The interface for layout managers

Layout manager handles the layouting of child widgets in the container widget. It uses IAlfLayoutPreferences-interface (IAlfLayoutPreferences) of child widgets as a guide for laying out the widgets. The layoutmanager is set to the IAlfHostApi- interface (IAlfHostApi::setBaseLayout) createLayout-method should be the first call after creating the layoutmanager.Layout manager may also provide information about the layout preferences of its children. If this is supported the layout manager will combine the layout preferences of its children taking into consideration the technique used to lay out the children using the layout manager. This will provide information about the whole display area occupied by the layout manager. For instance vertical flow layout manager will provide preferred size area of its children by summing their heights and providing the maximum width among the children.

 // Create layout manager interface.
 IAlfLayoutManager* layoutManager = IAlfInterfaceBase::makeInterface<IAlfLayoutManager>(control);

 // See if layout preferences is supported in the given layout manager.
 IAlfLayoutPreferences* layoutPreferences = IAlfInterfaceBase::makeInterface<IAlfLayoutPreferences>(layoutManager);

 if(layoutPreferences != 0)
     {
     TAlfXYMetric preferredSize;
     // This will report the preferred size of the layout by combining together preferred sizes of its children.
     bool result = layoutPreferences->getPreferredSize(preferredSize);
     }