The problem with your program is that you are attempting to create a new QApplication with every url you fetch. Instead, only one QApplication and one WebPage should be created. The WebPage can use its loadFinished signal to create an internal loop by fetching a new url after each one has been processed. Custom html … Read more
This is probably due to changes in the way exceptions are dealt with in PyQt-5.5. To quote from the PyQt5 Docs: In PyQt v5.5 an unhandled Python exception will result in a call to Qt’s qFatal() function. By default this will call abort() and the application will terminate. Note that an application installed exception hook … Read more
The problem is that the function that obtains the image is executed only once and not updating the label. The correct way is to place it inside a loop, but it will result in blocking the main window. This blocking of main window can be solved by using the QThread class and send through a … Read more
The QPushButton.clicked signal emits an argument that indicates the state of the button. When you connect to your lambda slot, the optional argument you assign idx to is being overwritten by the state of the button. Instead, make your connection as button.clicked.connect(lambda state, x=idx: self.button_pushed(x)) This way the button state is ignored and the correct … Read more
The answer to your question’s title is “yes”: I recommend never using from … import *, and I discussed the reasons in another very recent answer. Briefly, qualified names are good, barenames are very limited, so the “third option” is optimal (as you’ll be using qualified names, not barenames) among those you present. (Advantages of … Read more
This was discussed not too long ago in PyQt mailing list. Quoting Giovanni Bajo’s comments on the subject: It’s mostly the same. The main difference is that QThreads are better integrated with Qt (asynchrnous signals/slots, event loop, etc.). Also, you can’t use Qt from a Python thread (you can’t for instance post event to the … Read more
It shouldn’t matter whether the connection is made before or after moving the worker object to the other thread. To quote from the Qt docs: Qt::AutoConnection – If the signal is emitted from a different thread than the receiving object, the signal is queued, behaving as Qt::QueuedConnection. Otherwise, the slot is invoked directly, behaving as … Read more
The problem can be solved in 2 ways: Using lambda functions: In general: obj.signal.connect(lambda param1, param2, …, arg1=val1, arg2= value2, … : fun(param1, param2,… , arg1, arg2, ….)) def fun(param1, param2,… , arg1, arg2, ….): […] where: param1, param2, … : are the parameters sent by the signal arg1, arg2, …: are the extra parameters … Read more
I created a little example that shows 3 different and simple ways of dealing with threads. I hope it will help you find the right approach to your problem. import sys import time from PyQt5.QtCore import (QCoreApplication, QObject, QRunnable, QThread, QThreadPool, pyqtSignal) # Subclassing QThread # http://qt-project.org/doc/latest/qthread.html class AThread(QThread): def run(self): count = 0 while … Read more
Actually i was looking for time.sleep alternative to use in pyqt without using any thread concepts. And the solution i figured out is: from PyQt4 import QtTest QtTest.QTest.qWait(msecs) This works similar to time.sleep making GUI responsive. Thankyou for your answers.