翻转

root = Tk()

#通过command属性来指定Button的回调函数

Button(root,text = 'LED Button',command = helloButton).pack()

root.mainloop()#TK的主程序循环

#例程3：滚动条控制LED灯亮度
from gpiozero import PWMLED
from tkinter import *

led = PWMLED(17)

def ledset(text):
led.value = float(text)

root = Tk()
Scale(root,
from_ = 0.0, #设置最大值
to = 1.0, #设置最小值
resolution = 0.01, #设置步距值
orient = HORIZONTAL, #设置水平方向
command = ledset #设置回调函数

).pack()
root.mainloop()