Question

我有代码片段来生成底图，以及GUI（非常粗略）的启动。但是，我找不到那个＆＃34; one-liner＆＃34;将允许我将地图显示为GUI中的图形。代码片段如下;理想情况下，我想要做一些事情：

＆＃39;底图的图像＆＃39;重新审视sin(2*pi*t)
我真的很想代码在图形上记录（像素）位置，如果我点击显示的图表（希望你可以点击地图上的任何地方，脚本会记录纬度和你点击的经度。）

关于第1步，我尝试过设置图形变量f等于底图;这完全杀死了GUI部分，只是在另一个窗口中显示了地图的图像。

我试图通过尝试实现我在stackexchange上找到的几个例程来解决＃2问题，但从未让它完全运行。

底图：

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap

## User-chosen datapoint
#lons = [10]; lats = [20];

# Define map projection
m = Basemap(projection='cyl',llcrnrlat=-90,urcrnrlat=90,\
            llcrnrlon=-180,urcrnrlon=180,resolution='c')
m.drawcoastlines()

粗糙的GUI：

import matplotlib
matplotlib.use('TkAgg')

from numpy import arange, sin, pi
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
# implement the default mpl key bindings
from matplotlib.backend_bases import key_press_handler

from Tkinter import *
from PIL import Image
import numpy as np
import matplotlib.pyplot as plt

from PIL import Image
from mpl_toolkits.basemap import Basemap

from matplotlib.figure import Figure

import sys
if sys.version_info[0] < 3:
    import Tkinter as Tk
else:
    import tkinter as Tk

root = Tk.Tk()
root.wm_title("Embedding in TK")

f = Figure(figsize=(5, 4), dpi=100)
a = f.add_subplot(111)
t = arange(0.0, 3.0, 0.01)
s = sin(2*pi*t)

a.plot(t, s)

# a tk.DrawingArea
canvas = FigureCanvasTkAgg(f, master=root)
canvas.show()
canvas.get_tk_widget().pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

toolbar = NavigationToolbar2TkAgg(canvas, root)
toolbar.update()
canvas._tkcanvas.pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

def on_key_event(event):
    print('you pressed %s' % event.key)
    key_press_handler(event, canvas, toolbar)

canvas.mpl_connect('key_press_event', on_key_event)

def _quit():
    root.quit()     # stops mainloop
    root.destroy()  # this is necessary on Windows to prevent
                    # Fatal Python Error: PyEval_RestoreThread: NULL tstate
button = Tk.Button(master=root, text='Quit', command=_quit)
button.pack(side=Tk.BOTTOM)

Tk.mainloop()

Answer 1

一种简单的技术是定义on_click函数，显示图像，然后覆盖该图像。尽管图像发生了变化，on_click功能仍会读取鼠标点击位置。

下面是一个示例代码，证明如下所示：

import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap

def on_click(event):
    if event.inaxes is not None:
        print event.xdata, event.ydata
    else:
        print 'Clicked ouside axes bounds but inside plot window'

fig, ax = plt.subplots()
fig.canvas.callbacks.connect('button_press_event', on_click)
plt.show()

#Define map projection
m = Basemap(projection='cyl', llcrnrlat=-90, urcrnrlat=90,
            llcrnrlon=-180, urcrnrlon=180, resolution='c')
m.drawcoastlines()

Answer 2

如何将底图绘制到Tkinter中的问题实际上尚未得到解答。因此，我们的想法是在图中创建一个轴ax并将底图添加到轴中。这是通过ax参数

完成的

m = Basemap(..., ax=ax)

然后以通常的方式将该图添加到画布中;下面是一个完整的例子。

from mpl_toolkits.basemap import Basemap
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.figure import Figure

import sys
if sys.version_info[0] < 3:
    import Tkinter as Tk
else:
    import tkinter as Tk

root = Tk.Tk()
root.wm_title("Embedding in TK")

fig = Figure(figsize=(5, 4), dpi=100)
ax = fig.add_subplot(111)

m = Basemap(projection='cyl',llcrnrlat=-90,urcrnrlat=90,\
            llcrnrlon=-180,urcrnrlon=180,resolution='c', ax=ax)
m.drawcoastlines()

# a tk.DrawingArea
canvas = FigureCanvasTkAgg(fig, master=root)
canvas.show()
canvas.get_tk_widget().pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

toolbar = NavigationToolbar2TkAgg(canvas, root)
toolbar.update()
canvas._tkcanvas.pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

def _quit():
    root.quit()     # stops mainloop
    root.destroy()  # this is necessary on Windows to prevent
                    # Fatal Python Error: PyEval_RestoreThread: NULL tstate
button = Tk.Button(master=root, text='Quit', command=_quit)
button.pack(side=Tk.BOTTOM)

Tk.mainloop()

注意：在较新版本的matplotlib中，您应使用NavigationToolbar2Tk代替NavigationToolbar2TkAgg。

使用底图作为Python GUI中的图形

2 个答案: