<![CDATA[Dynamic qml object creation from c++ code]]>I want to strongly separate app logic on c++ and gui on qt quick. I have map (2d array) of cells with deferent properties, which will be modified during app lifecycle. Size of map also can vary. I have cell.qml that describes how cell should look like. But i don't understand how to dynamically create certain amout of cells in qml from cpp code. For example, at initialization, when i create c++ object i need corresponding qml object to be created as well.

]]>https://forum.qt.io/topic/95258/dynamic-qml-object-creation-from-c-codeRSS for NodeFri, 10 Apr 2026 07:05:34 GMTThu, 04 Oct 2018 11:09:17 GMT60<![CDATA[Reply to Dynamic qml object creation from c++ code on Tue, 09 Oct 2018 14:04:06 GMT]]>@GrecKo You're right! I am defenetly doing some kind of Game of Life)
I've managed to create a map, using GridView and QAbstractListModel like in this video.
I also understood how to pass values using model's roles. Now I'm trying to find out how to pass user defined classes through QVariant. I guess i also should register my 'Cell' class with qmlRegisterType<>

]]>https://forum.qt.io/post/485955https://forum.qt.io/post/485955Tue, 09 Oct 2018 14:04:06 GMT<![CDATA[Reply to Dynamic qml object creation from c++ code on Fri, 05 Oct 2018 15:14:49 GMT]]>@FedorKozlov There's no need for a DelegateModel in your case.

You can display table data with a TableView, but you can also display data in a table like fashion with a GridView or even a Repeater with the delegates positionning themselves.

If I guessed right you are trying to do some kind of Game of Life in Qt Quick.
The position of your cells is just data, you don't really need a table model.

]]>https://forum.qt.io/post/485428https://forum.qt.io/post/485428Fri, 05 Oct 2018 15:14:49 GMT<![CDATA[Reply to Dynamic qml object creation from c++ code on Fri, 05 Oct 2018 14:51:22 GMT]]>Thank you all for your answers!

I believe as @GrecKo said QAbstractItemModel is what i really need.
Though, as i found here http://doc.qt.io/qt-5/qtquick-modelviewsdata-cppmodels.html
QAbstractItemModel presents a hierarchy of tables, but the views currently provided by QML can only display list data. In order to display the child lists of a hierarchical model, use the DelegateModel QML type

]]>https://forum.qt.io/post/485422https://forum.qt.io/post/485422Fri, 05 Oct 2018 14:51:22 GMT<![CDATA[Reply to Dynamic qml object creation from c++ code on Thu, 04 Oct 2018 15:14:57 GMT]]>@FedorKozlov
It's much easier to do QML tasks in QML. Create a QML method to do it and call it from C++ with QMetaObject::invokeMethod().

]]>https://forum.qt.io/post/485244https://forum.qt.io/post/485244Thu, 04 Oct 2018 15:14:57 GMT<![CDATA[Reply to Dynamic qml object creation from c++ code on Thu, 04 Oct 2018 13:07:08 GMT]]>For your usecase you should expose a QAbstractItemModel to your QML layer.
Then in QML you would use a Repeater that will instantiate a Cell for each row of your model.

]]>https://forum.qt.io/post/485222https://forum.qt.io/post/485222Thu, 04 Oct 2018 13:07:08 GMT<![CDATA[Reply to Dynamic qml object creation from c++ code on Thu, 04 Oct 2018 11:32:18 GMT]]>Hello @FedorKozlov.

From my point of view, if you want to trigger an action from the c++ side to qml side, you must use the signal/slot mechanism. Otherwise, you should have the object of your c++ class in qml, and if the user triggers an event, you provide a method to respond that action if it is required backend activity.

If you provide some code it would nice, your explication it is kind of abstract.

]]>https://forum.qt.io/post/485173https://forum.qt.io/post/485173Thu, 04 Oct 2018 11:32:18 GMT