[FIXED] How to make QLabel subwidgets inside a QScrollArea use wordwrap instead of expanding the container widget?

Issue

My code has two files. One is the "main" file that uses a fixed size QFrame instead of the standard window frame. The second is also a subclassed QWidget for adding to the QScrollArea in the main widget.

I want the QFrame of the subwidget to be fixed and the label to actually use the wordwrap property instead of just making it longer to fit and screwing up the whole QScrollArea scrolling area. I have tried using QSizePolicy for the container_widget and QFrame of the subwidget. A minimal reproducible example is as follows.

main_window.py

import sys

from PyQt5 import QtWidgets as qtw
from PyQt5 import QtCore as qtc
from PyQt5 import QtGui as qtg

from subwidget import SubWidget


class Window(qtw.QWidget):
    def __init__(self):
        super().__init__()
        
        # Configure Window
        self.setWindowFlags(qtc.Qt.FramelessWindowHint)
        self.setAttribute(qtc.Qt.WA_TranslucentBackground)
        self.setFixedSize(350, 450)
        
        # Init Methods
        self.setupUI()
        self.refresh_entries()
        
        self.show()
    
    def setupUI(self):
        # Main Layout/Frame
        self.main_layout = qtw.QHBoxLayout()
        self.main_frame = qtw.QFrame()
        self.main_frame_layout = qtw.QVBoxLayout()
        # Set Layouts
        self.setLayout(self.main_layout)
        self.main_layout.addWidget(self.main_frame)
        self.main_frame.setLayout(self.main_frame_layout)
        # Configure QFrame
        self.main_frame.setContentsMargins(10, 10, 10, 10)
        self.main_frame.setObjectName("main_frame")  
        self.main_frame.setStyleSheet("""
                                      border: None;
                                      border-radius: 10px;
                                      background: #1E1E1E;
                                      """)      
        # Secondary Layout/Widget
        self.main_scroll_area = qtw.QScrollArea()
        self.container_widget = qtw.QWidget()
        self.container_layout = qtw.QVBoxLayout()
        self.main_scroll_area.setObjectName("main_scroll_area")                
        self.main_scroll_area.setWidgetResizable(True)
        self.main_scroll_area.setVerticalScrollBarPolicy(qtc.Qt.ScrollBarPolicy.ScrollBarAlwaysOff)
        self.main_scroll_area.setHorizontalScrollBarPolicy(qtc.Qt.ScrollBarPolicy.ScrollBarAlwaysOff)
        self.main_scroll_area.setWidget(self.container_widget)
        self.container_widget.setLayout(self.container_layout)
        self.container_widget.setObjectName("container_widget")
        # Widget -> Layout
        self.main_frame_layout.addWidget(self.main_scroll_area, 0, qtc.Qt.AlignmentFlag.AlignHCenter | qtc.Qt.AlignmentFlag.AlignCenter)
    
    def refresh_entries(self):
        self.clear_entries()
                
        for i in range(5):
            self.container_layout.addWidget(SubWidget(i ** i ** i, i))

    def clear_entries(self):
        for i in reversed(range(self.container_layout.count())):
            try:
                widget = self.container_layout.itemAt(i).widget()
                widget.setParent(None)
            except Exception:
                pass
        
        
if __name__ == "__main__":
    app = qtw.QApplication(sys.argv)
    win = Window()
    sys.exit(app.exec())

and subwidget.py

from PyQt5 import QtWidgets as qtw
from PyQt5 import QtCore as qtc
from PyQt5 import QtGui as qtg


class SubWidget(qtw.QWidget):
    def __init__(self, name, index):
        super().__init__()
        
        # Variables
        self.name = str(name)
        self.index = index    
           
        # Init Methods
        self.setupUI()        
        
        self.show()
    
    def setupUI(self):
        # Main Layout/Frame
        self.main_layout = qtw.QHBoxLayout()
        self.main_frame = qtw.QFrame()
        self.main_frame_layout = qtw.QVBoxLayout()
        # Set Layouts
        self.setLayout(self.main_layout)
        self.main_layout.addWidget(self.main_frame)
        self.main_frame.setLayout(self.main_frame_layout)
        # Configure QFrame
        self.main_frame.setContentsMargins(5, 5, 5, 5)
        self.main_frame.setStyleSheet("""
                                      border: None;
                                      border-radius: 5px;
                                      background: #000000;
                                      """)               
        # Secondary Layout/Widget        
        self.name_lbl = qtw.QLabel()
        # Configure Seondary Widgets                
        self.name_lbl.setText(self.name)      
        self.name_lbl.setStyleSheet("""
                                    color: #FFFFFF;
                                    """)   
        self.name_lbl.setWordWrap(True)  # https://stackoverflow.com/questions/49838817/how-to-resize-qlabels-to-fit-contents-in-qscrollarea        
        # Widget -> Layout
        self.main_frame_layout.addWidget(self.name_lbl, 0, qtc.Qt.AlignmentFlag.AlignHCenter | qtc.Qt.AlignmentFlag.AlignCenter)

This is a visual of the resulting window/frame.

Solution

A Wrapable Anywhere QLabel

My way to achieve this to subclass QLabel and and implement the paintEvent, where you can set the text alignment to TextWrapAnywhere when you drawItemText.

Here is a sample code.

from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPainter
from PyQt5.QtWidgets import QApplication, QLabel, QMainWindow, QStyleOption, QVBoxLayout, QWidget, QStyle

class SuperQLabel(QLabel):
    def __init__(self, *args, **kwargs):
        super(SuperQLabel, self).__init__(*args, **kwargs)

        self.textalignment = Qt.AlignLeft | Qt.TextWrapAnywhere
        self.isTextLabel = True
        self.align = None

    def paintEvent(self, event):

        opt = QStyleOption()
        opt.initFrom(self)
        painter = QPainter(self)

        self.style().drawPrimitive(QStyle.PE_Widget, opt, painter, self)

        self.style().drawItemText(painter, self.rect(),
                                  self.textalignment, self.palette(), True, self.text())


class MainWindow(QMainWindow):
    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)

        self.setFixedSize(100, 200)

        self.label = QLabel()
        self.label.setWordWrap(True)
        self.label.setText("1111111111111111111111111111")

        self.slabel = SuperQLabel()
        self.slabel.setText("111111111111111111111111111")

        self.centralwidget = QWidget()
        self.setCentralWidget(self.centralwidget)

        self.mainlayout = QVBoxLayout()
        self.mainlayout.addWidget(self.label)
        self.mainlayout.addWidget(self.slabel)

        self.centralwidget.setLayout(self.mainlayout)


if __name__ == "__main__":
    import sys
    app = QApplication(sys.argv)
    w = MainWindow()
    w.show()
    sys.exit(app.exec_())

The result.

Note: this work is tested with pyqt5, pyside2, pyside6 and should work in qt5 as well (in c++).

Answered By - Ted