Question

我正在尝试使用Python并使用Kivy作为GUI创建工具。当用户运行该工具时，我希望显示进度条。我通过使用Kivy屏幕实现了这一目标。我有一个主菜单屏幕，一个文件选择器弹出窗口和一个进度栏。

屏幕工作正常，但是进度条（屏幕）仅在方法的其余部分完成后才从主菜单更改。即使我告诉屏幕要更改。当屏幕最终改变时，该工具已经完成运行，因此无法达到进度条的要求。

我似乎无法解决这个问题。我尝试使用弹出窗口，但遇到了同样的问题。通过插入一些断点并使用调试器，我可以看到屏幕管理器已经实现了更改，但是直到程序结束才更改屏幕。

main.py

#When run button is pressed the run method is called
import sys
import time

from kivy.app import App
from kivy.lang import Builder
from kivy.properties import ObjectProperty
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.popup import Popup
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.properties import ObjectProperty
from kivy.uix.popup import Popup
from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
import os
from kivy.uix.screenmanager import ScreenManager, Screen



class MainScreen(Screen):
    loadfile = ObjectProperty(None)
    text_input = ObjectProperty(None)

    # Dissmiss Popup aka cancel button
    def dismiss_popup(self):
        self._popup.dismiss()

    # File Browser
    def show_load(self):
        content = LoadDialog(load=self.load, cancel=self.dismiss_popup)
        self._popup = Popup(title="Select Disk Image", content=content, size_hint=(0.9, 0.9))
        self._popup.open()

    # Select file function
    def load(self, path, filename):
        with open(os.path.join(path, filename[0])):
            global diskimage
            diskimage = filename[0]

    # When the run button is clicked
    # Makes sure they have to select a file before pressing run
    def run(self):
        if diskimage is None:
            "Please Select a Disk Image"
        else:
            print("Initialising")
            # calling BulkExrtaor class
            print("screen currently set to:", self.manager.current)

            self.manager.current = 'progressbar'

            print("screen currently set to:", self.manager.current)

            BulkExtractor().bulkextractor_run()
            #p1.start()
            print(self.manager.current)
            print("changed?")
    def startBE(self):
        BulkExtractor().bulkextractor_run()


class AnotherScreen(Screen):

    pass


class ScreenManagement(ScreenManager):
    pass

class GUI_RUN(App):

    def build(self):
        return presentation

class BulkExtractor(MainScreen):

    #Bulk Extractor run method
    def bulkextractor_run(self):
         print("File Path to file", "\"" + diskimage + "\"")

         #Runs Bulk Extractor
         #command im trying to run
         # os.system("%Programdata%\\bulk_extractor64.exe -o output ""\"" + diskimage + "\"")

        #Using sleep as a test instead of trying to run the actual command above
         print("Still hasn't changed")
         time.sleep(20)
         print("Still hasn't changed")

         print("Program Finished")

class Progressbar(ScreenManager):
    pass

class LoadDialog(FloatLayout):
    load = ObjectProperty(None)
    cancel = ObjectProperty(None)

presentation = Builder.load_file("main.kv")

if __name__ == "__main__":
    GUI_RUN().run()

Main.kv

ScreenManagement:
    MainScreen:
    AnotherScreen:

<MainScreen>:
    name: 'main'
    FloatLayout:
        Label:
            font_size: 50
            size_hint: 0.3, 0.2
            text: "FD"
            pos_hint: {"right": 0.65,'top':1}

        Button:
            font_size: 25
            size_hint: 0.3, 0.2
            text: "Select Disk Image"
            pos_hint: {"right": 0.65,'top':0.5}
            on_press: root.show_load()

        Button:
            font_size: 25
            size_hint: 0.3, 0.2
            text: "Run"
            pos_hint: {"right": 0.65,'top':0.3}
            on_press: root.run()

<LoadDialog>:
    BoxLayout:
        size: root.size
        pos: root.pos
        orientation: "vertical"
        FileChooserIconView:
            id: filechooser
            path: "C:/"

        BoxLayout:
            size_hint_y: None
            height: 30
            Button:
                text: "Cancel"
                on_release: root.cancel()

            Button:
                text: "Select"
                on_press: root.load(filechooser.path, filechooser.selection)
                on_release: root.cancel()

<AnotherScreen>:
    name: 'progressbar'
    Label:
        text: 'Progress: {}%'.format(int(pb.value))
        size_hint_y: None
        pos: 10, 400
        font_size: 30
    ProgressBar:
        id: pb
        min: -100
        max: 100
        value: 0
        size_hint: 0.5 , 1.0
        width: 200
        pos : 200, 70

    Button:
        on_release: app.root.current = 'main'
        text: 'Cancel'
        size_hint_x: .3
        size_hint_y: .1
        pos: 290, 190
        font_size:

处理完类别/方法后，屏幕将发生变化。...

有人可以告诉我我在做什么错吗？

要对此进行测试，请运行代码并选择系统上的任何文件，然后单击“运行”。

Answer 1

您有一个普遍的问题，就是您的bulkextractor_run()方法在主线程上运行，从而使主线程处于繁忙状态，因此它无法更新任何GUI元素。为了使其正常工作，请在其他线程中运行该方法：

def run(self):
    if diskimage is None:
        "Please Select a Disk Image"
    else:
        print("Initialising")
        # calling BulkExrtaor class
        print("screen currently set to:", self.manager.current)

        self.manager.current = 'progressbar'

        print("screen currently set to:", self.manager.current)

        Thread(target=BulkExtractor().bulkextractor_run).start()

        print(self.manager.current)
        print("changed?")

然后，在您的bulkextractor_run()方法中，您可能需要使用ProgressBar在主线程上进行Clock.schedule_once()更新，如下所示：

class BulkExtractor(MainScreen):


    #Bulk Extractor run method
    def bulkextractor_run(self):
         print("File Path to file", "\"" + diskimage + "\"")

         #Runs Bulk Extractor
         #command im trying to run
         # os.system("%Programdata%\\bulk_extractor64.exe -o output ""\"" + diskimage + "\"")

        #Using sleep as a test instead of trying to run the actual command above
         for i in range(101):
             time.sleep(0.1)
             Clock.schedule_once(partial(self.update_progressBar, i))

         print("Program Finished")

    def update_progressBar(self, val, dt):
        presentation.get_screen('progressbar').ids.pb.value = val

奇异果|直到程序结束，屏幕才会改变

1 个答案: