//.edc file
collections {
   group { name: "color_layout";
      parts {
		 part { 
            name: "rectangle";
            type: RECT;
            description{ 
               state: "default" 0.0;
               color: 100 200 100 255;
               rel1.relative: 0.4 0.45;
               rel2.relative: 0.6 0.55;
            }
         }
      }
   }
   group { name: "black_layout";
      parts {
		 part { 
            name: "rectangle";
            type: RECT;
            description{ 
               state: "default" 0.0;
               color: 0 0 0 255;
               rel1.relative: 0.4 0.45;
               rel2.relative: 0.6 0.55;
            }
         }
      }
   }
}


//C code
static void set_layout(char* layout, appdata_s* ad) {
	char edj_path[PATH_MAX] = { 0, };
	app_get_resource(EDJ_FILE, edj_path, (int)PATH_MAX);

	//layout name equals corresponding group name in .edc file
	elm_layout_file_set(ad->layout, edj_path, layout);
}