I want a translucent rectangle to be drawn on top of all chart elements
Overlay any drawings on the chart
I start drawing on chart on LV_EVENT_DRAW_PART_END event.
I set transparency draw_rect_dsc.bg_opa = LV_OPA_10; But the rectangle is not at the top level and is not transparent.
static void cb_Chart(lv_event_t *e)
lv_obj_t *obj = lv_event_get_target(e);
lv_obj_draw_part_dsc_t *dsc = lv_event_get_draw_part_dsc(e);
lv_draw_rect_dsc_t draw_rect_dsc; lv_draw_rect_dsc_init(&draw_rect_dsc); draw_rect_dsc.bg_opa = LV_OPA_10; draw_rect_dsc.bg_color = lv_color_hex(0xff0000); lv_area_t a; a.x1 = obj->coords.x1 + 20; a.y1 = obj->coords.y1 + 20; a.x2 = obj->coords.x1 + 40; a.y2 = obj->coords.y1 + 80; lv_draw_rect(dsc->draw_ctx, &draw_rect_dsc, &a);
in main code
lv_obj_add_event_cb(Chart, cb_Chart, LV_EVENT_DRAW_PART_END, NULL);