Why the horizontal scroll bar does not show up in PYQT6 QtextEdit widget

In the example below I am using PyQt6 to create text with long lines that exceed the QtextEdit widget’s viewing size vertically and horizontally. The vertical scroll bar shows up however, the horizontal scroll bar does not show up. Any help with this issue is appreciated.

import sys
from PyQt6.QtWidgets import (QApplication, QMainWindow, QPushButton,
    QWidget, QHBoxLayout, QVBoxLayout, QTextEdit)
from PyQt6.QtCore import QSize

class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Example")
        self.setContentsMargins(20,20,20,20)
        self.setFixedSize(QSize(800, 600)) 
        self.setWindowTitle("Example")     
        layout1 = QHBoxLayout()
        layout2 = QVBoxLayout()
        self.output_text = QTextEdit()
        self.button_start = QPushButton("Start")
        self.button_start.clicked.connect(self.start)
        layout1.addLayout(layout2)
        layout2.addWidget(self.output_text)
        layout2.addWidget(self.button_start)        
        widget = QWidget()
        widget.setLayout(layout1)
        self.setCentralWidget(widget)

    def start(self):
        for i in range (1, 30):
            self.output_text.append("Line " + str(i) + ": This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. ")
        
app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec()

Answer

If you want a horizontal scrollbar, you will need to set the QTextEdit column width higher than the QTextEdit area. So let’s say for example 1000 will work for your code.

import sys
from PyQt6.QtWidgets import (QApplication, QMainWindow, QPushButton,
    QWidget, QHBoxLayout, QVBoxLayout, QTextEdit)
from PyQt6.QtCore import QSize, Qt

class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Example")
        self.setContentsMargins(20,20,20,20)
        self.setFixedSize(QSize(800, 600)) 
        self.setWindowTitle("Example")     
        layout1 = QHBoxLayout()
        layout2 = QVBoxLayout()
        self.output_text = QTextEdit()
        self.output_text.setLineWrapColumnOrWidth(1000) #Here you set the width you want
        self.output_text.setLineWrapMode(QTextEdit.LineWrapMode.FixedPixelWidth)
        self.button_start = QPushButton("Start")
        self.button_start.clicked.connect(self.start)
        layout1.addLayout(layout2)
        layout2.addWidget(self.output_text)
        layout2.addWidget(self.button_start)        
        widget = QWidget()
        widget.setLayout(layout1)
        self.setCentralWidget(widget)

    def start(self):
        for i in range (1, 30):
            self.output_text.append("Line " + str(i) + ": This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. This is a long line. ")
        
app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec()

And here is the result:

Tell me if this wasn’t what you were looking for or if it doesn’t work for you.