Check box - rockcastle/lvgl GitHub Wiki

Overview

The Check Box objects are built from a Button background which contains an also Button bullet and a label to realize a classical check box. The text can be modified by the lv_cb_set_text(cb, "New text") function.

An action can assigned by lv_cb_set_action(cb, action).

You can manually check / un-check the Check box via lv_cb_set_checked(cb, state).

Style usage

The Check box styles can be modified with lv_cb_set_style(cb, LV_CB_STYLE_..., &style).

• LV_CB_STYLE_BG Background style. Uses all style.body properties. The label's style comes from style.text. Default: lv_style_transp
• LV_CB_STYLE_BOX_REL Style of the released box. Uses the style.body properties. Default: lv_style_btn_rel
• LV_CB_STYLE_BOX_PR Style of the pressed box. Uses the style.body properties. Default: lv_style_btn_pr
• LV_CB_STYLE_BOX_TGL_REL Style of the checked released box. Uses the style.body properties. Default: lv_style_btn_tgl_rel
• LV_CB_STYLE_BOX_TGL_PR Style of the checked released box. Uses the style.body properties. Default: lv_style_btn_tgl_pr

Example

static lv_res_t cb_release_action(lv_obj_t * cb)
{
    /*A check box is clicked*/
    printf("%s state: %d\n", lv_cb_get_text(cb), lv_cb_is_checked(cb));

    return LV_RES_OK;
}

.
.
.


/********************************************
 * Create a container for the check boxes
 ********************************************/

/*Create  border style*/
static lv_style_t style_border;
lv_style_copy(&style_border, &lv_style_pretty_color);
style_border.glass = 1;
style_border.body.empty = 1;

/*Create a container*/
lv_obj_t * cont;
cont = lv_cont_create(lv_scr_act(), NULL);
lv_cont_set_layout(cont, LV_LAYOUT_COL_L);      /*Arrange the children in a column*/
lv_cont_set_fit(cont, true, true);              /*Fit the size to the content*/
lv_obj_set_style(cont, &style_border);

/**************************
 * Create check boxes
 *************************/

/*Create check box*/
lv_obj_t * cb;
cb = lv_cb_create(cont, NULL);
lv_cb_set_text(cb, "Potato");
lv_cb_set_action(cb, cb_release_action);

/*Copy the previous check box*/
cb = lv_cb_create(cont, cb);
lv_cb_set_text(cb, "Onion");

/*Copy the previous check box*/
cb = lv_cb_create(cont, cb);
lv_cb_set_text(cb, "Carrot");

/*Copy the previous check box*/
cb = lv_cb_create(cont, cb);
lv_cb_set_text(cb, "Salad");

/*Align the container to the middle*/
lv_obj_align(cont, NULL, LV_ALIGN_CENTER, 0, 0);