如何使用pyqt4更新进度条

Question

Here it is sample program i want to update the my progress bar using with pyqt4.and i want to show th3 30% data saving and another 60% data processing.I am executing the my program it is aborting.Can any one please help me how to update the my progress bar.Thank you in advance. Given below is my code:

import sys
import time
from pyface.qt import QtGui, QtCore
global X,Y
X= 5
Y= 4

import threading
class SaveWorker(QtCore.QObject):
    progress_update = QtCore.Signal(int)
    def save_file(self):
        while True:
            MyCustomWidget().updateProgressBar()

class Dialog(QtGui.QDialog):
    def __init__(self, parent = None):
        super(Dialog, self).__init__(parent)
        self.setStyleSheet("QDialog {background-color:black; color:white }")
        self.label1 = QtGui.QLabel(
            text="Please Wait...",
            font=QtGui.QFont("Times", 20,weight=QtGui.QFont.Bold)
        )
        self.progress = QtGui.QProgressBar()
        self.box = QtGui.QVBoxLayout()
        self.label2 = QtGui.QLabel()
        vbox = QtGui.QVBoxLayout(self)
        vbox.addWidget(self.label1)
        vbox.addLayout(self.box)
        self.show_gif()
    def show_gif(self):
        self.progress = QtGui.QProgressBar()
        self.progress.setRange(0,100)

        self.box.addWidget(self.progress)
        self.show()
class MyCustomWidget(QtGui.QWidget):
    def __init__(self, parent=None):
        super(MyCustomWidget, self).__init__(parent)
        self.worker = SaveWorker()
        self.gif_dialog = Dialog()
        self.worker.progress_update.connect(self.gif_dialog.show_gif)
        thread = threading.Thread(target=self.worker.save_file)
        thread.daemon = True
        thread.start()
        self.progressPer = 0
        fileList = []

        processes = []
        _dataSavingPer = 30.0/(X*Y)
        for i in range(X*Y):
            name =  'file'+str(i+1) + ".txt"
            fileList.append(name)
            self.progressPer += _dataSavingPer
            self.updateProgressBar(self.progressPer)
            #updating the progress bar
        _dataProcessPer = 60.0/(X*Y)
        for file in fileList:
            process = 'fileProcess'+str(i+1) + ".txt"
            processes.append(process)
            self.progressPer += _dataProcessPer
            self.updateProgressBar(self.progressPer)
            #Updating the progressPer
            #how can i update these two values in to progressbar
    def updateProgressBar(self,value):
            self.gif_dialog.progress.setValue(value)
if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    window = MyCustomWidget()
    sys.exit(app.exec_())

Answer 1

I do not understand what you tried when writing the following:

class SaveWorker(QtCore.QObject):
    progress_update = QtCore.Signal(int)
    def save_file(self):
        while True:
            MyCustomWidget().updateProgressBar()

updateProgressBar requires a value what value are you going through?, on the other hand when using MyCustomWidget() you are creating an object different from the one shown, and no MyCustomWidget object should be created in another thread.

What you have to do is move the heavy task to the save_file method since it will be executed in another thread:

import sys
import threading
from pyface.qt import QtGui, QtCore

X, Y = 5, 4

class SaveWorker(QtCore.QObject):
    progressChanged = QtCore.Signal(int)

    def save_file(self):
        fileList = []
        processes = []
        _dataSavingPer = 30.0/(X*Y)
        progress = 0
        for i in range(X*Y):
            name =  'file'+str(i+1) + ".txt"
            fileList.append(name)
            progress += _dataSavingPer
            self.progressChanged.emit(progress)
        _dataProcessPer = 60.0/(X*Y)
        for file in fileList:
            process = 'fileProcess'+str(i+1) + ".txt"
            processes.append(process)
            progress += _dataProcessPer
            self.progressChanged.emit(progress)

class Dialog(QtGui.QDialog):
    def __init__(self, parent = None):
        super(Dialog, self).__init__(parent)
        self.setStyleSheet("QDialog {background-color:black; color:white }")
        self.label1 = QtGui.QLabel(
            text="Please Wait...",
            font=QtGui.QFont("Times", 20,weight=QtGui.QFont.Bold)
        )
        self.progress = QtGui.QProgressBar()
        self.box = QtGui.QVBoxLayout()
        self.label2 = QtGui.QLabel()
        vbox = QtGui.QVBoxLayout(self)
        vbox.addWidget(self.label1)
        vbox.addLayout(self.box)
        self.show_gif()

    def show_gif(self):
        self.progress = QtGui.QProgressBar()
        self.progress.setRange(0,100)
        self.box.addWidget(self.progress)
        self.show()

class MyCustomWidget(QtGui.QWidget):
    def __init__(self, parent=None):
        super(MyCustomWidget, self).__init__(parent)
        self.worker = SaveWorker()
        self.gif_dialog = Dialog()
        self.worker.progressChanged.connect(self.gif_dialog.progress.setValue)
        thread = threading.Thread(target=self.worker.save_file)
        thread.daemon = True
        thread.start()

if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    window = MyCustomWidget()
    sys.exit(app.exec_())