Why does markup fail and how to fix it?

Question

Python

from PyQt5 import QtWidgets, QtCore, QtGui
from PyQt5.Qt import *
import sys, os

class tagsGUI(object):
  def __init__(self):
    super(tagsGUI, self).__init__()
    self.title = 'tags'
    self.size = (850, 500, 25)
    self.start_win()

  def start_win(self):
    self.app = QtWidgets.QApplication(sys.argv)
    self.des = self.app.desktop().screenGeometry()
    self.win = QtWidgets.QWidget()
    self.win.setWindowTitle(self.title)
    self.win.setMinimumSize(self.size[0], self.size[1])
    self.win.move((self.des.width() - self.size[0]) // 2, self.size[2])

    self.pelt_window_box = QtWidgets.QVBoxLayout()
    self.pelt_window_box.setContentsMargins(0, 0, 0, -2)
    self.building_tags_window()
    self.win.setLayout(self.pelt_window_box)
    self.win.show()
    sys.exit(self.app.exec_())

  def building_tags_window(self):
    self.TAGS_WIDGET = dict()

    list_tags = list()
    for _ in range(20):list_tags.append(['2018_11.31.', 'тег', '#000000', 'описание'])
    	
    self.TAGS_WIDGET['layout_box'] = QtWidgets.QVBoxLayout()
    for i, tag in zip(range(len(list_tags)), list_tags):
      str_tags = 'str_tag_{}'.format(i)
      date = 'date_{}'.format(i)
      name_tag = 'name_tag_{}'.format(i)
      color_tag = 'color_tag_{}'.format(i)
      descrip = 'description_{}'.format(i)

      self.TAGS_WIDGET[str_tags] = QtWidgets.QHBoxLayout()
      self.TAGS_WIDGET[date] = QtWidgets.QLabel(tag[0])
      self.TAGS_WIDGET[name_tag] = QtWidgets.QLineEdit(tag[1])
      self.TAGS_WIDGET[color_tag] = QtWidgets.QLineEdit(tag[2])
      self.TAGS_WIDGET[descrip] = QtWidgets.QTextEdit(tag[3])

      self.TAGS_WIDGET[str_tags].addStretch(5)
      self.TAGS_WIDGET[str_tags].addWidget(self.TAGS_WIDGET[date], 0, QtCore.Qt.AlignLeft | QtCore.Qt.AlignTop)
      self.TAGS_WIDGET[str_tags].addWidget(self.TAGS_WIDGET[name_tag], 0, QtCore.Qt.AlignLeft | QtCore.Qt.AlignTop)
      self.TAGS_WIDGET[str_tags].addWidget(self.TAGS_WIDGET[color_tag], 0, QtCore.Qt.AlignLeft | QtCore.Qt.AlignTop)
      self.TAGS_WIDGET[str_tags].addWidget(self.TAGS_WIDGET[descrip], 100, QtCore.Qt.AlignRight | QtCore.Qt.AlignTop)
      self.TAGS_WIDGET[str_tags].addStretch(5)
      self.TAGS_WIDGET['layout_box'].addLayout(self.TAGS_WIDGET[str_tags])
    
    self.TAGS_WIDGET['widget'] = QtWidgets.QWidget()
    self.TAGS_WIDGET['widget'].setLayout(self.TAGS_WIDGET['layout_box'])

    self.TAGS_WIDGET['scroll_area'] = QtWidgets.QScrollArea()
    self.TAGS_WIDGET['scroll_area'].setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
    self.TAGS_WIDGET['scroll_area'].setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
    self.TAGS_WIDGET['scroll_area'].setWidget(self.TAGS_WIDGET['widget'])

    self.pelt_window_box.addWidget(self.TAGS_WIDGET['scroll_area'])

if __name__ == '__main__':
  tagsGUI()

By executing the code I get what is in the picture and this is somewhat not what I plan to see. My expectation is that the QTextEdit should stretch all the way to the scrollbar and all layout_box content should be centered on the screen with two addStretch . Meanwhile, all the content, ignoring the instructions, sticks and shrinks into the left corner.

Answer 1

You need to allow resizing of elements inside the scrollArea
Then it will float too, but
UPD layouts themselves will need to be configured
Remove alignment from self.TAGS_WIDGET[descrip], it moves the widget to the edge of the layout cell and uses the minimum widget sizes