How to add an Item to the specific index in the layout - qt

Question

I am following this example to create a Flow layout:
http://doc.qt.io/qt-4.8/qt-layouts-flowlayout-example.html
This doesn't have addToIndex(int _index) function, so I would like to implement this. Since this layout uses QLayoutItems, I would like to create a function which can insert an Item after the specific index.
How can I get the index of an Item as integer and insert to the layout?
UPDATE:
flowlayout.cpp
FlowLayout *flowLayout = new FlowLayout;
void FlowLayout::insertItem(int index, QLayoutItem *item)
{
if(itemList.size() < index)
{
itemList.append(item);
}
else
{
itemList.insert(index,item);
QRect tmp = this->geometry();
}
update();
}
flowwindow.cpp
void FlowWindow::addLineBreak()
{
flowbreak = new FlowLayoutButton(NULL);
QLayoutItem *item = new QWidgetItem(flowbreak);
flowlayout->insertItem(index, item);
//flowlayout->addWidget(flowbreak);
}
flowlayoutbutton.cpp constructor
FlowLayoutButton::FlowLayoutButton(QWidget *_parent):QWidget(_parent)
{
QBoxLayout *layout = new QHBoxLayout;
flowbreak = new QPushButton(tr("-------Label-------"));
flowbreak->setGeometry(0, 0, 200,20);
layout->addWidget(flowBreak);
setLayout(layout);
}

Answer 1

add the following method:
flowlayout.h:
class FlowLayout : public QLayout
{
public:
void insertWidget(int index, QWidget *w);
// rest of the class from the example
};
flowlayout.cpp:
// new method
void FlowLayout::insertWidget(int index, QWidget *w) {
addWidget(w);
itemList.move(indexOf(w), index);
}
now you can use it by just calling (assuming you have a pointer to the layout named flowLayout):
flowLayout->insertWidget(2,new QPushButton("Button"));