python3.x+pyqt5实现主窗口状态栏里（嵌入）显示进度条

1、代码1：

（1）进度条等显示在主窗口状态栏的右端，代码如下：

from PyQt5.QtWidgets import QMainWindow, QProgressBar, QApplication, QLabel
import sys


class SampleBar(QMainWindow):
    """Main Application"""
    def __init__(self, parent = None):
        print('Starting the main Application')
        super(SampleBar, self).__init__(parent)
        self.initUI()

    def initUI(self):
        # Pre Params:
        self.setMinimumSize(800, 600)

        # File Menus & Status Bar:
        self.statusBar().showMessage('准备中...')
        self.progressBar = QProgressBar()
        self.label = QLabel()
        self.label2 = QLabel()
        self.label.setText("正在计算： ")
        self.label2.setText("正在计算： ")

        self.statusBar().addPermanentWidget(self.label)
        self.statusBar().addPermanentWidget(self.label2)
        self.statusBar().addPermanentWidget(self.progressBar)
        # self.statusBar().addWidget(self.progressBar)

        # This is