Flow layout manager positions children next to each other either horizontally or vertically. The manager sizes the children by using the preferred sizes of the children. IAlfLayoutPreferences::getPreferredSize() Flow layout manager takes system wide layout mirroring into consideration. In western locales the visuals are layed out from left to right whereas in arabic locale for instance the visuals are layed out from right to left. Mirroring is considered only when the flow is horizontal. The layout manager will always lay its children from top to bottom.