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.