lvgl/lv_objx/lv_ddlist.c

/**
 * @file lv_ddlist.c
 * 
 */


/*********************
 *      INCLUDES
 *********************/
#include "lv_conf.h"
#if USE_LV_DDLIST != 0

#include "lv_ddlist.h"
#include "../lv_draw/lv_draw.h"
#include "../lv_misc/anim.h"

/*********************
 *      DEFINES
 *********************/

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

/**********************
 *  STATIC PROTOTYPES
 **********************/
static bool lv_ddlist_design(lv_obj_t * ddlist, const area_t * mask, lv_design_mode_t mode);
static lv_action_res_t lv_ddlist_rel_action(lv_obj_t * ddlist, lv_dispi_t * dispi);
static void lv_ddlist_refr_size(lv_obj_t * ddlist, bool anim_en);
static void lv_ddlist_pos_act_option(lv_obj_t * ddlist);
static void lv_ddlists_init(void);

/**********************
 *  STATIC VARIABLES
 **********************/
static lv_ddlists_t lv_ddlists_def;	/*Default drop down list style*/
static lv_design_f_t  ancestor_design_f;
static const char * def_options[] = {"Option 1", "Option 2", "Option 3", ""};
/**********************
 *      MACROS
 **********************/

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

/*----------------- 
 * Create function
 *-----------------*/

/**
 * Create a drop down list objects
 * @param par pointer to an object, it will be the parent of the new drop down list
 * @param copy pointer to a drop down list object, if not NULL then the new object will be copied from it
 * @return pointer to the created drop down list
 */
lv_obj_t * lv_ddlist_create(lv_obj_t * par, lv_obj_t * copy)
{
    /*Create the ancestor drop down list*/
    lv_obj_t * new_ddlist = lv_page_create(par, copy);
    dm_assert(new_ddlist);
    
    /*Allocate the drop down list type specific extended data*/
    lv_ddlist_ext_t * ext = lv_obj_alloc_ext(new_ddlist, sizeof(lv_ddlist_ext_t));
    dm_assert(ext);

    /*Initialize the allocated 'ext' */
    ext->opt_label = NULL;
    ext->cb = NULL;
    ext->opened = 0;
    ext->act_opt = 0;

    /*The signal and design functions are not copied so set them here*/
    if(ancestor_design_f == NULL) ancestor_design_f = lv_obj_get_design_f(new_ddlist);

    lv_obj_set_signal_f(new_ddlist, lv_ddlist_signal);
    lv_obj_set_design_f(new_ddlist, lv_ddlist_design);

    /*Init the new drop down list drop down list*/
    if(copy == NULL) {
        ext->opt_label = lv_label_create(new_ddlist, NULL);
        lv_rect_set_fit(new_ddlist, true, false);
        lv_page_set_rel_action(new_ddlist, lv_ddlist_rel_action);
        lv_obj_set_style(new_ddlist, lv_ddlists_get(LV_DDLISTS_DEF, NULL));
        lv_ddlist_set_options(new_ddlist, def_options);
    }
    /*Copy an existing drop down list*/
    else {
    	lv_ddlist_ext_t * copy_ext = lv_obj_get_ext(copy);
        ext->opt_label = lv_label_create(new_ddlist, copy_ext->opt_label);
        lv_label_set_text(ext->opt_label, lv_label_get_text(copy_ext->opt_label));
        /*Refresh the style with new signal function*/
        lv_obj_refr_style(new_ddlist);
    }
    
    return new_ddlist;
}

/**
 * Signal function of the drop down list
 * @param ddlist pointer to a drop down list object
 * @param sign a signal type from lv_signal_t enum
 * @param param pointer to a signal specific variable
 * @return true: the object is still valid (not deleted), false: the object become invalid
 */
bool lv_ddlist_signal(lv_obj_t * ddlist, lv_signal_t sign, void * param)
{
    bool valid;

    /* Include the ancient signal function */
    valid = lv_page_signal(ddlist, sign, param);

    /* The object can be deleted so check its validity and then
     * make the object specific signal handling */
    if(valid != false) {
        lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);
        lv_ddlists_t * style = lv_obj_get_style(ddlist);

    	switch(sign) {
    		case LV_SIGNAL_CLEANUP:
    			/*Nothing to cleanup. (No dynamically allocated memory in 'ext')*/
    			break;
    		case LV_SIGNAL_STYLE_CHG:
    		    lv_obj_set_style(ext->opt_label, &style->list_labels);
    		    lv_ddlist_refr_size(ddlist, false);
    		    break;
    		default:
    			break;
    	}
    }
    
    return valid;
}

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

/**
 * Set the options in a drop down list
 * @param ddlist pointer to drop down list object
 * @param options an array of strings wit the text of the options.
 *                The lest element has to be "" (empty string)
 *                E.g. const char * opts[] = {"apple", "banana", "orange", ""};
 */
void lv_ddlist_set_options(lv_obj_t * ddlist, const char ** options)
{
    lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);

    lv_label_set_text(ext->opt_label, "");
    uint16_t i = 0;
    while(options[i][0] != '\0') {
        lv_label_append_text(ext->opt_label, options[i]);
        if(options[i + 1][0] != '\0') lv_label_append_text(ext->opt_label, "\n");
        i++;
    }

    lv_ddlist_refr_size(ddlist, false);
}

/**
 * Set a function to call when a new option is chosen
 * @param ddlist pointer to drop down list
 * @param cb pointer to a call back function. Its prototype is:
 *           parameter 1: pointer to the drop down list
 *           parameter 2: id of the chosen item (0 ... number of options - 1)
 *           return LV_ACTION_RES_INV if the drop down list is deleted in the function else LV_ACTION_RES_OK
 */
void lv_ddlist_set_action(lv_obj_t * ddlist, lv_action_res_t (*cb)(lv_obj_t *, uint16_t))
{
    lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);
    ext->cb = cb;
}

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

/**
 * Get the options of a drop down list
 * @param ddlist pointer to drop down list object
 * @return the options separated by '\n'-s (E.g. "Option1\nOption2\nOption3")
 */
const char * lv_ddlist_get_options(lv_obj_t * ddlist)
{
    lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);
    return lv_label_get_text(ext->opt_label);
}

/**
 * Return with a pointer to a built-in style and/or copy it to a variable
 * @param style a style name from lv_ddlists_builtin_t enum
 * @param copy copy the style to this variable. (NULL if unused)
 * @return pointer to an lv_ddlists_t style
 */
lv_ddlists_t * lv_ddlists_get(lv_ddlists_builtin_t style, lv_ddlists_t * copy)
{
	static bool style_inited = false;

	/*Make the style initialization if it is not done yet*/
	if(style_inited == false) {
		lv_ddlists_init();
		style_inited = true;
	}

	lv_ddlists_t  *style_p;

	switch(style) {
		case LV_DDLISTS_DEF:
			style_p = &lv_ddlists_def;
			break;
		default:
			style_p = &lv_ddlists_def;
	}

	if(copy != NULL) {
		if(style_p != NULL) memcpy(copy, style_p, sizeof(lv_ddlists_t));
		else memcpy(copy, &lv_ddlists_def, sizeof(lv_ddlists_t));
	}

	return style_p;
}

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


/**
 * Handle the drawing related tasks of the drop down lists
 * @param ddlist pointer to an object
 * @param mask the object will be drawn only in this area
 * @param mode LV_DESIGN_COVER_CHK: only check if the object fully covers the 'mask_p' area
 *                                  (return 'true' if yes)
 *             LV_DESIGN_DRAW: draw the object (always return 'true')
 *             LV_DESIGN_DRAW_POST: drawing after every children are drawn
 * @param return true/false, depends on 'mode'
 */
static bool lv_ddlist_design(lv_obj_t * ddlist, const area_t * mask, lv_design_mode_t mode)
{
    /*Return false if the object is not covers the mask_p area*/
    if(mode == LV_DESIGN_COVER_CHK) {
    	return ancestor_design_f(ddlist, mask, mode);
    }
    /*Draw the object*/
    else if(mode == LV_DESIGN_DRAW_MAIN) {
        ancestor_design_f(ddlist, mask, mode);

        /*If the list is opened draw a rectangle below the selected item*/
        lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);
        if(ext->opened != 0) {
            lv_ddlists_t * style = lv_obj_get_style(ddlist);
            const font_t * font = font_get(style->list_labels.font);
            area_t rect_area;
            rect_area.y1 = ext->opt_label->cords.y1;
            rect_area.y1 += ext->act_opt * (font_get_height(font) + style->list_labels.line_space);
            rect_area.y1 -= style->sel_rects.vpad;

            rect_area.y2 = rect_area.y1 + font_get_height(font) + 2 * style->sel_rects.vpad;
            rect_area.x1 = ext->opt_label->cords.x1 - style->pages.scrl_rects.hpad;
            rect_area.x2 = rect_area.x1 + lv_obj_get_width(lv_page_get_scrl(ddlist));

            lv_draw_rect(&rect_area, mask, &style->sel_rects, OPA_COVER);
        }
    }
    /*Post draw when the children are drawn*/
    else if(mode == LV_DESIGN_DRAW_POST) {
        ancestor_design_f(ddlist, mask, mode);

    }

    return true;
}

/**
 * Called when a drop down list is released to open it or set new option
 * @param ddlist pointer to a drop down list object
 * @param dispi pointer to the called display input
 * @return LV_ACTION_RES_INV if the ddlist it deleted in the user callback else LV_ACTION_RES_OK
 */
static lv_action_res_t lv_ddlist_rel_action(lv_obj_t * ddlist, lv_dispi_t * dispi)
{
    lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);

    if(ext->opened == 0) { /*Open the list*/
        ext->opened = 1;
        lv_obj_set_drag(lv_page_get_scrl(ddlist), true);
    } else {
        ext->opened = 0;
        /*Search the clicked option*/
        point_t p;
        lv_dispi_get_point(dispi, &p);
        p.x -= ext->opt_label->cords.x1;
        p.y -= ext->opt_label->cords.y1;
        uint16_t letter_i;
        letter_i = lv_label_get_letter_on(ext->opt_label, &p);

        uint16_t new_opt = 0;
        const char * txt = lv_label_get_text(ext->opt_label);
        uint16_t i;
        for(i = 0; i < letter_i; i++) {
            if(txt[i] == '\n') new_opt ++;
        }

        ext->act_opt = new_opt;

        if(ext->cb != NULL) {
            ext->cb(ddlist, ext->act_opt);
        }
    }
#if LV_DDLIST_ANIM_TIME == 0
    lv_ddlist_refr_size(ddlist, false);
#else
    lv_ddlist_refr_size(ddlist, true);
#endif

    return LV_ACTION_RES_OK;

}

/**
 * Refresh the size of drop down list according its start (open or closed)
 * @param ddlist poinr to a drop down list object
 * @param anim_en true: refresh the size with an animation, false: do not use animations
 */
static void lv_ddlist_refr_size(lv_obj_t * ddlist, bool anim_en)
{
    lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);
    lv_ddlists_t * style = lv_obj_get_style(ddlist);
    cord_t new_height;
    if(ext->opened != 0) { /*Open the list*/
        new_height = lv_obj_get_height(lv_page_get_scrl(ddlist)) + 2 * style->pages.bg_rects.vpad;
        lv_obj_t * parent = lv_obj_get_parent(ddlist);
        if(new_height + ddlist->cords.y1 > parent->cords.y2) {
            new_height = parent->cords.y2 - ddlist->cords.y1;
        }
    } else { /*Close the list*/
        const font_t * font = font_get(style->list_labels.font);
        new_height = font_get_height(font) +  2 * style->sel_rects.vpad;
    }
    if(anim_en == false) {
        lv_obj_set_height(ddlist, new_height);
        lv_ddlist_pos_act_option(ddlist);
    } else {
        anim_t a;
        a.var = ddlist;
        a.start = lv_obj_get_height(ddlist);
        a.end = new_height;
        a.fp = (anim_fp_t)lv_obj_set_height;
        a.path = anim_get_path(ANIM_PATH_LIN);
        a.end_cb = (anim_cb_t)lv_ddlist_pos_act_option;
        a.act_time = 0;
        a.time = LV_DDLIST_ANIM_TIME;
        a.playback = 0;
        a.playback_pause = 0;
        a.repeat = 0;
        a.repeat_pause = 0;

        anim_create(&a);
    }
}

/**
 * Set the position of list when it is closed to show the selected item
 * @param ddlist pointer to a drop down list
 */
static void lv_ddlist_pos_act_option(lv_obj_t * ddlist)
{
    lv_ddlist_ext_t * ext = lv_obj_get_ext(ddlist);
    lv_ddlists_t * style = lv_obj_get_style(ddlist);
    const font_t * font = font_get(style->list_labels.font);

    lv_obj_set_y(lv_page_get_scrl(ddlist),
                       -(ext->act_opt * (font_get_height(font) + style->list_labels.line_space) +
                       style->pages.scrl_rects.vpad) + style->sel_rects.vpad);

}

/**
 * Initialize the built-in drop down list styles
 */
static void lv_ddlists_init(void)
{
	/*Default style*/
    lv_pages_get(LV_PAGES_SIMPLE, &lv_ddlists_def.pages);
    lv_ddlists_def.pages.bg_rects.objs.color = COLOR_WHITE;
    lv_ddlists_def.pages.bg_rects.gcolor = COLOR_SILVER;
    lv_ddlists_def.pages.bg_rects.bcolor = COLOR_GRAY;

    lv_ddlists_def.pages.bg_rects.hpad = 0 * LV_DOWNSCALE;
    lv_ddlists_def.pages.bg_rects.vpad = 0 * LV_DOWNSCALE;
    lv_ddlists_def.pages.bg_rects.opad = 0;

    lv_ddlists_def.pages.scrl_rects.hpad = 5 * LV_DOWNSCALE;
    lv_ddlists_def.pages.scrl_rects.vpad = 5 * LV_DOWNSCALE;
    lv_ddlists_def.pages.scrl_rects.opad = 0 * LV_DOWNSCALE;

    lv_ddlists_def.pages.sb_mode = LV_PAGE_SB_MODE_OFF;

    lv_labels_get(LV_LABELS_DEF, &lv_ddlists_def.list_labels);
    lv_ddlists_def.list_labels.line_space = 15 * LV_DOWNSCALE;

    lv_rects_get(LV_RECTS_DEF, &lv_ddlists_def.sel_rects);
    lv_ddlists_def.sel_rects.bwidth = 0;
    lv_ddlists_def.sel_rects.round = 0;
    lv_ddlists_def.sel_rects.vpad = 5 * LV_DOWNSCALE;
}

#endif