//create target object for hover
Evas_Object *rect = evas_object_rectangle_add(evas_object_evas_get(ad->win));
evas_object_color_set(rect, 200, 0, 0, 255);
evas_object_move(rect, 100, 100);
evas_object_resize(rect, 100, 100);
evas_object_show(rect);

//create hover object
Evas_Object *hover = elm_hover_add(ad->win);

//set parent and target for hover object
elm_hover_parent_set(hover, ad->win);
elm_hover_target_set(hover, rect);

//set hover style (other options are: popout, menu, hoversel_vertical)
elm_object_style_set(hover, "default");

evas_object_show(hover);