Lv_label text with black background


Hi, @kisvegabor @embeddedt
I’m now current using LVGL 8.2 and would like to upgrade to LVGL 8.3
I’m using the same setting (code) to draw text, but now it somehow has black background (as figure below)
I’ve try setting bg_opa, but there is no any effect. (LV_COLOR_DEPTH 32)
Could anyone help?
I would be very grateful.

What LVGL version are you using?


What do you want to achieve?

draw lv_label text without black background. (transparent background)

What have you tried so far?

I’ve tried below style, but nothing help.
lv_obj_set_style_bg_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_color_filter_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_bg_img_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_bg_img_recolor_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_border_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_outline_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_shadow_opa(label, 0U, LV_PART_MAIN);
lv_obj_set_style_img_recolor_opa(label, 0U, LV_PART_MAIN);

Code to reproduce

Add a code snippet which can run in the simulator. It should contain only the relevant code that compiles without errors when separated from your main code base.

The code block(s) should be formatted like:

    lv_obj_t * label;
    lv_color_t label_color;
    label_color.full = Color;
    label = lv_label_create(...);
    lv_obj_add_style(label,&fontStyle_Big, LV_PART_MAIN);
    lv_obj_set_style_text_color(label,label_color, LV_PART_MAIN);
    //lv_obj_set_style_bg_opa(label, 0U, LV_PART_MAIN);

Screenshot and/or video

I wonder does anyone can help?
Or did anyone meet the situation before?

A few questions:

  • Are the colors correct? E.g. label_color is really red? And the blue border is really set to blue?
  • Is there any special things in the driver? E.g. transparent screen?

After I set driver with screen_transp =1U, background color disappears!
Many thanks for your clue.

@kisvegabor ,
sorry but I still want to know if it is necessary to enable screen_transp =1 with my case?
Since in previous version (before lvgl 8.2), I don’t need to enable this.

Please answer the questions in my previous comment so tat I can better understand your case.