Layout managers control the position, size, and arrangement of all the widgets inside the container. The qooxdoo framework provides different layout managers for different purposes, for example, to arrange widgets horizontally or vertically, to place the widgets in rows and columns such as in a grid, to place the widgets at the corners, to place the widgets at fixed points, and so on.
When a user resizes the web page, the qooxdoo layout engine prompts the layout manager to recalculate and reposition the widgets in the container.
The different criteria or properties involved in laying out the screen are discussed in the sections that follow.
Size hint is nothing but a map of boundaries, ...