QML and Qt Quick

Are you wanting the Rectangle to exist when not visible or the data? If its the latter then take a data driven approach rather than messing with Items. You can build a ListModel in QML with your data and access the data inside that. Then it is primed to be used with various views.

@ocgltd EVERY property you use in a statement must either be CONSTANT or have a NOTIFY signal. depending on which property gets changed, this notifier signal causes a reevaluation of the property binding.

The problem is caused because I'm using Qt Virtual Keyboard but I don't know how to avoid it.

Networking is such a broad concept that if you don't have a specific use case it's hard to give advices. The client code for a REST API can be very boring. see this code I made a long time ago to display the bike share network of my city as an example : https://github.com/oKcerG/MeetupSFPMMap/blob/master/main.qml the code to fetch the data is barely 10 lines (and simple ones). The model is handled via https://github.com/benlau/qsyncable , don't populate data manually in a for loop like done in the QML book. For more advance use case you would use QNetworkAccessManager in C++, potentially with OAuth and expose a nice API to QML. Or maybe you need to use a third party lib or implement a binary protocol with QTcpSocket. Or maybe something with zmq or protobuf ...

@ocgltd Colors is a singleton, so why don't you create a c++ instance/get a reference and call the default color change setter there. After that you load your main.qml. Order of execution is important here.

@kk2507 You should start here: https://doc.qt.io/qt-5/qtserialport-index.html There is also link to examples.

@kk2507 Your are mixing up several things: error unknown module: do you have installed QSerialPort? By the way how did you install Qt and which version are you using?(not Qt Creator which is only an IDE) If there is no serial port not available in "Tera Term", it is perhaps because your PC does not have any serial port available?

@NullByte : I don't have any example implementing thins. But, with little effort, you can generate a random number and set the currentIndex for every Tumbler component. But I'm not sure how you can increase the speed to have a movement effect when incrementing the currentIndex. he movement effect can also be done by quickly incrementing the currentIndex. import QtQuick import QtQuick.Window import QtQuick.Controls ApplicationWindow { property var numItens: 5 Rectangle { anchors.fill: parent Row { Tumbler { id: tumbler1 model: numItens wrap: true } Tumbler { id: tumbler2 model: numItens wrap: true } Tumbler { id: tumbler3 model: numItens wrap: true } } Timer { id: incTimer1 property var counter: 0 property var frequency: 2 interval: 1000 / frequency repeat: true running: counter != 0 onTriggered: { tumbler1.currentIndex = counter % numItens; counter = counter-1 console.debug(incTimer1.counter + " " + tumbler1.currentIndex) } } MouseArea { id: playArea anchors.fill: parent onPressed: { incTimer1.startIndex = incTimer1.counter incTimer1.counter = 5*incTimer1.frequency + Math.floor(Math.random() * numItens) // 5 seconds + X variable time console.debug(incTimer1.counter) } } } }

Or use StackView, push or replace pages onto it and pop them when needed.

I've only just started using QT6, for me, just adding the import statement was not enough in my case. I had to use the maintenance tool to add the compatibility module. Notably, there is also no shortcut in Start Menu for the maintenance tool, which can be found in the installation folder of Qt itself.

https://www.qt.io/blog/qt-extras-modules-in-qt-6