QTreeView doesn't expand

[midnightdim]

I'd like to display the tree expanded in QTreeView, and I'm using expandAll(). For some reason it doesn't work.
Here's the full working example (PySide2 can be replaced with PySide6):

import PySide2
from PySide2 import QtWidgets
from PySide2.QtWidgets import QFileSystemModel, QMainWindow, QWidget, QTreeView, QVBoxLayout
from PySide2.QtCore import QDir, QSortFilterProxyModel, Qt
import sys

class View(QMainWindow):
    def __init__(self):
        super().__init__()

        self._w_main = QWidget()
        self.setCentralWidget(self._w_main)
        self.tree_view = QTreeView(self._w_main)

        self._layout = QVBoxLayout()
        self._layout.addWidget(self.tree_view)
        self._w_main.setLayout(self._layout)

app = QtWidgets.QApplication([])
view = View()
model = QFileSystemModel()
model.setRootPath('.')
model.setFilter(QDir.NoDot | QDir.AllEntries)
model.sort(0, Qt.SortOrder.AscendingOrder)
view.tree_view.setModel(model)
view.tree_view.setRootIndex(model.index('.'))
view.tree_view.header().setSortIndicator(0, Qt.AscendingOrder)
view.tree_view.setSortingEnabled(True)
view.showMaximized()
view.tree_view.expandAll()

sys.exit(app.exec_())

Am I missing something trivial? I also tried to expand() at some index, didn't work either.

[mrjj]

Hi
QFileSystemModel uses a thread to populate the model over time.
try to hook up to
https://doc.qt.io/qt-5/qfilesystemmodel.html#directoryLoaded
and expand there.

[midnightdim]

@mrjj Thanks a lot! This seems to work.