SSD1306 Monochrome possible theme issues

How-to
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1

Context

For A project I am using an ESP32 with an SSD1306 Monochrome 128x64 Display. As a good starting point I am using an example from ESP-IDF. This works fine and is already configured to work with the display. Added some physical button controls and added piezo feedback, but I encountered some issues.

The situation

Labels show up fine, but a button does not show up, when I add them with a label. I assume it has something to do with the styling. This also goes for other widgets that miss neccesary styling, like scrollbars, panels,

So what I tried was checking the documentation about styling. And tried out setting some text colors (white or black), border colors, etc. But I got nothing. Labels work fine though, but can’t seem to set a border color or anything either.

Other things I found

I also found a post about setting a monochrome theme, which I (think) did by adding #define LV_THEME_DEFAULT_INIT lv_theme_mono_init at the top of my code (since the example from espressif declares configurations in the sdkconfig file.).

Any Input would be appreciated.

2

Hello, I’m using LVGL 8.3 with a similar chip (SSD1683) and seem to have the same problem. I can display a label and bitmaps without any problems, but a button or other widgets are not displayed at all or are displayed incorrectly.

Have you found a solution to the problem? I would really appreciate some help on this topic.

Thank you and best regards
Niklas

3

I had the same problem when using lvgl 9.2.2, but it was fixed when I used lvgl 8.0, and the edges of the buttons were displayed normally. I wonder if the newer version of lvgl has problems with monochrome display.

4

I’ve faced similar problems with monochrome displays in LVGL. It’s usually about adjusting the theme or widget styles. Using an older version like 8.0 often fixes the issue with buttons and widgets not showing properly. Have you tried using a different version or tweaking the theme?