QML and Qt Quick

@timob256 I entered "Qt Quick draw line" in Google and got this: https://doc.qt.io/qt-5/qml-qtquick-pathline.html

@Praveen-Illa This was solved in another forum. Please refer to below link for the solution https://stackoverflow.com/questions/69814505/how-to-capture-hide-key-event-in-qt-virtualkeyboard

@DiegOne said in How to save files from and to usb ?: QFileDialog::getExistingDirectory the usb path is here /media/username/ There may be more to be done: progress bar(hard to impossible to do on linux if file size is too big) stop in the middle of copying QFile::copy(srcPath, dstPath) is not optimized remind the user: do not remove usb in the middle of copy since usb can be damaged. it is better to add a button to let users remove usb safely.

Are you sure it's emply and not just not displayed in qDebug? what about qDebug() << meta_property.read(obj).value<QList<QPointF>>();?

Ok I found it : [image: 9a97c36e-9a72-4f52-b810-3518ddbf585d.JPG] I call this function each time the QSliderRange change : void Controller::updateBackground(QQuickItem* item){ if(item){ if(QGraphicsScene *scene = item->findChild<QGraphicsScene *>()){ for(QGraphicsItem *it : scene->items()){ if(QtCharts::QChart *chart = dynamic_cast<QtCharts::QChart *>(it)){ // Customize plot area background QImage background(item->width(), item->height(), QImage::Format_ARGB32); if (background.isNull()) continue; background.fill(QColor(Qt::white)); QPainter painter(&background); int margin = (item->height()-chart->plotArea().height()) /2; int hRed = (10- _pData->threshHigh)/10 * chart->plotArea().height(); int hGreen = _pData->threshLow/10 * chart->plotArea().height(); int hYellow = chart->plotArea().height() - hRed - hGreen; // Red zone painter.fillRect(0, 0, item->width(), margin + hRed, QBrush(QColor(255,50,50,128))); // Yellow zone painter.fillRect(0,margin+hRed, item->width(), hYellow, QBrush(QColor(235,220,50,128))); // Green zone painter.fillRect(0,margin+hRed+hYellow, item->width(), margin+hGreen, QBrush(QColor(100,150,100,128))); chart->setPlotAreaBackgroundBrush(background); chart->setPlotAreaBackgroundVisible(true); } } } } } By passing the ChartView as parameter : sThresh.first.onValueChanged: controller.updateBackground(chart) sThresh.second.onValueChanged: controller.updateBackground(chart)

@Psyduck0205 I too facing similar issue. I need to access list of qvariant from squish? Can you help me ?

Hi, You can take a look at the fortune example for a way of generating random text.

ugh. I guess this feature has just been broken for over a year with misleading documentation. no big deal. thanks for your help everybody. https://bugreports.qt.io/browse/QTBUG-86132

Ok, I figured it out ! The shader does not change the Image, it just draws something else on the shader item's position. The solution was pretty darn simple: make the Image invisible and let the shadereffect item handle all the rendering part.

Yes QList<QObject*> is working. But why QList<SENSOR*> work on my Desktop and not work on raspberry???

@DiegOne hmm, still rather strange

@fcarney I removed the Component but the error is the same: QML PropertyAnimation: Cannot animate non-existent property "y" But now the Item should have the y property, right?

It would appear to be that there is an environment variable that will do this, not perfectly, but certainly vastly better than previously. Sadly, the very limited documentation on it implies it is only something for development purposes, presenting a clumsy way to look at your app using different DPI settings. The following, placed in main.cpp, worked. Yes, it could be set in the environment as well, having first tested it as a .profile entry. qputenv("QT_FONT_DPI", QByteArray("96")); 96 DPI is just a reference value on which Qt should be doing the appropriate scaling internally. It could be almost anything and still achieve the same results. Virtual pixels are obviously used for GUI components, why not consistently for the fonts. Though we are seeing what appears like a font substitution as well. Best guess is that Arial is being substituted for Liberation Sans, even though Liberation Sans is installed on all systems and is specifically loaded by the application. For example, the zero is much narrower on my system than on the target, as is the case of the zero in Arial as opposed to Liberation Sans.

This is really informative.