def METHOD_NAME(self, content):
    r"""Add double rows of content to the toolbar.
    Parameters
    ----------
    content : list
        A list of content widgets.
    """
    self._items += content
    for i, c in enumerate(content):
        if not i % 2:
            if i > 0:
                self.addWidget(w)
            if self.orientation() == QtCore.Qt.Horizontal:
                l = QtWidgets.QVBoxLayout()
                l.setContentsMargins(6, 6, 6, 6)
            else:
                l = QtWidgets.QHBoxLayout()
                l.setContentsMargins(6, 6, 6, 6)
            l.setSpacing(12)
            w = QtWidgets.QWidget()
            w.setLayout(l)
        l.addWidget(c)
    if not i % 2:
        l.addStretch()
    self.addWidget(w)