General and Desktop

@kapabahwuk There is Qt documentation for a reason...

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@Christian-Ehrlicher solved, ty

@sevi78 I found something interesting when I searched for qt game development. Qt Game Engine (QGE) It's a bit old but it might give you ideas even if it does not work for you. here's the link: Qt Game Engine You should also check out games that were made with Qt.

@Dan-Lyke a quick look at your code reminded me of another project where latency was crucial and I wrote a QIODevice subclass on top of PortAudio which might be better suited for your use case. On a side note, your custom mutex locker class is not necessary since there's QMutexLocker.

@Christian-Ehrlicher thank's very much ^^ It works fine now

@Christian-Ehrlicher as previously suggested I created my own topic here

@Chris-Kawa thank for ur explaination. after custom my delegate , i solved this problem.[image: pp3lToj.jpg] and when click double value item, should reimplement setEditorData function to specify the format,otherwise the double value will shrink too. below is my key code,hope it helps someone else. QWidget* XtrTaskViewDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const { return QStyledItemDelegate::createEditor(parent, option, index); } void XtrTaskViewDelegate::setEditorData(QWidget* editor, const QModelIndex& index) const { if (index.data().type() == QVariant::Double) { QDoubleSpinBox* doubleSpinBox = static_cast<QDoubleSpinBox*>(editor); doubleSpinBox->setDecimals(10); doubleSpinBox->setValue(index.data().toDouble()); } else { QStyledItemDelegate::setEditorData(editor, index); } }

@Sakhana99 It would then be good to list what platform(lin,win,mac) and what Qt version(Qt5.13,Qt6 etc) you are trying this on as things change in 7 years :)

I find QMLSCENE_DEVICE=softwarecontext in my OS，VideoOuput cannot use software to render. Qt Quick Software Adaptation

@ikuris said in QDataStream >> uin64_t: So this is the reason why it does compile on Windows Already explained: unsigned long long != unsigned long int

@Bonnie : Thanks for the recommendations I will go through the documentation and see if I am able to get the recording and playback to work

@ChrisW67 Thank you so much for fast response

@GSG As noted in the QLinkedList documentation: Note: This class is obsolete, please use std::list instead. So it is Qt team's suggestion to use std::list to replace it.

@masa4 said in QGraphicsView and some related problems: void MainWidget::DrawImage() { scene->clear(); if(!img.empty()){ img.convertTo(imgProcessed, -1, contrast, brightness); qimg = QImage(imgProcessed.data, imgProcessed.cols, imgProcessed.rows, imgProcessed.step, QImage::Format_Grayscale8); scaledQimg = qimg.scaled(ui->graphicsView->width() - 10, ui->graphicsView->height() - 10, Qt::KeepAspectRatio); if(isImageScaled) pixmap = QPixmap::fromImage(scaledQimg); else pixmap = QPixmap::fromImage(qimg); pix = scene->addPixmap(pixmap); ui->graphicsView->setScene(scene); } } There in the line where you call addPixmap. This create a new object every time. This answers question 1 For question 2, retry when you stopped adding all these objects. For question 3, do you mean you find complicated to manage two QImage objects ? Why are you creating two images and then selecting one of the two ? Move all the additional logic where it actually make sense then there's no need for multiple QImages. This will also avoid wasting CPU and RAM for nothing. For the bonus question, check the Gesture Overview in Qt's documentation

@sajis just as I wrote: go to Qt Creator's settings.

ok ! thanks SGaist.

@lukutis222 said in QCustomPlot rounded corners stylesheet without border-radius: From looking at the mainwindow.ui, I can see that the corners are rounded: However, when I build and run the application, corners are no longer rounded and the background color is not blue. This is what it looks like when the application is launched: Just because you've set a stylesheet to the widget in the place of QCustomPlot, it doesn't mean that the stylesheet is also applied to your plot. The same question was discussed in QCustomPlot forum here: https://www.qcustomplot.com/index.php/support/forum/1432 How come it shows up as rounded corners in mainwindow.ui Because QtDesigner is a "dumb" tool (not in terms of "bad", but it doesn't know about logic and the code you add later, when your widget is replaced with QCustomPlot) It's a WYSIWYG editor. When opening your mainWindow.ui in design mode, there is still just a plain QWidget, which is styled according to the stylesheet you've set. Something does not seem right, it feels like it is not applying the stylesheets properly. When rendering/painting the QCustomPlot, the stylesheet is probably ignored/not supported. For more information you should check the QCustomPlot documention and forum, since it's a third-party tool. https://www.qcustomplot.com/documentation/index.html Does it matter if this QCustomPlot widget is placed withing horizontal layout? Maybe that could be an issue? No, definitely not the issue.

@Yaldiz By default you only can set the line color and line width. https://doc.qt.io/qt-5/qml-qtlocation-mappolyline.html#details