resize by clicking the column edges

Nevez

hello, there is a tableview as in the picture. I want to adjust the width of the column by clicking and dragging the edges of the column on this view. (not by clicking on the header).

How can I do that ? any idea ?
Thanks.

Christian Ehrlicher

@Nevez said in resize by clicking the column edges:

How can I do that ? any idea ?

Since it's not supported out-of the box you have to derive from QTableView and implement it by yourself.

Nevez

I understood. So which functions should I focus on exactly?
can you explain a little bit

JonB

@Nevez
It seems to me that if you won't use the existing header-only drag-resize facility of QHeaderView you are going to have to do the whole thing yourself. You will need to:

Recognize a mouse-down anywhere over the QTableView (or its viewPort()).
Look at its horizontal position to determine whether it is "close enough" to an existing column divider to count as having moused-down on a column "edge". This is complex, allowing for viewport, "visual indexes", whether the table view has been scrolled horizontally, etc.
Do some kind of "drag" operation, showing a divider line.
Figure out the final, new width you want to adjust the column to.

You could take a a look e.g. https://codebrowser.dev/qt5/qtbase/src/widgets/itemviews/qheaderview.cpp.html to see the kind of work it does. The code at void QHeaderView::mousePressEvent(QMouseEvent *e) shows how that starts a mouse-down operation, it includes

int handle = d->sectionHandleAt(pos);
...
} else if (sectionResizeMode(handle) == Interactive) {

which is the resize-columns case.

Seems like an enormous amount of work, with all it has to deal with! I certainly would not want to do so :)

Maybe you could do something like recognise when your mouse down is over a column divider and then somehow forward it to the QHeaderView at the corresponding horizontal place, so that you then get it to handle the drag-resize for you, but that may be messy/not easy.

Nevez

Thanks for your comment. I guess I'll have to give up on this method.