PyQt QWebkitWidgets not displaying web page when called from command line or object constructor

Question

from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtWebKit import *
from PyQt5.QtWebKitWidgets import *
from PyQt5.QtWidgets import QApplication, QWidget, QMainWindow
import sys
import os

class Navigation(QWidget):
    def __init__(self):
        super().__init__()
        self.web = QWebView()
        self.web.settings().setAttribute(QWebSettings.
             JavascriptEnabled,True)
        #self.web.settings().setAttribute(QWebSettings.
        #    JavascriptCanOpenWindows, True)
        self.web.settings().setAttribute(QWebSettings.
            JSAC, True)

        #self.web.settings().setAttribute(QWebSettings.
        #DeveloperExtrasEnabled, True)
        filepath = os.path.join(
            os.path.dirname(__file__), 'MapSite.html')
        self.web.show()
        self.web.load(QUrl.fromLocalFile(filepath))

app = QApplication(sys.argv)
ex= Navigation()
app.exec_()

This PyQt program display a webpage only when run from IDLE for python3. When I run this program fom command line or make a Navigation class object by importing in other files, the webpage not displayed, just white screen

EDIT

pi@raspberrypi:~/RaspiCallSystem4 $ python3 navigation.py 
libEGL warning: DRI2: failed to authenticate
qt5ct: using qt5ct plugin
qt5ct: D-Bus system tray: no

when I execute from command line It give above output, web window starts but with white page only, running from IDLE executes smoothly

enter image description here

How do you execute the file in the command line? Is the cmd or terminal open in the path where the .py and .html file are located? — eyllanesc, Sep 10 '18 at 17:16
sorry I run on terminal using "python3 navigation.py" and yes terminal opened in that path — Ubaid ur Rehman Soomro, Sep 10 '18 at 17:23
In the RaspiCallSystem4 folder are the .py and the .html? On the other hand, have you been able to run QtWebKit on raspberry pi? that I know did not have support for it. — eyllanesc, Sep 10 '18 at 17:25
please show how you execute the command and all the messages that the console sends you, it is important to understand where the problem is — eyllanesc, Sep 10 '18 at 17:26
libEGL warning: DRI2: failed to authenticate qt5ct: using qt5ct plugin qt5ct: D-Bus system tray: no executing from command line give this output but web window still run with no white screen — Ubaid ur Rehman Soomro, Sep 10 '18 at 17:47
try changing `filepath` with fullpath. By other hand execute `print(filepath)` — eyllanesc, Sep 10 '18 at 17:48
yes, it's running on giving full path, but that's not friendly if path changed. So, whats the problem here @eyllanesc — Ubaid ur Rehman Soomro, Sep 10 '18 at 17:58

score 0 · Answer 1 · answered Sep 10 '18 at 18:09

As the following answer indicates in some cases the command os.path.dirname(__file__) can return an empty string, and that's the case of the terminal, so there are 2 possible solutions:

filepath = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'MapSite.html')

Or:

filepath = QDir.current().absoluteFilePath('MapSite.html')

PyQt QWebkitWidgets not displaying web page when called from command line or object constructor

1 Answers1