Question

我正在尝试清空一个已满的进度条，模拟注射器的行为但由于某种原因无效。

使用按钮我调用mAspire，调用sEmpty（），然后调用sUp（），然后调用sStop（）然后调用sFull（），这样就会创建2个空的进度条，然后用函数＆填充它＃34;。步骤＆＃34;然后停止这些进度条，然后创建2个完整的进度条

使用按钮我调用mDispense，调用sFull（），然后是sDown（），然后调用sStop（）然后调用sEmpty（），这样就会创建2个完整进度条，然后用函数＆清空它们＃34;。步骤＆＃34;然后停止这些进度条，然后创建2个空的进度条

为什么不工作???????

帮助

import time
import serial
import sys
import os
import tkinter as tk
from tkinter import ttk
from tkinter import *
try:
    import Tkinter
    import ttk
except ImportError:
    import tkinter as Tkinter
    import tkinter.ttk as ttk

mGui = Tk()
mGui.title("try bar")
mGui.geometry('1250x650+10+10')

BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78,
                                 mode='determinate')
BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78,
                                 mode='determinate')
BarVolSyringe1.place(x=952,y=238)
BarVolSyringe2.place(x=930,y=238)

dir = -10
dirr = +10
def sStop():
    global BarVolSyringe1, BarVolSyringe2
    BarVolSyringe1.stop()
    BarVolSyringe2.stop()

def mAspire():
    global BarVolSyringe1, BarVolSyringe2
    sEmpty()
    mGui.after(1000, sUp)
    mGui.after(10000, sStop)
    mGui.after(10010, sFull)

def sUp():
    global BarVolSyringe1, BarVolSyringe2
    BarVolSyringe1.step(dirr)
    BarVolSyringe2.step(dirr)
    mGui.after(10, sUp)

def mDispense():
    global BarVolSyringe1, BarVolSyringe2
    sFull()
    mGui.after(1000, sDown)
    mGui.after(9999, sStop)
    mGui.after(10000, sEmpty)

def sDown():
    global BarVolSyringe1, BarVolSyringe2
    BarVolSyringe1.step(dir)
    BarVolSyringe2.step(dir)
    mGui.after(10, sDown)

def sFull():
    global BarVolSyringe1, BarVolSyringe2
    BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)
    BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)
    BarVolSyringe1.place(x=952,y=238)
    BarVolSyringe2.place(x=930,y=238)

def sEmpty():
    global BarVolSyringe1, BarVolSyringe2
    BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)
    BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)
    BarVolSyringe1.place(x=952,y=238)
    BarVolSyringe2.place(x=930,y=238)

mButtonAs = Button(mGui, text = "Aspire", command = mAspire,
                   fg = 'Black').place(x=110,y=360)
mButtonDis = Button(mGui, text = "Dispense", command = mDispense,
                   fg = 'Black').place(x=160,y=360)

没有错误的python消息，但是当我运行该函数时，它只是保持满，并且永远不会清空进度条。为什么这不起作用？

Answer 1

BarVolSyringe1在sDown中未定义，它是mDispense中的局部变量。在要共享的函数之外创建条：

BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)
BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)

def mDispense():
    BarVolSyringe1.place(x=952,y=238)
    BarVolSyringe2.place(x=930,y=238)
    sDown()
    mGui.after(5100, sEmpty)  # Schedule sEmpty only once, not in each sDown call

def sDown():
    BarVolSyringe1.step(dir)
    mGui.after(100, sDown)

def sEmpty():
    BarVolSyringe1.step(-100)
    BarVolSyringe2.step(-100)

修改

您不应该在功能中对BarVolSyringe1和BarVolSyringe2进行分配。它们是全局变量，并且使用BarVolSyringe1 = ...分配值不会重写全局变量，它只会创建一个具有相同名称的本地变量，它会影响全局变量直到函数结束。因此，您在函数之外创建的条形图保留在那里并使用sDown进行更新，但您没有看到这一点，因为在sFull中创建的条形图显示在它们上面。

要解决这个问题：

全局创建变量，仅使用BarVolSyringe1.step，BarVolSyringe2.update
等访问者方法
在分配函数中的全局变量之前输入global声明：

def sEmpty(): global BarVolSyringe1, BarVolSyringe2 BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0) BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)

将BarVolSyringe1和BarVolSyringe2置于某个可变对象的内部，例如某些dict，list，某个类的实例或mGui。然后，您将能够通过该对象访问和更新它们。

mGui.BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100) mGui.BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)

或

syringes = { 'BarVolSyringe1': ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100), 'BarVolSyringe2': ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100) } # Updating examples: syringes['BarVolSyringe1'].step(dir) syringes['BarVolSyringe1'] = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100),

或

syringes = [ ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100), ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100), ] # Updating examples: syringes[0].step(dir) syringes[1] = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100),

Answer 2

我想通了一个简单的方法，在python上试一试

import time
import serial
import sys
import os
import tkinter as tk
from tkinter import ttk
from tkinter import *
try:
  import Tkinter
  import ttk
except ImportError:
  import tkinter as Tkinter
  import tkinter.ttk as ttk
import time
mGui = Tk()
mGui.title("GUI")
mGui.geometry('120x450+100+100')
BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)
BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)
BarVolSyringe1.place(x=52,y=38)
BarVolSyringe2.place(x=30,y=38)
SFg=0
SFd=0
SyringeSize = 1000
Sy = SyringeSize/100
SVV_1 = 500
def mAspire():
 global SFg,SFd, BarVolSyringe2,BarVolSyringe1
 if SVV_1<=SyringeSize:
  while 0<=SFg<SVV_1:
    SFg=SFg+1
    SFd=SFd+1
    time.sleep(0.0001)
    BarVolSyringe1.step(1/Sy)
    BarVolSyringe2.step(1/Sy)
    mGui.update()
    print (SFg)
  else:
    mGui.update()
    SFg=0
    print (SFd)
  if (SFd >= SyringeSize):
    BarVolSyringe1.stop()
    BarVolSyringe2.stop()
    BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)
    BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 100)
    BarVolSyringe1.place(x=52,y=38)
    BarVolSyringe2.place(x=30,y=38)
    SFg=SVV_1
 else:
  messagebox.showerror("ERROR", "Please Select a valve")
mButtonAs = Button(mGui, text = "up", command = mAspire, fg = 'Black').place(x=10,y=60)

def dw():
  global SFg,SFd, BarVolSyringe2,BarVolSyringe1
  SFg=0
  while 0<=SFg<SVV_1:
    SFg=SFg+1
    SFd=SFd-1
    time.sleep(0.0001)
    BarVolSyringe1.step(-(1/Sy))
    BarVolSyringe2.step(-(1/Sy))
    mGui.update()
    print (SFg)
  else:
    mGui.update()
    SFg=0
    print (SFd)
  if (SFd == 0):
    BarVolSyringe1.stop()
    BarVolSyringe2.stop()
    BarVolSyringe1 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)
    BarVolSyringe2 = ttk.Progressbar(mGui, orient='vertical', length=78, mode='determinate', value = 0)
    BarVolSyringe1.place(x=52,y=38)
    BarVolSyringe2.place(x=30,y=38)

mButtonAs = Button(mGui, text = "dw", command = dw, fg = 'Black').place(x=10,y=90)

Answer 3

尝试使用sDown。

def sDown():
    BarVolSyringe1.step(dir)
    BarVolSyringe1.update ()  # Added this.
    mGui.after(1000, sDown)
    mGui.after(5100, sEmpty)

Progressbar不会降低python 3.4 tkinter

3 个答案: