基维！在多个屏幕上加载matplot图

Question

我正在尝试从一个屏幕从文件选择器加载图像，并尝试在另一个屏幕上显示该图像的matplotlib图形 我使用了Kivy_matplotlib库 这是密码

import numpy as np
import matplotlib.widgets as widgets
import PIL
import matplotlib as mpl
from matplotlib import pyplot as plt
from PIL import Image
from kivy.app import App
from kivy.lang import Builder
from kivy_matplotlib import MatplotFigure, MatplotNavToolbar
from kivy.uix.screenmanager import ScreenManager, Screen

kv = """
<ScreenTwo>:
    id:sc1
    BoxLayout:
        FileChooserListView:
            id: filechooser
            on_selection: my_widget.selected(filechooser.selection)
        Button:
            text: "Go to Screen 1"
            on_press:
                root.manager.transition.direction = 'right'
                root.manager.current = 'screen_one'

<ScreenOne>
    BoxLayout:
        orientation: 'vertical'
        Button:
            text:"Choose File"
            on_press:
                root.manager.transition.direction = 'right'
                root.manager.current = 'screen_two'
        MatplotFigure:
            id: figure_wgt
            size_hint: 1, 0.9
        MatplotNavToolbar:
            id: navbar_wgt
            size_hint: 1, 0.1
            figure_widget: figure_wgt
"""

class ScreenOne(Screen):
    pass


class ScreenTwo(Screen):
    pass


# The ScreenManager controls moving between screens
screen_manager = ScreenManager()

# Add the screens to the manager and then supply a name
# that is used to switch screens
screen_manager.add_widget(ScreenOne(name="screen_one"))
screen_manager.add_widget(ScreenTwo(name="screen_two"))

class testApp(App):
    title = "Test Matplotlib"

    def build(self):

        # Matplotlib stuff, figure and plot
        fig = mpl.figure.Figure(figsize=(2, 2))

        def onselect(eclick, erelease):
            if eclick.ydata>erelease.ydata:
                eclick.ydata,erelease.ydata=erelease.ydata,eclick.ydata
            if eclick.xdata>erelease.xdata:
                eclick.xdata,erelease.xdata=erelease.xdata,eclick.xdata
            ax.set_ylim(erelease.ydata,eclick.ydata)
            ax.set_xlim(eclick.xdata,erelease.xdata)
            fig.canvas.draw()

        fig = plt.figure()
        ax = fig.add_subplot(111)
        filename="phase.jpg"
        im = Image.open(filename)
        arr = np.asarray(im)
        plt_image=plt.imshow(arr)
        rs=widgets.RectangleSelector(
            ax, onselect, drawtype='box',
            rectprops = dict(facecolor='red', edgecolor = 'black', alpha=0.5, fill=True))
        #plt.show()
        print(arr)

        # Kivy stuff
        root = Builder.load_string(kv)
        figure_wgt = ScreenOne.ids['figure_wgt']  # MatplotFigure
        figure_wgt.figure = fig

        return screen_manager

#testApp().run()

sample_app = testApp()
sample_app.run()

当我得到以下信息时，我被卡住了 回溯

^{pr2}$

需要帮助吗 提前谢谢

Answer 1

您需要重新排序代码执行流程。在添加小部件之前，必须在语言生成器中插入字符串。在

kv = """
<ScreenTwo>:
    id:sc1
    BoxLayout:
        FileChooserListView:
            id: filechooser
            on_selection: my_widget.selected(filechooser.selection)
        Button:
            text: "Go to Screen 1"
            on_press:
                root.manager.transition.direction = 'right'
                root.manager.current = 'screen_one'

<ScreenOne>:
    BoxLayout:
        orientation: 'vertical'
        Button:
            text:"Choose File"
            on_press:
                root.manager.transition.direction = 'right'
                root.manager.current = 'screen_two'
        MatplotFigure:
            id: figure_wgt
            size_hint: 1, 0.9
        MatplotNavToolbar:
            id: navbar_wgt
            size_hint: 1, 0.1
            figure_widget: figure_wgt
"""
# Insert string into Language builder.
Builder.load_string(kv)

class ScreenOne(Screen):
    pass

class ScreenTwo(Screen):
    pass

# The ScreenManager controls moving between screens
screen_manager = ScreenManager()
screen_manager.add_widget(ScreenOne(name="screen_one"))
screen_manager.add_widget(ScreenTwo(name="screen_two"))

class testApp(App):
    title = "Test Matplotlib"

    def build(self):

        # ....

        # get first screen and update figure

        screen_one = screen_manager.get_screen('screen_one')

        screen_one.ids['figure_wgt'].figure = fig

        return screen_manager


sample_app = testApp()
sample_app.run()