Kivy！ 在多個屏幕上加載Matplot圖形

Question

我正在嘗試從屏幕的文件選擇器加載圖像並嘗試在其他屏幕上顯示圖像的matplotlib圖，為此我使用了Kivy_matplotlib庫，這里是代碼

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()

我遇到以下回溯時被卡住了

/home/naveen/Environments/aagnaa/bin/python "/home/naveen/Py files/tut/select and crop2 (copy).py"
[INFO              ] [Logger      ] Record log in /home/naveen/.kivy/logs/kivy_17-06-01_150.txt
[INFO              ] [Kivy        ] v1.9.1
[INFO              ] [Python      ] v3.5.2 (default, Nov 17 2016, 17:05:23) 
[GCC 5.4.0 20160609]
[INFO              ] [Factory     ] 179 symbols loaded
[INFO              ] [Image       ] Providers: img_tex, img_dds, img_gif, img_sdl2, img_pil (img_ffpyplayer ignored)
[INFO              ] [OSC         ] using <multiprocessing> for socket
[INFO              ] [Window      ] Provider: sdl2(['window_egl_rpi'] ignored)
[INFO              ] [GL          ] OpenGL version <b'2.1 Mesa 12.0.6'>
[INFO              ] [GL          ] OpenGL vendor <b'Intel Open Source Technology Center'>
[INFO              ] [GL          ] OpenGL renderer <b'Mesa DRI Intel(R) Ironlake Mobile '>
[INFO              ] [GL          ] OpenGL parsed version: 2, 1
[INFO              ] [GL          ] Shading version <b'1.20'>
[INFO              ] [GL          ] Texture max size <8192>
[INFO              ] [GL          ] Texture max units <16>
[INFO              ] [Window      ] auto add sdl2 input provider
[INFO              ] [Window      ] virtual keyboard allowed, single mode, docked

 Traceback (most recent call last):
   File "/home/naveen/Py files/tut/select and crop2 (copy).py", line 97, in <module>
     sample_app.run()
   File "/usr/lib/python3/dist-packages/kivy/app.py", line 802, in run
     root = self.build()
   File "/home/naveen/Py files/tut/select and crop2 (copy).py", line 89, in build
     figure_wgt = ScreenOne.ids['figure_wgt']  # MatplotFigure
 TypeError: 'kivy.properties.DictProperty' object is not subscriptable

Process finished with exit code 1

需要幫助預先感謝

Answer 1

您需要重新排序代碼執行流程。 您必須在添加小部件之前將字符串插入“語言生成器”。

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()