I am a Beginner. I do not understand this error message. Who can explain it to me. :-)
Attempting to set QLayout "" on Window "", which already has a layout
from PyQt5.QtCore import Qt
from PyQt5.QtWidgets import (
QApplication, QWidget, QMainWindow,
QVBoxLayout, QHBoxLayout, QFormLayout, QGridLayout, QStackedLayout,
QPushButton, QComboBox, QLineEdit, QCheckBox, QRadioButton,
)
class Window(QWidget):
def __init__(self):
super().__init__()
layVer = QVBoxLayout()
self.comBox = QComboBox()
self.comBox.addItems(["One", "Two", "Three"])
self.comBox.activated.connect(lambda x: self.onComBox(x))
layVer.addWidget(self.comBox)
self.setLayout(layVer)
layHor = QHBoxLayout()
self.cheBox1 = QCheckBox("A")
layHor.addWidget(self.cheBox1)
self.setLayout(layHor)
layVer.addLayout(layHor)
def onCheBox(self, s):
print(s)
def onComBox(self, s):
print(s, self.comBox.currentText())
if __name__ == "__main__":
app = QApplication([])
win = Window()
win.show()
app.exec_()
PedanticHacker
Firstly, delete the line
self.setLayout(layVer)
then fix
self.setLayout(layHor)
layVer.addLayout(layHor)
to be
layVer.addLayout(layHor)
self.setLayout(layVer)
Martin Fitzpatrick
This error occurs because you're trying to set a layout on a QMainWindow. The
QMainWindow is a special widget which has a built-in layout, to handle things
link menus, toolbars and dock widgets.
For windows based on QMainWindow you can only set a central widget -- that is, the
widget that appears in the center of the window. But if you remember from the
PyQt5 layouts tutorial you can set a layout on an empty QWidget
and add anything you want to it that way.
So the trick is: for controlling the layout of a mainwindow we first create a QWidget to act
as a "container", use that widget as our central widget and apply the layout to it to add
other widgets.
_Ali Sanawi Garrousi__
Merci now it works!
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