lvgl/src/lv_widgets/lv_checkbox.c

/**
 * @file lv_cb.c
 *
 */

/*********************
 *      INCLUDES
 *********************/
#include "lv_checkbox.h"
#if LV_USE_CHECKBOX != 0

#include "../lv_misc/lv_debug.h"
#include "../lv_core/lv_group.h"
#include "../lv_themes/lv_theme.h"

/*********************
 *      DEFINES
 *********************/
#define LV_OBJX_NAME "lv_checkbox"

/**********************
 *      TYPEDEFS
 **********************/

/**********************
 *  STATIC PROTOTYPES
 **********************/
static lv_res_t lv_checkbox_signal(lv_obj_t * cb, lv_signal_t sign, void * param);
static lv_style_list_t * lv_checkbox_get_style(lv_obj_t * cb, uint8_t type);

/**********************
 *  STATIC VARIABLES
 **********************/
static lv_signal_cb_t ancestor_signal;

/**********************
 *      MACROS
 **********************/

/**********************
 *   GLOBAL FUNCTIONS
 **********************/

/**
 * Create a check box objects
 * @param par pointer to an object, it will be the parent of the new check box
 * @param copy pointer to a check box object, if not NULL then the new object will be copied from it
 * @return pointer to the created check box
 */
lv_obj_t * lv_checkbox_create(lv_obj_t * par, const lv_obj_t * copy)
{
    LV_LOG_TRACE("check box create started");

    /*Create the ancestor basic object*/
    lv_obj_t * cb = lv_btn_create(par, copy);
    LV_ASSERT_MEM(cb);
    if(cb == NULL) return NULL;

    if(ancestor_signal == NULL) ancestor_signal = lv_obj_get_signal_cb(cb);

    lv_checkbox_ext_t * ext = lv_obj_allocate_ext_attr(cb, sizeof(lv_checkbox_ext_t));
    LV_ASSERT_MEM(ext);
    if(ext == NULL) {
        lv_obj_del(cb);
        return NULL;
    }

    ext->bullet = NULL;
    ext->label  = NULL;

    lv_obj_set_signal_cb(cb, lv_checkbox_signal);

    /*Init the new checkbox object*/
    if(copy == NULL) {
        ext->bullet = lv_obj_create(cb, NULL);
        lv_obj_set_click(ext->bullet, false);

        ext->label = lv_label_create(cb, NULL);

        lv_checkbox_set_text(cb, "Check box");
        lv_btn_set_layout(cb, LV_LAYOUT_ROW_MID);
        lv_btn_set_fit(cb, LV_FIT_TIGHT);
        lv_btn_set_checkable(cb, true);
        lv_obj_add_protect(cb, LV_PROTECT_PRESS_LOST);

        lv_theme_apply(cb, LV_THEME_CHECKBOX);

    }
    else {
        lv_checkbox_ext_t * copy_ext = lv_obj_get_ext_attr(copy);
        ext->bullet            = lv_obj_create(cb, copy_ext->bullet);
        ext->label             = lv_label_create(cb, copy_ext->label);

        /*Refresh the style with new signal function*/
        //        lv_obj_refresh_style(cb);
    }

    LV_LOG_INFO("check box created");

    return cb;
}

/*=====================
 * Setter functions
 *====================*/

/**
 * Set the text of a check box. `txt` will be copied and may be deallocated
 * after this function returns.
 * @param cb pointer to a check box
 * @param txt the text of the check box. NULL to refresh with the current text.
 */
void lv_checkbox_set_text(lv_obj_t * cb, const char * txt)
{
    LV_ASSERT_OBJ(cb, LV_OBJX_NAME);

    lv_checkbox_ext_t * ext = lv_obj_get_ext_attr(cb);
    lv_label_set_text(ext->label, txt);
}

/**
 * Set the text of a check box. `txt` must not be deallocated during the life
 * of this checkbox.
 * @param cb pointer to a check box
 * @param txt the text of the check box. NULL to refresh with the current text.
 */
void lv_checkbox_set_text_static(lv_obj_t * cb, const char * txt)
{
    LV_ASSERT_OBJ(cb, LV_OBJX_NAME);

    lv_checkbox_ext_t * ext = lv_obj_get_ext_attr(cb);
    lv_label_set_text_static(ext->label, txt);
}

/*=====================
 * Getter functions
 *====================*/

/**
 * Get the text of a check box
 * @param cb pointer to check box object
 * @return pointer to the text of the check box
 */
const char * lv_checkbox_get_text(const lv_obj_t * cb)
{
    LV_ASSERT_OBJ(cb, LV_OBJX_NAME);

    lv_checkbox_ext_t * ext = lv_obj_get_ext_attr(cb);
    return lv_label_get_text(ext->label);
}

/**********************
 *   STATIC FUNCTIONS
 **********************/

/**
 * Signal function of the check box
 * @param cb pointer to a check box object
 * @param sign a signal type from lv_signal_t enum
 * @param param pointer to a signal specific variable
 * @return LV_RES_OK: the object is not deleted in the function; LV_RES_INV: the object is deleted
 */
static lv_res_t lv_checkbox_signal(lv_obj_t * cb, lv_signal_t sign, void * param)
{
    lv_res_t res;
    if(sign == LV_SIGNAL_GET_STYLE) {
        lv_get_style_info_t * info = param;
        info->result = lv_checkbox_get_style(cb, info->part);
        if(info->result != NULL) return LV_RES_OK;
        else return ancestor_signal(cb, sign, param);
    }

    /* Include the ancient signal function */
    res = ancestor_signal(cb, sign, param);
    if(res != LV_RES_OK) return res;
    if(sign == LV_SIGNAL_GET_TYPE) return lv_obj_handle_get_type_signal(param, LV_OBJX_NAME);

    lv_checkbox_ext_t * ext = lv_obj_get_ext_attr(cb);

    if(sign == LV_SIGNAL_STYLE_CHG) {
        const lv_font_t * font = lv_obj_get_style_text_font(ext->label, LV_LABEL_PART_MAIN);
        lv_coord_t line_height = lv_font_get_line_height(font);
        lv_coord_t leftp = lv_obj_get_style_pad_left(cb, LV_CHECKBOX_PART_BULLET);
        lv_coord_t rightp = lv_obj_get_style_pad_right(cb, LV_CHECKBOX_PART_BULLET);
        lv_coord_t topp = lv_obj_get_style_pad_top(cb, LV_CHECKBOX_PART_BULLET);
        lv_coord_t bottomp = lv_obj_get_style_pad_bottom(cb, LV_CHECKBOX_PART_BULLET);

        lv_obj_set_size(ext->bullet, line_height + leftp + rightp, line_height + topp + bottomp);
        lv_obj_set_state(ext->bullet, lv_obj_get_state(cb, LV_CHECKBOX_PART_BG));
    }
    else if(sign == LV_SIGNAL_PRESSED || sign == LV_SIGNAL_RELEASED || sign == LV_SIGNAL_PRESS_LOST ||
            sign == LV_SIGNAL_FOCUS || sign == LV_SIGNAL_DEFOCUS) {
        lv_obj_set_state(ext->bullet, lv_obj_get_state(cb, LV_CHECKBOX_PART_BG));
    }
    else if(sign == LV_SIGNAL_CONTROL) {
#if LV_USE_GROUP
        char c = *((char *)param);
        if(c == LV_KEY_RIGHT || c == LV_KEY_DOWN || c == LV_KEY_LEFT || c == LV_KEY_UP) {
            /*Follow the backgrounds state with the bullet*/
            lv_obj_set_state(ext->bullet, lv_obj_get_state(cb, LV_CHECKBOX_PART_BG));
        }
#endif
    }

    return res;
}


static lv_style_list_t * lv_checkbox_get_style(lv_obj_t * cb, uint8_t type)
{
    lv_style_list_t * style_dsc_p;

    lv_checkbox_ext_t * ext = lv_obj_get_ext_attr(cb);
    switch(type) {
        case LV_CHECKBOX_PART_BG:
            style_dsc_p = &cb->style_list;
            break;
        case LV_CHECKBOX_PART_BULLET:
            style_dsc_p = lv_obj_get_style_list(ext->bullet, LV_BTN_PART_MAIN);
            break;
        default:
            style_dsc_p = NULL;
    }

    return style_dsc_p;
}

#endif