@Jkimmy Thank you for your help.

Ok. I've found the answer.

I subclass the QTreeView and override the void resizeEvent(QResizeEvent* e) as shown:

void MyTreeView::resizeEvent(QResizeEvent *e) { if(model() != Q_NULLPTR){ model()->layoutChanged(); } QTreeView::resizeEvent(e); }

And it did the trick.

Had help from the Voidrealms Facebook group.

Besides what @Rondog mentions, you could also read about layouts
http://doc.qt.io/qt-5.5/designer-layouts.html

If you assign a layout to the window, and put the tab in it, Qt can then
automatically adjust the size if user resize the window.
It takes a little bit to learn layouts but the reward is great.

@mrjj
Oh thank you very much. It's a good thing to learn!

@morte What do you mean by not draws ? See if you get updated height inside the Component.

Well I found a solution. I post here so maybe it helps somebody.

You need to declare a global property which stores the height. For example : reViewHeight

Put the ListView inside a transparent Rectangle: rcView, and put the rectangle inside the ScrollView

Add: Component.onCompleted: { reViewHeight = reViewHeight + height} in your delegate definition

In the ListView add: onCountChanged: { rcView.height = reViewHeight }

Done !