使用 QFileSystemModel 時索引 PyQt5 組合框

Question

我需要從文件目錄列表中選擇出現在組合框中的默認文件。 使用普通的組合框，使用 .findText 很容易找到您想要的值的索引，但這似乎不適用於 QFileSystemModel 組合框，可能是由於選項列表在目錄列表可以之前不會填充的方式有資源。

這是我嘗試過的：

import sys
import collections
from PyQt5 import QtCore, QtWidgets
from PyQt5.QtWidgets import QMainWindow, QLabel, QGridLayout, QWidget, QComboBox
from PyQt5.QtCore import QSize, QRect    

class ComboWindow(QMainWindow):
    def __init__(self):
        QMainWindow.__init__(self)

        self.setMinimumSize(QSize(640, 140))    
        self.setWindowTitle("Combobox example") 

        centralWidget = QWidget(self)          
        self.setCentralWidget(centralWidget)   

        # Create combobox and add items.
        self.fsm = QtWidgets.QFileSystemModel()        
        self.fsm.setNameFilters(["*.txt"]) 
        self.configComboBox = QtWidgets.QComboBox(self)
        self.configComboBox.setGeometry(QRect(40, 40, 491, 31))
        self.configComboBox.setObjectName(("comboBox"))
        self.configComboBox.setModel(self.fsm)                
        self.fsm.setFilter(QtCore.QDir.NoDotAndDotDot | QtCore.QDir.Files)        
        # "text_files" is a subdir of current dir with files 
        # example1.txt, example2.txt, example3.txt
        self.configComboBox.setRootModelIndex(self.fsm.setRootPath("text_files")) 
        # V V This section does not work V V
        index = self.configComboBox.findText(MainConfig.settings["default_txt_file"])
        self.configComboBox.setCurrentIndex(index)

class MainConfig:
    settings = collections.OrderedDict()  

    @staticmethod
    def createDefaultConfig(name):
        MainConfig.settings["default_txt_file"] = "example3.txt"     

if __name__ == "__main__":
    app = QtWidgets.QApplication(sys.argv)
    mainWin = ComboWindow()
    mainWin.show()
    sys.exit( app.exec_() )

Answer 1

正如我在這個答案中指出的那樣，QFileSystemModel 在新線程中異步加載，因此您必須使用 directoryLoaded 信號來了解信息加載完成的時間：

import collections
import os
import sys

from PyQt5.QtWidgets import (
    QApplication,
    QComboBox,
    QFileSystemModel,
    QMainWindow,
    QWidget,
)
from PyQt5.QtCore import pyqtSlot, QDir, QRect, QSize


class ComboWindow(QMainWindow):
    def __init__(self, parent=None):
        super(ComboWindow, self).__init__(parent=None)

        self.setMinimumSize(QSize(640, 140))
        self.setWindowTitle("Combobox example")

        centralWidget = QWidget(self)
        self.setCentralWidget(centralWidget)

        # Create combobox and add items.
        self.fsm = QFileSystemModel()
        self.fsm.setNameFilters(["*.txt"])
        self.configComboBox = QComboBox(self)
        self.configComboBox.setGeometry(QRect(40, 40, 491, 31))
        self.configComboBox.setObjectName(("comboBox"))
        self.configComboBox.setModel(self.fsm)
        self.fsm.setFilter(QDir.NoDotAndDotDot | QDir.Files)
        self.fsm.directoryLoaded.connect(self.on_directoryLoaded)
        current_dir = os.path.dirname(os.path.realpath(__file__))
        dir_path = os.path.join(current_dir, "text_files")
        self.configComboBox.setRootModelIndex(self.fsm.setRootPath(dir_path))

    @pyqtSlot(str)
    def on_directoryLoaded(self, path):
        index = self.configComboBox.findText(MainConfig.settings["default_txt_file"])
        self.configComboBox.setCurrentIndex(index)


class MainConfig:
    settings = collections.OrderedDict()

    @staticmethod
    def createDefaultConfig(name):
        MainConfig.settings["default_txt_file"] = name


if __name__ == "__main__":
    MainConfig.createDefaultConfig("example3.txt")
    app = QApplication(sys.argv)
    mainWin = ComboWindow()
    mainWin.show()
    sys.exit(app.exec_())