Challenges in migration of Qt 4.8.2 project into Qt 5.7 and above

[anda_skoa]

Grids and Ellipses are created as graphics item and in future vendor company will also create some items as graphics Item.

Should be trivial to create these as custom QDeclarativeItems

In Qt 4.8.2 we used QDeclalativeItem to create some objects in QML and added it to QGraphicsScene.

Ah, ok, very hacky.

If you use a QDeclarativeView instead then you can use the same approach when moving to a QQuickWidget.

We used QQuickWidget to access Item form QML file and added it to QGraphicsScene.

Well, that's not possible since Qt5 QQuickItems are not QGraphicsItems.
QtQuick is rendered with an OpenGL based scene graph.

As far as I understood your setup you have these options:

1) Remove the usage of QML

2) Keep using QGraphicsView and just use QQmlEngine with custom types to create QGraphicItem based objects in QML

3) Move the Qt4 version to use QDeclarativeView and custom QDeclarativeItem and then port that almost unchanged to QtQuickWidget and custom QQuickPaintedItems.

Cheers,
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