pyqt QFileSystemModel rowCount

Question

我发现有关QFileSystemModel rowCount的帖子无法正常工作（ex1，ex2），但我似乎遗漏了一些东西。以下代码始终报告rowCount为1，即使列表显示更多...等待10秒后。我在这里缺少什么？

import os, sys
from PyQt5 import QtWidgets, QtCore


class TestWindow(QtWidgets.QMainWindow):
    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.model = QtWidgets.QFileSystemModel()
        self.model.setFilter(QtCore.QDir.AllEntries | QtCore.QDir.Hidden | QtCore.QDir.NoDot)
        self.path = os.path.expanduser('~')
        self.model.setRootPath(self.path)
        view = QtWidgets.QListView()
        view.setModel(self.model)
        view.setRootIndex(self.model.index(self.path))
        self.setCentralWidget(view)
        self.model.directoryLoaded.connect(self._loaded)
        QtCore.QTimer.singleShot(10000, self._really_loaded)

    def _loaded(self):
        print('_loaded', self.path, self.model.rowCount())  # Always returns 1 here? even though there are more rows displayed

    def _really_loaded(self):
        print('_really_loaded', self.path, self.model.rowCount())  # 10 seconds later...Always returns 1 here? even tho there are more rows displayed


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    test = TestWindow()
    test.show()
    sys.exit(app.exec_())

...为了理智......与pyqt4相同的代码具有相同的结果

import os, sys
from PyQt4 import QtGui, QtCore


class TestWindow(QtGui.QMainWindow):
    def __init__(self):
        QtGui.QMainWindow.__init__(self)
        self.model = QtGui.QFileSystemModel()
        self.model.setFilter(QtCore.QDir.AllEntries | QtCore.QDir.Hidden | QtCore.QDir.NoDot)
        self.path = os.path.expanduser('~')
        self.model.setRootPath(self.path)
        view = QtGui.QListView()
        view.setModel(self.model)
        view.setRootIndex(self.model.index(self.path))
        self.setCentralWidget(view)
        self.model.directoryLoaded.connect(self._loaded)
        QtCore.QTimer.singleShot(10000, self._really_loaded)

    def _loaded(self):
        print('_loaded', self.path, self.model.rowCount())  # Always returns 1 here? even though there are more rows displayed

    def _really_loaded(self):
        print('_really_loaded', self.path, self.model.rowCount())  # 10 seconds later...Always returns 1 here? even tho there are more rows displayed


if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    test = TestWindow()
    test.show()
    sys.exit(app.exec_())

Answer 1

您必须传递要分析的项目的索引，如果您想知道自己有多少项目，请使用返回setRootPath()的索引。

import os, sys
from PyQt5 import QtWidgets, QtCore


class TestWindow(QtWidgets.QMainWindow):
    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.model = QtWidgets.QFileSystemModel()
        self.model.setFilter(QtCore.QDir.AllEntries | QtCore.QDir.Hidden | QtCore.QDir.NoDot)
        self.path = os.path.expanduser('~')
        self.parentIndex  = self.model.setRootPath(self.path)
        view = QtWidgets.QListView()
        view.setModel(self.model)
        view.setRootIndex(self.model.index(self.path))
        self.setCentralWidget(view)
        self.model.directoryLoaded.connect(self._loaded)
        QtCore.QTimer.singleShot(10000, self._really_loaded)

    def _loaded(self, path):
        print('_loaded', self.path, self.model.rowCount(self.parentIndex))  # Always returns 1 here? even though there are more rows displayed

    def _really_loaded(self):
        print('_really_loaded', self.path, self.model.rowCount(self.parentIndex))  # 10 seconds later...Always returns 1 here? even tho there are more rows displayed


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    test = TestWindow()
    test.show()
    sys.exit(app.exec_())