How to remove the outline and masks in the demo widget?


Hi there,

I am new here, and trying to play with lvgl with Linux. But unfortunly, the screen seems have some problems, please check the screenshot attached. Why there is outline of each element?

Note: There is no LCD in my board, So I used a virtual frame buffer. And then dump the memory and convert it to a bmp.

What MCU/Processor/Board and compiler are you using?


What LVGL version are you using?


What do you want to achieve?

how to remove the outline and mask of each element?

Screenshot and/or video


Thanks very much!

Hi @hfli ,

It looks at first glance as if you may have enabled the refresh debugging…

Check your “lv_conf.h” file and make sure:

 #define LV_USE_REFR_DEBUG 0 

is defined and rebuild LVGL.

Hope that helps…

Kind Regards,


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Hi pete,

Thank you. Yeah, that is the point. After I revert the LV_USE_REFR_DEBUG value to 0, everything goes well. Thanks again!

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