问题描述
我正在为我的程序做一个 tkinter GUI,我必须显示一些实时数据。我做了一个简单的程序(如下)来在一个简单的案例中演示我的问题。我实际上是在 for 循环的每次迭代中绘制一些数据,这样我就可以在程序仍在计算时观察数据。请注意,实际程序 si 计算速度稍慢,并且迭代次数更多。
现在我想添加 2 个按钮(一个是暂停程序,一个是继续)和一个标签(显示变量 k,以便我知道我的程序在哪里),但我无法做到。
我已经在这上面浪费了很多时间,所以如果有人有任何提示或解决方案,我很乐意看到。
import tkinter as tk
from matplotlib.backends.backend_tkagg import figureCanvasTkAgg,NavigationToolbar2Tk
import matplotlib.pyplot as plt
from matplotlib import style
def func_A(a,x):
import numpy
data_x = numpy.arange(0,x)
data_y = a * numpy.sin(data_x/5)
return data_x,data_y
a = 1
root = tk.Tk()
root.title("Graph")
root.geometry("800x400")
fig = plt.figure(figsize=(5,5),dpi=100)
canvas = figureCanvasTkAgg(fig,master=root) # A tk.DrawingArea.
canvas.draw()
canvas.get_tk_widget().pack(side=tk.TOP,fill=tk.BOTH,expand=1)
toolbar = NavigationToolbar2Tk(canvas,root)
toolbar.update()
canvas.get_tk_widget().pack(side=tk.TOP,expand=1)
plt.grid("both")
style.use("ggplot")
for k in range(0,100):
data_x,data_y = func_A(a,k)
print("iteration",k)
print("data_x",data_x)
print("data_y",data_y)
if k == 0:
ax1 = plt.subplot(111)
line1,= ax1.plot([0],[0])
else:
line1.set_xdata(data_x)
line1.set_ydata(data_y)
ax1.set_ylim([-1,1])
ax1.set_xlim([0,100])
plt.grid("both")
canvas.draw()
canvas.flush_events()
root.mainloop()
解决方法
添加暂停/恢复功能:
- 创建一个框架来保存进度标签和两个按钮:暂停和恢复
- 创建一个 tkinter
BooleanVar()
来存储暂停/恢复状态 - 在函数内移动更新绘图代码,例如
update_plot()
- 使用
.after()
替换 for 循环定期调用update_plot()
- 在
update_plot()
中,检查暂停/恢复状态以确定是否更新绘图
以下是根据您的代码修改的示例:
import tkinter as tk
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg,NavigationToolbar2Tk
import matplotlib.pyplot as plt
from matplotlib import style
import matplotlib
matplotlib.use("Agg")
root = tk.Tk()
root.title("Graph")
#root.geometry("800x400")
# progress label,pause and resume buttons
frame = tk.Frame(root)
frame.pack(fill="x",side=tk.TOP)
progress = tk.Label(frame)
progress.pack(side="left")
is_paused = tk.BooleanVar() # variable to hold the pause/resume state
tk.Button(frame,text="Pause",command=lambda: is_paused.set(True)).pack(side="right")
tk.Button(frame,text="Resume",command=lambda: is_paused.set(False)).pack(side="right")
# the plot
fig = plt.figure(figsize=(10,5),dpi=100)
canvas = FigureCanvasTkAgg(fig,master=root)
toolbar = NavigationToolbar2Tk(canvas,root)
canvas.get_tk_widget().pack(side=tk.TOP,fill=tk.BOTH,expand=1)
plt.grid("both")
style.use("ggplot")
a = 1
ax1 = plt.subplot(111)
line1,= ax1.plot([0],[0])
def func_A(a,x):
import numpy
data_x = numpy.arange(0,x)
data_y = a * numpy.sin(data_x/5)
return data_x,data_y
# function to update ploat
def update_plot(k=0):
if not is_paused.get():
progress["text"] = f"iteration: {k}"
data_x,data_y = func_A(a,k)
#print("iteration",k)
#print("data_x",data_x)
#print("data_y",data_y)
line1.set_xdata(data_x)
line1.set_ydata(data_y)
ax1.set_ylim([-1,1])
ax1.set_xlim([0,100])
plt.grid("both")
canvas.draw()
canvas.flush_events()
k += 1
if k <= 100:
# update plot again after 10ms. You can change the delay to whatever you want
root.after(10,update_plot,k)
update_plot() # start updating plot
root.mainloop()