Hello Eric,
Yes, I’ve just tested the code myself and it looks like the style is not being properly applied. I’ll provide a solution on Monday.
Thank you for your patience.
Regards,
Rui

Hello Rui
Thank you very much. 
just let us know when this is fixed so that we can test it again

Hello again!
I think during the code explanation, we might have removed the original styles from the code by mistake. Here’s the updated code:

• https://gist.githubusercontent.com/RuiSantosdotme/4da240faba824c4b8ac1e24078c93fea/raw/057c5b12930c59f88eb9e27655715bfc79b1b1df/2_4_Button.ino

Basically, we’ve added these lines to apply the border and shadow styles to the button pressed styled:

// Create a style for the button pressed state
// Use a color filter to simply modify all colors in this state and apply a dark effect
static lv_color_filter_dsc_t color_filter;
lv_color_filter_dsc_init(&color_filter, darken);
lv_style_init(&style_button_pressed);
lv_style_set_color_filter_dsc(&style_button_pressed, &color_filter);
lv_style_set_color_filter_opa(&style_button_pressed, LV_OPA_10);
lv_style_set_border_color(&style_button_pressed, lv_palette_main(LV_PALETTE_GREEN));
lv_style_set_border_opa(&style_button_pressed, LV_OPA_100);
lv_style_set_border_width(&style_button_pressed, 4);
lv_style_set_shadow_width(&style_button_pressed, 20);
lv_style_set_shadow_offset_y(&style_button_pressed, 5);
lv_style_set_shadow_opa(&style_button_pressed, LV_OPA_100);

Let me now if this new example works for you.
Regards,
Rui

It works now, thanks!

Ah ! I had the same issue, but thought it had to do with my specific CYD (E32R28T).
It works for me too now, which means that the link in the e-book is not updated yet…
Martin

Hi.
Yes, you’re right.
The link in the eBook will only be updated for version 1.6 of the eBook.
Regards,
Sara