"ValueError: 'PySide6.QtGui.QPainter.drawText' called with wrong argument values" even though the arguments seem right

Opara

MRE:

from PySide6 import QtWidgets as qtw
from PySide6 import QtGui as qtg
from PySide6 import QtCore as qtc


class Delegate(qtw.QAbstractItemDelegate):
    def paint(self, painter, option, index):
        text = index.model().data(
            index, qtc.Qt.ItemDataRole.DisplayRole
        )

        text_rect = qtc.QRect(
            option.rect.left(),
            option.rect.top(),
            option.rect.width(),
            200
        )

        painter.drawText(text_rect, 0, text, text_rect)

    def sizeHint(self, option, index):
        return qtc.QSize(200, 200)


class Model(qtc.QAbstractListModel):
    def __init__(self) -> None:
        super().__init__()
        self._texts = ["text" for _ in range(10)]

    def rowCount(self, _) -> int:
        return 10

    def data(self, index, role):
        if not index.isValid():
            return None

        if role == qtc.Qt.ItemDataRole.DisplayRole:
            return self._texts[index.row()]
        
        return None

class MainWindow(qtw.QMainWindow):
    def __init__(self):
        super().__init__()

        delegate = Delegate(self)
        self._model = Model()
        self._view = qtw.QListView(self)
        self._view.setModel(self._model)
        self._view.setItemDelegate(delegate)

        self.setCentralWidget(self._view)
        self.show()


app = qtw.QApplication()
mw = MainWindow()
app.exec()

Error:

ValueError: 'PySide6.QtGui.QPainter.drawText' called with wrong argument values:
  PySide6.QtGui.QPainter.drawText(PySide6.QtCore.QRect(230, 10, 0, 200), 0, '', PySide6.QtCore.QRect(230, 10, 0, 200))
Found signature:
  PySide6.QtGui.QPainter.drawText(PySide6.QtCore.QRect, int, str, PySide6.QtCore.QRect)

One of the signatures I get on VSCode for painter.drawText:

def drawText(r: PySide6.QtCore.QRect, flags: int, text: str, br: PySide6.QtCore.QRect) -> None

The provided signatures and the passed arguments match, don't they? Could this be a bug in PySide6?
The code causing the error is in the paint method in the Delegate class.

JonB

@Opara said in "ValueError: 'PySide6.QtGui.QPainter.drawText' called with wrong argument values" even though the arguments seem right:

PySide6.QtGui.QPainter.drawText(PySide6.QtCore.QRect, int, str, PySide6.QtCore.QRect)

I don't actually see this on page https://doc.qt.io/qtforpython/PySide6/QtGui/QPainter.html. [Actually I do find it, but it is mis-documented!] Does it make any difference if you remove the second QRect parameter?

Opara

@JonB

[Actually I do find it, but it is mis-documented!]

Now that you mention it, the documentation for that drawText function does mention a boundingRect parameter but the function definition doesn't have it. Looks like the documentation might have just been copied from https://doc.qt.io/qt-6/qpainter.html#drawText-3 without any changes made, apart from the code.

Does it make any difference if you remove the second QRect parameter?

It works as one would expect with the second QRect removed.

JonB

@Opara
Indeed, it looks like something strange might be going on for that overload. The C++ shows it as being optional. I do not know why your original Python code was rejected. You might want to report this as a bug.

CristianMaureira

You can remove the last argument, and the code will work, but as Jon was mentioning, better to open a bug report. Can you please submit an issue into https://bugreports.qt.io/projects/PYSIDE with the same code? I think the problem lies in the signature selection, because we do apply some magic on top to use drawText with that signature and the optional argument:

      <modify-function signature="drawText(QRect,int,QString,QRect*)">                                
         <modify-argument index="4">                                                                   
           <remove-argument/>                                                                          
           <remove-default-expression/>                                                                
         </modify-argument>                                                                            
         <modify-argument index="return">                                                              
           <replace-type modified-type="QRect"/>                                                       
         </modify-argument>                                                                            
         <inject-code class="target" position="beginning">                                             
           <insert-template name="fix_args,QRect*"/>                                                   
         </inject-code>                                                                                                                   
       </modify-function>