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@bd9a A short google for "lambda capture member variables" gave the following result: https://stackoverflow.com/questions/7895879/using-member-variable-in-lambda-capture-list-inside-a-member-function In short, you need to capture [this]: QTimer::singleShot(5000, this, [this]() { Regards

Hi, Move all the classes that you want to be able to use in both your application and plugin in a shared library and link your plugins as well as your application against said library.

@sdf1444 Hi, print("Hello World! Im a laser") self.Button.setText("On")

@jonb said in qDebug output the message from point to QString::toLocal8Bit().data();: It is not the answer to what I am interested in, which is how the value at a given memory location gets changed between two consecutive statements which read it. My question is what changes it between these two lines (simply because I am interested). And that's what I liked to point out: we are talking about accessing invalid memory. You simply cannot do that.

@mrjj Thanks for your help. I followed your lead -- the qt examples were fine as were the qcustomplot examples. However, I finally traced the issue to the settings of the pixel buffer ratio. One line of code resolved all the problems ui->plot->setBufferDevicePixelRatio(1.0); It seems the default (2.0) causes drawing large graphs to go very very slowly. Geoffrey

Ok so I managed to import the html by modeling my code similar to the example with: QString code = QStringLiteral("qt.jQuery('#first_page').load('html/first_page.html');"); //you can even nest it with: QString code = QStringLiteral( "qt.jQuery('#first_page').load('html/first_page.html', ()=>{" "qt.jQuery('#border_content').load('html/border_content.html', ()=>{" //some other html "qt.jQuery('#last_page').load('html/last_page.html');" "});" "});" ); unfortunately I now cannot use the qwebchannel.js script anymore and my css gets screwed :( even loading it with: QFile script_file(":/qtwebchannel/qwebchannel.js"); if(!script_file.open(QIODevice::ReadOnly)) qDebug()<<"Couldn't load Qt's QWebChannel API!"; QString qt_script = QString::fromLatin1(script_file.readAll()); script_file.close(); view->page()->runJavaScript(qt_script); did not help. Since it is a small project and I am on a short deadline right now I will put everything in one html file and mark this question als solved.

git revert or git reset --hard. If you are not using a version control system - well you've just learned an important lesson why it's a good idea to use such a system ;-) You can try ctrl+z but I doubt it will work.

@j-hilk Thanks for the answer. Let's get it straight! It's main.cpp where all Qt Widget/Quick projects start from when we hit Run. #include <QApplication> #include "client.h" int main(int argc, char *argv[]) { QApplication app(argc, argv); QApplication::setApplicationDisplayName(Client::tr("Fortune Client")); Client client; client.show(); return app.exec(); } The first lines are creating a QApplication object with two arguments, then setting the window's display name. We then instantiate our class called Client. So these stages plus object's creation are carried out (as compile time stage supposedly) until control reaches show() - showing the project's UI -, and app.exec - starting executing the project (run-time stage). From this point, Qt event loop begins. Now what are the cycles of it? How is the event loop divided into a number of cycles?

@kent-dorfman I tried. The lambda is not executed.

@bartoszpaj said in BindValue() in QPSQL is not working?: driver()->hasFeature(QSqlDriver::NamedPlaceholders) returns false. Good catch. I think it's because support for PostgreSQL 10 was added in a later version. If the version is not known to the driver it will fall back to the oldest.

@ronaldviscarral Thank you very much it works now.

Ah ha! Solved. I was using the wrong version of qmake to build the project. All sorted now.

doubtful...the json is a document format. so, to be parsed correctly it needs to be cached somewhere. The readall() pulls the whole document into memory so that it can be parsed.

@sgaist that's right! Thank you! QLineEdit *myLineEdit = new QLineEdit(this); QAction *myAction = myLineEdit->addAction(QIcon("test.png"), QLineEdit::TrailingPosition); connect(myAction, &QAction::triggered, this, &MyClass::onActionTriggered);

If I'm looking at the doc, I see: Header: #include <QGraphicsSvgItem> qmake: QT += svg Have you add this to your pro file ?

@christian-ehrlicher That's what I feared . so , thanks, i will manage with this.

@sonichy said in How to recognize QNetWorkReply.Error() form QNetWorkManager.get() or QNetWorkManager.put(): QNetworkAccessManager manager; Just for clarify, is your instance of QNetworkAccessManager still alive at the time your slots are called ? Because as you are declaring it on the stack, it may be already destroyed and I presume it will also destroy internal QNetworkReply objects.

Where did you open that thread ?

@iammhz said in Threads in PyQt and opencv: when i click other buttons , they can't access the Webcam What if you just have only one method/thread to access the webcam, independent on which button is actually pressed, and when the image is captured then pass that image to the specific processing method/thread depending on the button/effect pressed. This way you'll avoid the bottleneck of "sharing" the webcam among threads