Implement keyboard navigation for most widgets

[libs/gltk.git] / source / container.cpp

diff --git a/source/container.cpp b/source/container.cpp
index 068986b15aca7b329626974c6349941a8d68422f..b50bc29e2f9c120c5fee986fa319cafde6d8c459 100644 (file)
--- a/source/container.cpp
+++ b/source/container.cpp
@@ -302,6 +302,70 @@ void Container::focus_out()
        Widget::focus_out();
 }
 
+bool Container::navigate(Navigation nav)
+{
+       if(input_focus && input_focus->navigate(nav))
+               return true;
+
+       if(nav==NAV_UP || nav==NAV_DOWN || nav==NAV_LEFT || nav==NAV_RIGHT)
+       {
+               int x = geom.w/2;
+               int y = geom.h/2;
+               if(input_focus)
+               {
+                       const Geometry &fgeom = input_focus->get_geometry();
+                       x = fgeom.x+fgeom.w/2;
+                       y = fgeom.y+fgeom.h/2;
+               }
+               else if(nav==NAV_UP)
+                       y = 0;
+               else if(nav==NAV_DOWN)
+                       y = geom.h;
+               else if(nav==NAV_RIGHT)
+                       x = 0;
+               else if(nav==NAV_LEFT)
+                       x = geom.w;
+
+               Widget *sibling = 0;
+               int best_score = 0;
+               for(list<Child *>::const_iterator i=children.begin(); i!=children.end(); ++i)
+               {
+                       if((*i)->widget==input_focus || !(*i)->widget->is_focusable())
+                               continue;
+
+                       const Geometry &cgeom = (*i)->widget->get_geometry();
+                       int dx = cgeom.x+cgeom.w/2-x;
+                       int dy = cgeom.y+cgeom.h/2-y;
+
+                       int score = -1;
+                       if(nav==NAV_UP && dy>0)
+                               score = dy+abs(dx)*4;
+                       else if(nav==NAV_DOWN && dy<0)
+                               score = -dy+abs(dx)*4;
+                       else if(nav==NAV_RIGHT && dx>0)
+                               score = dx+abs(dy)*4;
+                       else if(nav==NAV_LEFT && dx<0)
+                               score = -dx+abs(dy)*4;
+
+                       if(score>0 && (!sibling || score<best_score))
+                       {
+                               sibling = (*i)->widget;
+                               best_score = score;
+                       }
+               }
+
+               if(sibling)
+               {
+                       set_input_focus(sibling);
+                       if(Container *container = dynamic_cast<Container *>(sibling))
+                               container->navigate(nav);
+                       return true;
+               }
+       }
+
+       return false;
+}
+
 void Container::on_reparent()
 {
        for(list<Child *>::iterator i=children.begin(); i!=children.end(); ++i)