LuatOS/demo/lvgl/win32/lvgl_demo_test/btnmatrix_demo.lua

local btnmatrix_demo = {}

local function event_handler(obj, event)
    if(event == lvgl.EVENT_VALUE_CHANGED) then
            local txt = lvgl.btnmatrix_get_active_btn_text(obj)
            print(string.format("%s was pressed\n", txt))
    end
end

function btnmatrix_demo.demo()
    local btnm_map = {"1", "2", "3", "4", "5", "\n",
                    "6", "7", "8", "9", "0", "\n",
                    "Action1", "Action2",""}

    local btnm1 = lvgl.btnmatrix_create(lvgl.scr_act(), nil)
    lvgl.btnmatrix_set_map(btnm1, btnm_map)
    lvgl.btnmatrix_set_btn_width(btnm1, 10, 2)        --Make "Action1" twice as wide as "Action2"
    lvgl.btnmatrix_set_btn_ctrl(btnm1, 10, lvgl.BTNMATRIX_CTRL_CHECKABLE)
    lvgl.btnmatrix_set_btn_ctrl(btnm1, 11, lvgl.BTNMATRIX_CTRL_CHECK_STATE)
    lvgl.obj_align(btnm1, nil, lvgl.ALIGN_CENTER, 0, 0)
    lvgl.obj_set_event_cb(btnm1, event_handler)
end

return btnmatrix_demo