File Open Mechanism - file

Question

I'm trying to create an application. The application gives the user 2 combo boxes. Combo Box 1 gives the first part of the file name the user wants, and Combo Box 2 gives the second part of the file name. E.g. Combo box 1 option 1 is 1 and Combo Box 2 option 1 is A; the selected file is 1_A.txt.
I have a load button which is to use the file name , and open a file with that name. If no file exists, the application opens a dialog saying "No Such File Exists"
from PySide import QtGui, QtCore
from PySide.QtCore import*
from PySide.QtGui import*
class MainWindow(QtGui.QMainWindow):
def __init__(self,):
QtGui.QMainWindow.__init__(self)
QtGui.QApplication.setStyle('cleanlooks')
#PushButtons
load_button = QPushButton('Load',self)
load_button.move(310,280)
run_Button = QPushButton("Run", self)
run_Button.move(10,340)
stop_Button = QPushButton("Stop", self)
stop_Button.move(245,340)
#ComboBoxes
#Option1
o1 = QComboBox(self)
l1 = QLabel(self)
l1.setText('Option 1:')
l1.setFixedSize(170, 20)
l1.move(10,230)
o1.move(200, 220)
o1.setFixedSize(100, 40)
o1.insertItem(0,'')
o1.insertItem(1,'A')
o1.insertItem(2,'B')
o1.insertItem(3,'test')
#Option2
o2 = QComboBox(self)
l2 = QLabel(self)
l2.setText('Option 2:')
l2.setFixedSize(200, 20)
l2.move(10,290)
o2.move(200,280)
o2.setFixedSize(100, 40)
o2.insertItem(0,'')
o2.insertItem(1,'1')
o2.insertItem(2,'2')
o2.insertItem(3,'100')
self.fileName = QLabel(self)
self.fileName.setText("Select Options")
o1.activated.connect(lambda: self.fileName.setText(o1.currentText() + '_' + o2.currentText() + '.txt'))
o2.activated.connect(lambda: self.fileName.setText(o1.currentText() + '_' + o2.currentText() + '.txt'))
load_button.clicked.connect(self.fileHandle)
def fileHandle(self):
file = QFile(str(self.fileName.text()))
open(file, 'r')
if __name__ == '__main__':
import sys
app = QtGui.QApplication(sys.argv)
window = MainWindow()
window.setWindowTitle("Test11")
window.resize(480, 640)
window.show()
sys.exit(app.exec_())
The error I'm getting is TypeError: invalid file: <PySide.QtCore.QFile object at 0x031382B0> and I suspect this is because the string described in the file handle isn't being inserted in the QFile properly. Can someone please help

Answer 1

The Python open() function doesn't have any knowledge of objects of type QFile. I doubt you actually need to construct a QFile object though.
Instead, just open the file directly via open(self.fileName.text(), 'r'). Preferably, you would do:
with open(self.fileName.text(), 'r') as myfile:
# do stuff with the file
unless you need to keep the file open for a long period of time

Answer 2

I came up with a solution also.
def fileHandle(self):
string = str(self.filename.text())
file = QFile()
file.setFileName(string)
file.open(QIODevice.ReadOnly)
print(file.exists())
line = file.readLine()
print(line)
What this does is that it takes the string of the filename field. Creates the file object. Names the file object the string, and then opens the file. I have exists to check if the file is there, and after reading the test document i have, ti seemed to work as I wanted.
Thanks anyway #three_pineapples, but I'm going to use my solution :P