Removing weired object left and right white border lines


I’m pretty new in lvgl. So I created an object and then added a label to it. I set the object background to a non-white colour (black). When I add text to the label for the first time, every thing’s OK, but when I update the label text, those white lines added to the left and right side of the label. I tried to remove them by setting border style to 0 but no success.

	static lv_style_t style_heading;
	lv_style_set_text_color(&style_heading, lv_color_hex(0xffff00));

	lv_obj_set_style_bg_color(lv_scr_act(), lv_color_hex(0xff0000), LV_PART_MAIN);
	lv_obj_t * heading_obj = lv_obj_create(lv_scr_act());
	lv_obj_set_size(heading_obj, 150, 150);
	lv_obj_set_style_bg_color(heading_obj, lv_color_hex(0x000000), LV_PART_MAIN);

	lv_obj_t * heading_label = lv_label_create(heading_obj);
	lv_obj_add_style(heading_label, &style_heading, LV_PART_MAIN);

	lv_label_set_text(heading_label, "H:0.0");
	lv_obj_set_content_width(heading_label, 100);
	lv_obj_add_event_cb(heading_label, heading_update_cb, LV_EVENT_REFRESH, NULL);

change the border and outline opacity to zero for the main part. that should make them disappear.

also what is happening in the heading_update_cb callback function?

Thanks a lot for your reply. I set both the outline and the border opa for the main part to 0 but the result was the same but when I revert back from v8.3 to v8.2, the problem is gone. I’m not sure if this is a known bug.

static void heading_update_cb(lv_event_t * e)
	lv_event_code_t code = lv_event_get_code(e);
	lv_obj_t * label = lv_event_get_target(e);
	float * test_num = e->param;

	if(code == LV_EVENT_REFRESH)
		lv_label_set_text_fmt(label, "H:%.1f", *test_num);

I chased down the issue and realized that external SDRAM was not configured properly and it causes this strange behaviour. I have no idea why lvgl v8.2 could mitigate/hide this issue.