問題描述

我可以使用 Kivy 和 Matplotlib 很好地生成 2D 曲面圖.我正在嘗試在單擊按鈕時更新 Z 值.這如何實現?

I can generate a 2D surface plot very nicely with Kivy and Matplotlib. I am trying to update the Z values on a button click. How may this be accomplished?

我注意到我可以發出一個 plt.clf() 來清除繪圖，但是執行 plt.gcf() 來顯示當前繪圖不起作用.

I noticed that I can issue a plt.clf() which will clear the plot but doing the plt.gcf() to display the current plot doesn't work.

任何建議將不勝感激.

import matplotlib
matplotlib.use('module://kivy.garden.matplotlib.backend_kivy')
from matplotlib.figure import Figure
from numpy import arange, sin, pi
from kivy.app import App

import numpy as np
from matplotlib.mlab import griddata
from kivy.garden.matplotlib.backend_kivy import FigureCanvas,
                                                NavigationToolbar2Kivy

# from backend_kivy import FigureCanvasKivy as FigureCanvas

from kivy.uix.floatlayout import FloatLayout
from kivy.uix.boxlayout import BoxLayout
from matplotlib.transforms import Bbox
from kivy.uix.button import Button
from kivy.graphics import Color, Line, Rectangle

import matplotlib.pyplot as plt
from matplotlib import cm
from mpl_toolkits.mplot3d import Axes3D

fig, ax = plt.subplots()

X = np.arange(-508, 510, 203.2)
Y = np.arange(-508, 510, 203.2)
X, Y = np.meshgrid(X, Y)

Z = np.random.rand(6, 6)

plt.contourf(X, Y, Z, 100, zdir='z', offset=1.0, cmap=cm.hot)
plt.colorbar()

ax.set_ylabel('Y [mm]')
ax.set_title('NAILS surface')
ax.set_xlabel('X [mm]')

canvas = fig.canvas


def callback(instance):


    fig, ax = plt.subplots()

    X = np.arange(-508, 510, 203.2)
    Y = np.arange(-508, 510, 203.2)
    X, Y = np.meshgrid(X, Y)

    Z = np.random.rand(6, 6)

    plt.contourf(X, Y, Z, 100, zdir='z', offset=1.0, cmap=cm.hot)
    plt.colorbar()

    ax.set_ylabel('Y [mm]')
    ax.set_title('NAILS surface')
    ax.set_xlabel('X [mm]')

    canvas = fig.canvas
    canvas.draw()


class MatplotlibTest(App):
    title = 'Matplotlib Test'

    def build(self):
        fl = BoxLayout(orientation="vertical")
        a = Button(text="press me", height=40, size_hint_y=None)
        a.bind(on_press=callback)

        fl.add_widget(canvas)
        fl.add_widget(a)
        return fl

if __name__ == '__main__':
    MatplotlibTest().run()

推薦答案

代碼第 45 行:

fig, ax = plt.subplots()

創建一個新圖形，從而創建一個新畫布.此畫布從未添加到 BoxLayout 中，因此從未顯示.重新使用舊畫布可能是一個更好的主意.把回調函數改成這樣:

creates a new figure and hence a new canvas. This canvas is never added to the BoxLayout and hence never shown. It's probably a better idea to re-use the old canvas. Change the callback function to this:

def callback(instance):
    # Clear the existing figure and re-use it
    plt.clf()

    X = np.arange(-508, 510, 203.2)
    Y = np.arange(-508, 510, 203.2)
    X, Y = np.meshgrid(X, Y)

    Z = np.random.rand(6, 6)

    plt.contourf(X, Y, Z, 100, zdir='z', offset=1.0, cmap=cm.hot)
    plt.colorbar()

    ax.set_ylabel('Y [mm]')
    ax.set_title('NAILS surface')
    ax.set_xlabel('X [mm]')

    canvas.draw_idle()

這篇關于Kivy 和 Matplotlib 試圖更新按鈕回調的情節的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！