def layoutVertically(self, children, separation=0):
    top = self.top
    rows = self.rows
    for view in children:
        preferredRows = view.preferredSize(max(0, rows), self.cols)[0]
        view.reshape(top, self.left, max(0, min(rows, preferredRows)), self.cols)
        delta = (view.rows + separation)
        top += delta
        rows -= delta
def layoutVertically(self, children, separation=0):
    top = self.top
    rows = self.rows
    for view in children:
        preferredRows = view.preferredSize(max(0, rows), self.cols)[0]
        view.reshape(top, self.left, max(0, min(rows, preferredRows)), self.cols)
        delta = (view.rows + separation)
        top += delta
        rows -= delta