[Qt-interest] changing the way semected items of a QTableView do appear

[TP]

Hello,

The default appearance of selected items in a QTableView is a white color 
for the foreground (text), and dark blue for the background.
My goal is to change it:
* no color at all for the background (not white, because I want to continue 
seeing the pattern Qt::DiagCrossPattern with which I have filled some items 
in my table).
* making a box appear around selected items (a dotted box), to indicate that 
the items are selected.

It seems it is impossible to do with a custom delegate, because there is no 
"SelectionRole", or "isSelected" method for a QModelIndex.
And a style sheet is not suited either: if I set the following StyleSheet:

QTableView {
selection-background-color: rgba(255, 255, 255, 0%);
}

, I obtain the result that the selected items are completely white (text and 
background), and the patterns filled by my delegate disappear.

It seems to me there are other solutions:
* derive a QStyle?
* derive QTableView and its paintEvent? I am not familiar to this low-level 
approach.

What solution is the better?  What is its level of difficulty?

Thanks,

Julien
-- 
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9&1+,\'Z4(55l4('])"

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