import sys
from PyQt5 import QtWidgets
from PyQt5 import QtGui
from PyQt5 import QtCore


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)

    # MainWindow settings
    mainwindow = QtWidgets.QMainWindow()
    central_widget = QtWidgets.QWidget(mainwindow)
    central_layout = QtWidgets.QVBoxLayout(central_widget)
    mainwindow.setCentralWidget(central_widget)

    # content
    content = QtWidgets.QWidget()
    content_layout = QtWidgets.QGridLayout(content)
    scrollarea = QtWidgets.QScrollArea(central_widget)
    scrollarea.setWidget(content)
    # scrollarea.setWidgetResizable(True)
    central_layout.addWidget(scrollarea)

    # filling
    for i in range(0, 80, 2):
        text  = QtWidgets.QLabel("entry:")
        value = QtWidgets.QLineEdit()
        content_layout.addWidget(text, i/2, 0)
        content_layout.addWidget(value, i/2, 1)
    content.setMinimumSize(content.sizeHint())

    # sizing stuffs
    screen_max_size = app.desktop().availableGeometry(scrollarea).size() - QtCore.QSize(0, 60) # 60: for some reason the OS bar size isn't handled by default
    content_sizehint = content.sizeHint()

    overall_min_size = QtCore.QSize(min(screen_max_size.width(), content_sizehint.width()), min(screen_max_size.height(), content_sizehint.height()))
    overall_max_size = QtCore.QSize(max(screen_max_size.width(), content_sizehint.width()), max(screen_max_size.height(), content_sizehint.height()))

    scrollarea.setMinimumSize(overall_min_size)
    scrollarea.setMaximumSize(overall_max_size)

    mainwindow.show()

    sys.exit(app.exec_())