Spinbox (lv_spinbox)¶

Overview¶

The Spinbox contains a number as text which can be increased or decreased by Keys or API functions. Under the hood the Spinbox is a modified Text area.

Parts and Styles¶

The parts of the Spinbox are identical to the Text area.

Value, range and step¶

lv_spinbox_set_value(spinbox, 1234) sets a new value on the Spinbox.

lv_spinbox_increment(spinbox) and lv_spinbox_decrement(spinbox) increments/decrements the value of the Spinbox according to the currently selected digit.

lv_spinbox_set_range(spinbox, -1000, 2500) sets a range. If the value is changed by lv_spinbox_set_value, by Keys,lv_spinbox_increment/decrement this range will be respected.

lv_spinbox_set_step(spinbox, 100) sets which digits to change on increment/decrement. Only multiples of ten can be set, and not for example 3.

lv_spinbox_set_cursor_pos(spinbox, 1) sets the cursor to a specific digit to change on increment/decrement. For example position '0' sets the cursor to the least significant digit.

If an encoder is used as input device, the selected digit is shifted to the right by default whenever the encoder button is clicked. To change this behaviour to shifting to the left, the lv_spinbox_set_digit_step_direction(spinbox, LV_DIR_LEFT) can be used

Format¶

lv_spinbox_set_digit_format(spinbox, digit_count, separator_position) sets the number format. digit_count is the number of digits excluding the decimal separator and the sign. separator_position is the number of digits before the decimal point. If 0, no decimal point is displayed.

Rollover¶

lv_spinbox_set_rollover(spinbox, true/false) enables/disabled rollover mode. If either the minimum or maximum value is reached with rollover enabled, the value will change to the other limit. If rollover is disabled the value will remain at the minimum or maximum value.

Events¶

LV_EVENT_VALUE_CHANGED Sent when the value has changed.

See the events of the Text area too.

Learn more about Events.

Keys¶

LV_KEY_LEFT/RIGHT With Keypad move the cursor left/right. With Encoder decrement/increment the selected digit.
LV_KEY_UP/DOWN With Keypad and Encoder increment/decrement the value.
LV_KEY_ENTER With Encoder got the next digit. Jump to the first after the last.

Example¶

Simple Spinbox¶

#include "../../lv_examples.h"
#if LV_USE_SPINBOX && LV_BUILD_EXAMPLES

static lv_obj_t * spinbox;

static void lv_spinbox_increment_event_cb(lv_event_t * e)
{
    lv_event_code_t code = lv_event_get_code(e);
    if(code == LV_EVENT_SHORT_CLICKED || code  == LV_EVENT_LONG_PRESSED_REPEAT) {
        lv_spinbox_increment(spinbox);
    }
}

static void lv_spinbox_decrement_event_cb(lv_event_t * e)
{
    lv_event_code_t code = lv_event_get_code(e);
    if(code == LV_EVENT_SHORT_CLICKED || code == LV_EVENT_LONG_PRESSED_REPEAT) {
        lv_spinbox_decrement(spinbox);
    }
}

void lv_example_spinbox_1(void)
{
    spinbox = lv_spinbox_create(lv_scr_act());
    lv_spinbox_set_range(spinbox, -1000, 25000);
    lv_spinbox_set_digit_format(spinbox, 5, 2);
    lv_spinbox_step_prev(spinbox);
    lv_obj_set_width(spinbox, 100);
    lv_obj_center(spinbox);

    lv_coord_t h = lv_obj_get_height(spinbox);

    lv_obj_t * btn = lv_btn_create(lv_scr_act());
    lv_obj_set_size(btn, h, h);
    lv_obj_align_to(btn, spinbox, LV_ALIGN_OUT_RIGHT_MID, 5, 0);
    lv_obj_set_style_bg_img_src(btn, LV_SYMBOL_PLUS, 0);
    lv_obj_add_event_cb(btn, lv_spinbox_increment_event_cb, LV_EVENT_ALL,  NULL);

    btn = lv_btn_create(lv_scr_act());
    lv_obj_set_size(btn, h, h);
    lv_obj_align_to(btn, spinbox, LV_ALIGN_OUT_LEFT_MID, -5, 0);
    lv_obj_set_style_bg_img_src(btn, LV_SYMBOL_MINUS, 0);
    lv_obj_add_event_cb(btn, lv_spinbox_decrement_event_cb, LV_EVENT_ALL, NULL);
}

#endif

def increment_event_cb(e):
    code = e.get_code()
    if code == lv.EVENT.SHORT_CLICKED or code  == lv.EVENT.LONG_PRESSED_REPEAT:
        spinbox.increment()

def decrement_event_cb(e):
    code = e.get_code()
    if code == lv.EVENT.SHORT_CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
        spinbox.decrement()

spinbox = lv.spinbox(lv.scr_act())
spinbox.set_range(-1000, 25000)
spinbox.set_digit_format(5, 2)
spinbox.step_prev()
spinbox.set_width(100)
spinbox.center()

h = spinbox.get_height()

btn = lv.btn(lv.scr_act())
btn.set_size(h, h)
btn.align_to(spinbox, lv.ALIGN.OUT_RIGHT_MID, 5, 0)
btn.set_style_bg_img_src(lv.SYMBOL.PLUS, 0)
btn.add_event_cb(increment_event_cb, lv.EVENT.ALL,  None)

btn = lv.btn(lv.scr_act())
btn.set_size(h, h)
btn.align_to(spinbox, lv.ALIGN.OUT_LEFT_MID, -5, 0)
btn.set_style_bg_img_src(lv.SYMBOL.MINUS, 0)
btn.add_event_cb(decrement_event_cb, lv.EVENT.ALL, None)

API¶

Functions

lv_obj_t *lv_spinbox_create(lv_obj_t *parent)¶

Create a Spinbox object

Parameters: parent -- pointer to an object, it will be the parent of the new spinbox
Returns: pointer to the created spinbox

void lv_spinbox_set_value(lv_obj_t *obj, int32_t i)¶

Set spinbox value

Parameters

obj -- pointer to spinbox
i -- value to be set

void lv_spinbox_set_rollover(lv_obj_t *obj, bool b)¶

Set spinbox rollover function

Parameters

obj -- pointer to spinbox
b -- true or false to enable or disable (default)

void lv_spinbox_set_digit_format(lv_obj_t *obj, uint8_t digit_count, uint8_t separator_position)¶

Set spinbox digit format (digit count and decimal format)

Parameters

obj -- pointer to spinbox
digit_count -- number of digit excluding the decimal separator and the sign
separator_position -- number of digit before the decimal point. If 0, decimal point is not shown

void lv_spinbox_set_step(lv_obj_t *obj, uint32_t step)¶

Set spinbox step

Parameters

obj -- pointer to spinbox
step -- steps on increment/decrement. Can be 1, 10, 100, 1000, etc the digit that will change.

void lv_spinbox_set_range(lv_obj_t *obj, int32_t range_min, int32_t range_max)¶

Set spinbox value range

Parameters

obj -- pointer to spinbox
range_min -- maximum value, inclusive
range_max -- minimum value, inclusive

void lv_spinbox_set_cursor_pos(lv_obj_t *obj, uint8_t pos)¶

Set cursor position to a specific digit for edition

Parameters

obj -- pointer to spinbox
pos -- selected position in spinbox

void lv_spinbox_set_digit_step_direction(lv_obj_t *obj, lv_dir_t direction)¶

Set direction of digit step when clicking an encoder button while in editing mode

Parameters

obj -- pointer to spinbox
direction -- the direction (LV_DIR_RIGHT or LV_DIR_LEFT)

bool lv_spinbox_get_rollover(lv_obj_t *obj)¶

Get spinbox rollover function status

Parameters: obj -- pointer to spinbox

int32_t lv_spinbox_get_value(lv_obj_t *obj)¶

Get the spinbox numeral value (user has to convert to float according to its digit format)

Parameters: obj -- pointer to spinbox
Returns: value integer value of the spinbox

int32_t lv_spinbox_get_step(lv_obj_t *obj)¶

Get the spinbox step value (user has to convert to float according to its digit format)

Parameters: obj -- pointer to spinbox
Returns: value integer step value of the spinbox

void lv_spinbox_step_next(lv_obj_t *obj)¶

Select next lower digit for edition by dividing the step by 10

Parameters: obj -- pointer to spinbox

void lv_spinbox_step_prev(lv_obj_t *obj)¶

Select next higher digit for edition by multiplying the step by 10

Parameters: obj -- pointer to spinbox

void lv_spinbox_increment(lv_obj_t *obj)¶

Increment spinbox value by one step

Parameters: obj -- pointer to spinbox

void lv_spinbox_decrement(lv_obj_t *obj)¶

Decrement spinbox value by one step

Parameters: obj -- pointer to spinbox

Variables

const lv_obj_class_t lv_spinbox_class¶

struct lv_spinbox_t¶

Public Members

lv_textarea_t ta¶

int32_t value¶

int32_t range_max¶

int32_t range_min¶

int32_t step¶

uint16_t digit_count¶

uint16_t dec_point_pos¶

uint16_t rollover¶

uint16_t digit_step_dir¶