dynamically populate comboBox Qt

Question

I am trying to write a small app that compares xml. But right I am having a hard time doing the UI. I have a button that triggers a QFileDialog. I take the string input and populate a combobox. Unfortunately, the combobox stays empty. It seems to work when I hardcode it. But I am unable to get the app to do it dynamically. Is there something I am missing?

Here's the code:

import sys
from qtpy import QtCore, QtWidgets, uic
from qtpy.QtWidgets import QMainWindow, QApplication, QFileDialog
from qtpy.QtCore import QObject

class CompareSiteAndRepoWindow(QMainWindow):

    def __init__(self):
        super(CompareSiteAndRepoWindow,self).__init__()
        uic.loadUi('CompareSiteAndRepo.ui',self)
        self.BrowseLRPath.clicked.connect(self.browseFile)
        self.buttonBox.rejected.connect(self.reject)

        self.show()

    def reject(self):
        self.close()

    def browseFile(self):

        fileDiag = QFileDialog.getOpenFileName(self, 'Open file', 
   'c:\\',"xml/html (*.xml *.html)")

        if(not fileDiag[0]):
            print(fileDiag[0])
            self.LRPathComboBox.addItem(fileDiag[0],0)



if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = CompareSiteAndRepoWindow()

    sys.exit(app.exec())

the CompareSiteAndRepo.ui file

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>CompareLabToSiteDLG</class>
 <widget class="QMainWindow" name="CompareLabToSiteDLG">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>316</width>
    <height>262</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QGridLayout" name="gridLayout">
    <item row="0" column="0">
     <layout class="QVBoxLayout" name="verticalLayout">
      <item>
       <widget class="QLabel" name="LRLabel">
        <property name="text">
         <string>Load Report</string>
        </property>
       </widget>
      </item>
      <item>
       <widget class="QSplitter" name="splitter">
        <property name="orientation">
         <enum>Qt::Horizontal</enum>
        </property>
        <widget class="QComboBox" name="LRPathComboBox"/>
        <widget class="QPushButton" name="BrowseLRPath">
         <property name="text">
          <string>Browse</string>
         </property>
        </widget>
       </widget>
      </item>
      <item>
       <widget class="QLabel" name="LP2Label">
        <property name="text">
         <string>LaunchPadData repo layout</string>
        </property>
       </widget>
      </item>
      <item>
       <widget class="QSplitter" name="splitter_2">
        <property name="orientation">
         <enum>Qt::Horizontal</enum>
        </property>
        <widget class="QComboBox" name="LP2RepoPath"/>
        <widget class="QPushButton" name="BrowseLP2RepoPath">
         <property name="text">
          <string>Browse</string>
         </property>
        </widget>
       </widget>
      </item>
      <item>
       <widget class="QDialogButtonBox" name="buttonBox">
        <property name="standardButtons">
         <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
        </property>
       </widget>
      </item>
     </layout>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>316</width>
     <height>26</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

Answer 1

the problem is the statement if (not fileDiag[0]):, fileDialog[0] is a text that if we evaluate it as boolean will return True for any text except it is empty and if you deny it will be False if the text is not empty or True if it is, which is contrary to what you want:

 fileDiag[0]    not fileDiag[0]
+--------------+--------------+
 ""              True
 "some text"     False

One solution is to suppress the not:

if fileDiag[0]:
    [...]

But another solution is to compare if the text is not empty as I show below:

def browseFile(self):
    filename, _ = QFileDialog.getOpenFileName(self, 'Open file', 'c:\\',"xml/html (*.xml *.html)")
    if filename != "":
        self.LRPathComboBox.addItem(filename, 0)