PyQt5 supports (native) file dialogs: open file, open files and save file. By calling the functions included in PyQt5 you get the default file dialog, you don't have to recreate these dialogs from scratch.

Importing QFileDialog is required.

Related course:
Practice Python with interactive exercises

File dialog example The methods used are QFileDialog.getOpenFileName(), QFileDialog.getOpenFileNames(), QFileDialog.getSaveFileName(). The method parameters let you specify the default directory, filetypes and the default filename.

The code below will show all file dialogs:

import sys
from PyQt5.QtWidgets import QApplication, QWidget, QInputDialog, QLineEdit, QFileDialog
from PyQt5.QtGui import QIcon
class App(QWidget):
def __init__(self):
        super().__init__()
        self.title = 'PyQt5 file dialogs - pythonspot.com'
        self.left = 10
        self.top = 10
        self.width = 640
        self.height = 480
        self.initUI()
    
    def initUI(self):
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)
        
        self.openFileNameDialog()
        self.openFileNamesDialog()
        self.saveFileDialog()
        
        self.show()
    
    def openFileNameDialog(self):
        options = QFileDialog.Options()
        options |= QFileDialog.DontUseNativeDialog
        fileName, _ = QFileDialog.getOpenFileName(self,"QFileDialog.getOpenFileName()", "","All Files (*);;Python Files (*.py)", options=options)
        if fileName:
            print(fileName)
    
    def openFileNamesDialog(self):
        options = QFileDialog.Options()
        options |= QFileDialog.DontUseNativeDialog
        files, _ = QFileDialog.getOpenFileNames(self,"QFileDialog.getOpenFileNames()", "","All Files (*);;Python Files (*.py)", options=options)
        if files:
            print(files)
    
    def saveFileDialog(self):
        options = QFileDialog.Options()
        options |= QFileDialog.DontUseNativeDialog
        fileName, _ = QFileDialog.getSaveFileName(self,"QFileDialog.getSaveFileName()","","All Files (*);;Text Files (*.txt)", options=options)
        if fileName:
            print(fileName)
if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    sys.exit(app.exec_())

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