equal
  deleted
  inserted
  replaced
  
    
    
|         |      1 LayoutManager | 
|         |      2   VerticalLayout | 
|         |      3   HorizontalLayout | 
|         |      4   TileLayout | 
|         |      5  | 
|         |      6  | 
|         |      7 events: | 
|         |      8  | 
|         |      9   draw() | 
|         |     10     - caller | 
|         |     11   on_draw() | 
|         |     12     - core handler, for overloading | 
|         |     13   connect('draw', my_draw) | 
|         |     14     - additional handler | 
|         |     15  | 
|         |     16  | 
|         |     17 Focus | 
|         |     18 ----- | 
|         |     19  | 
|         |     20  * only one node in hierarchy can have focus | 
|         |     21  * all parent containers have focus, so they can relay events to child | 
|         |     22  * top container has always focus | 
|         |     23  | 
|         |     24  * grab_focus() on any node will clean old focus and set focus to this child | 
|         |     25  * global shortcuts can be handled in keypress handler of top widget |