catch link clicks in QtWebView and open in default browser - qt

Question

I am opening a page in QtWebView (in PyQt if that matters) and I want to open all links in the system default browser. I.e. a click on a link should not change the site in the QtWebView but it should open it with the default browser. I want to make it impossible to the user to change the site in the QtWebView.
How can I do that?
Thanks,
Albert

Answer 1

That does it:
import sys, webbrowser
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyQt4.QtWebKit import *
app = QApplication(sys.argv)
web = QWebView()
web.load(QUrl("http://www.az2000.de/projects/javascript-project/"))
web.page().setLinkDelegationPolicy(QWebPage.DelegateAllLinks)
def linkClicked(url): webbrowser.open(str(url.toString()))
web.connect(web, SIGNAL("linkClicked (const QUrl&)"), linkClicked)
web.show()
sys.exit(app.exec_())

Answer 2

Updated example for PyQt5 (the magic is to re-implement the "acceptNavigationRequest" method):
from PyQt5 import QtWidgets, QtCore, QtGui, QtWebEngineWidgets
class RestrictedQWebEnginePage(QtWebEngineWidgets.QWebEnginePage):
""" Filters links so that users cannot just navigate to any page on the web,
but just to those pages, that are listed in allowed_pages.
This is achieved by re-implementing acceptNavigationRequest.
The latter could also be adapted to accept, e.g. URLs within a domain."""
def __init__(self, parent=None):
super().__init__(parent)
self.allowed_pages = []
def acceptNavigationRequest(self, qurl, navtype, mainframe):
# print("Navigation Request intercepted:", qurl)
if qurl in self.allowed_pages: # open in QWebEngineView
return True
else: # delegate link to default browser
QtGui.QDesktopServices.openUrl(qurl)
return False
class RestrictedWebViewWidget(QtWidgets.QWidget):
"""A QWebEngineView is required to display a QWebEnginePage."""
def __init__(self, parent=None, url=None, html_file=None):
super().__init__(parent)
self.view = QtWebEngineWidgets.QWebEngineView()
self.page = RestrictedQWebEnginePage()
if html_file:
print("Loading File:", html_file)
self.url = QtCore.QUrl.fromLocalFile(html_file)
self.page.allowed_pages.append(self.url)
self.page.load(self.url)
elif url:
print("Loading URL:", url)
self.url = QtCore.QUrl(url)
self.page.allowed_pages.append(self.url)
self.page.load(self.url)
# associate page with view
self.view.setPage(self.page)
# set layout
self.vl = QtWidgets.QVBoxLayout()
self.vl.addWidget(self.view)
self.setLayout(self.vl)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
web = RestrictedWebViewWidget(url="YOUR URL") # or YOUR local HTML file
web.show()
sys.exit(app.exec_())

Answer 3

When you click a link that has the target="_blank" attribute, QT calls the CreateWindow method in QWebEnginePage to create a new tab/new window.
The key is to re-implement this method to, instead of opening a new tab, open a new browser window.
class WebEnginePage(QtWebEngineWidgets.QWebEnginePage):
def createWindow(self, _type):
page = WebEnginePage(self)
page.urlChanged.connect(self.open_browser)
return page
def open_browser(self, url):
page = self.sender()
QDesktopServices.openUrl(url)
page.deleteLater()
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.url = QUrl("https://stackoverflow.com/")
self.webView = QWebEngineView()
self.page = WebEnginePage(self.webView)
self.webView.setPage(self.page)
self.webView.load(self.url)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
web = MainWindow()
web.show()
sys.exit(app.exec_())