How to use lv_chart_set_ext_y_array on lv_chart graph?

Ibrahim_Aydin · April 15, 2022, 11:09am

Description

I want to draw a graph like this. However, when I use LVGL lv_chart_set_ext_y_array function, I only get a colum line. But what I want is a field contains of lines like this.

Ekran görüntüsü 2022-04-15 115550

What MCU/Processor/Board and compiler are you using?

STM32F407VE + 3.2" ILI9341 TFT LCD

What LVGL version are you using?

8.2

What do you want to achieve?

What have you tried so far?

I tried this code

Code to reproduce

The code:

lv_coord_t i=0, j=0, p=0;

__IO uint32_t msNow = 0 , msLast = 0;
lv_disp_t * disp;
__IO uint32_t k=0;
__IO uint8_t toplam=0;

lv_coord_t arr_t[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63};
extern lv_coord_t xCoords[pointCount];
extern lv_coord_t arrPoints[pointCount];
extern __IO int8_t flagDrawPointsDone;

uint16_t x=0;

static void add_data(lv_timer_t * timer)
{
    LV_UNUSED(timer);

    ser2->x_points=xCoords;
	for(uint8_t i=0; i<pointCount;i++)
	{
		arrPoints[i]=(lv_coord_t)i;
		xCoords[i]=xnow;
	}
    lv_chart_set_ext_y_array(chart1, ser2, (lv_coord_t *) arrPoints);

}

///////////////////// SCREENS ////////////////////
void ui_Screen1_screen_init(void)
{

    /*Create a chart1*/
    chart1 = lv_chart_create(lv_scr_act());
    lv_chart_set_point_count(chart1, pointCount);
    lv_obj_set_size(chart1, 290, 210);
    lv_obj_align(chart1, LV_ALIGN_CENTER, 15, 13);
    lv_obj_set_style_size(chart1, 2, LV_PART_INDICATOR);
    lv_chart_set_type(chart1, LV_CHART_TYPE_SCATTER);
    lv_chart_set_range(chart1, LV_CHART_AXIS_PRIMARY_Y, 0, 64);
    lv_chart_set_range(chart1, LV_CHART_AXIS_PRIMARY_X, 0, 100);
    lv_obj_set_style_bg_color(chart1, lv_color_make(0,0,0), 0);
    lv_obj_add_event_cb(chart1, draw_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
    lv_chart_set_update_mode(chart1, LV_CHART_UPDATE_MODE_SHIFT);
    lv_chart_set_axis_tick(chart1, LV_CHART_AXIS_PRIMARY_Y, 0, 10, 6, 1, true, 50);
    lv_obj_set_style_line_width(chart1, 0, LV_PART_ITEMS);

    /*Add two data series*/
    ser1 = lv_chart_add_series(chart1, lv_color_hex(0x0000FF), LV_CHART_AXIS_PRIMARY_Y);
    ser2 = lv_chart_add_series(chart1, lv_color_hex(0xFF0000), LV_CHART_AXIS_PRIMARY_Y);

    lv_obj_t * label = lv_label_create(lv_scr_act());
    lv_label_set_recolor(label, true);
    lv_label_set_text(label, "#000000 ADC DATA GRAPH#");
    lv_obj_align_to(label, chart1, LV_ALIGN_OUT_TOP_MID, 0, -2);
    lv_obj_set_width(label, 200);

    lv_timer_create(add_data, 5, chart1);
}

void ui_init(void)
{
    ui_Screen1_screen_init();
    lv_disp_load_scr(ui_Screen1);
}