how to create folder view in pyqt inside main window

Question

I'm trying to implement a folder viewer to view the structure of a specific path. and this folder view should look like a the tree widget in PyQT , i know that the file dialog can help , but i need to have it inside my main window.
i tried to implement this using QTreeWidget and i used a recursed function to loop inside folders, but this is too slow. since it needs to recurse around huge number of folders. is this the right way to do it? or there is a ready qt solution for this problem.
Check the figure below.

Answer 1

for PyQt5 I did this function :

def load_project_structure(startpath, tree):
    """
    Load Project structure tree
    :param startpath: 
    :param tree: 
    :return: 
    """
    import os
    from PyQt5.QtWidgets import QTreeWidgetItem
    from PyQt5.QtGui import QIcon
    for element in os.listdir(startpath):
        path_info = startpath + "/" + element
        parent_itm = QTreeWidgetItem(tree, [os.path.basename(element)])
        if os.path.isdir(path_info):
            load_project_structure(path_info, parent_itm)
            parent_itm.setIcon(0, QIcon('assets/folder.ico'))
        else:
            parent_itm.setIcon(0, QIcon('assets/file.ico'))

then i call it like this :

 load_project_structure("/your/path/here",projectTreeWidget)

and i have this result :

Answer 2

Use models and views.

"""An example of how to use models and views in PyQt4.
Model/view documentation can be found at
http://doc.qt.nokia.com/latest/model-view-programming.html.
"""
import sys

from PyQt4.QtGui import (QApplication, QColumnView, QFileSystemModel,
                         QSplitter, QTreeView)
from PyQt4.QtCore import QDir, Qt

if __name__ == '__main__':
    app = QApplication(sys.argv)
    # Splitter to show 2 views in same widget easily.
    splitter = QSplitter()
    # The model.
    model = QFileSystemModel()
    # You can setRootPath to any path.
    model.setRootPath(QDir.rootPath())
    # List of views.
    views = []
    for ViewType in (QColumnView, QTreeView):
        # Create the view in the splitter.
        view = ViewType(splitter)
        # Set the model of the view.
        view.setModel(model)
        # Set the root index of the view as the user's home directory.
        view.setRootIndex(model.index(QDir.homePath()))
    # Show the splitter.
    splitter.show()
    # Maximize the splitter.
    splitter.setWindowState(Qt.WindowMaximized)
    # Start the main loop.
    sys.exit(app.exec_())