使用瑞萨单片机驱动3.5寸屏,屏上采用lvgl 8.3图形库进行绘制界面;
现在想画出lvgl的图表中绘制折线图,在使折线图下方区域显示颜色及渐变色;

网络上搜索的结果:
lv_obj_t * chart;
chart = lv_chart_create(lv_scr_act(), NULL);
lv_obj_set_size(chart, 200, 150);
lv_obj_align(chart, NULL, LV_ALIGN_CENTER, 0, 0);
lv_chart_set_type(chart, LV_CHART_TYPE_LINE); /*Show lines and points too*/
/*Add a faded are effect*/
lv_obj_set_style_local_bg_opa(chart, LV_CHART_PART_SERIES, LV_STATE_DEFAULT, LV_OPA_50); /*Max. opa.*/
lv_obj_set_style_local_bg_grad_dir(chart, LV_CHART_PART_SERIES, LV_STATE_DEFAULT, LV_GRAD_DIR_VER);
lv_obj_set_style_local_bg_main_stop(chart, LV_CHART_PART_SERIES, LV_STATE_DEFAULT, 255); /*Max opa on the top*/
lv_obj_set_style_local_bg_grad_stop(chart, LV_CHART_PART_SERIES, LV_STATE_DEFAULT, 0); /*Transparent on the bottom*/
。。。。。。
但执行时提示“lv_obj_set_style_local_bg_opa”编译错误提示找不到该函数,改为lv_obj_set_style_bg_opa就可以,但是也提示找不到LV_CHART_PART_SERIES,是否是因为lvgl的版本不对,导致以前的demo不能用了?
请问如何实现图表中的折线下面区域添加颜色或渐变色的效果?