how to increase the visible size of QTreeView

[Qt Enthusiast]

I have a QtreeView , in which I have three columns , on action I set width of first column is

class myView :public QTreeView {

};

myView::action() {
setColumnWidth(0,COLUMN_SIZE)
}

how to increase the visible size of the whole treeview in action1 so that my first and second column are at least visible

[mrjj]

Hi
Please play around with
http://doc.qt.io/qt-5/qtreeview.html#resizeColumnToContents