Using a QQuickPaintedItem for the rendering. The item gets the library
name from the model and loads the decoration with its own decoration
plugin. Thus each preview has its own plugin which eliminates the need to
constantly recreate the decoration as it is done with the preview.
Having a QQuickItem gives new possibilities. The item accepts hover
events and forwards them as enter and leave events to the widgets inside
the decoration. By that the mouse interaction of e.g. Oxygen is still
functional. If the decoration uses the new update approach the bridge is
forwarding the updates to the item and triggering a repaint so we even
have animations in the preview although the widget is never shown.
This introduces quite some changes. We cannot include a QQuickView
directly in the QWidget based UI as a replacement for the
QDeclarativeView used before.
Instead a QScrollArea is used as replacement for the view and a
QQuickView is embedded into a widget container in the scroll area's
view port. This allows us to keep the existing semantic of having a
native scroll bar synced with the list view. It might be an idea to
change this to QtQuickControls in future.
As the list view is now only inside the scroll area we do not need to
pass the slider width to the root context and can by that more easily
calculate the width of one decoration.
Model is extended to support QML based Aurorae themes as well
the preview is able to handle it. For this a new qml component
is added which loads the decoration preview.
Stop at bounds while flicking to have a list which behaves in a
natural way on the desktop and ensure that the scrollbar
handles cannot overshoot the list.
Thanks to Nuno for providing the QML based scrollbar. Obviously
this does not improve the consistency with other widget styles, so
a proper solution is still required.
BUG: 291612
