# lv_barcode.h (/api/public/widgets/lv_barcode_h)
Functions [#functions]
lv_barcode_set_dark_color [#lv_barcode_set_dark_color]
Set the dark color of a barcode object. Only rewrites the palette, so it takes effect before or after the data and never regenerates the bars.
```c title=" " lineNumbers=1
void lv_barcode_set_dark_color(lv_obj_t *obj, lv_color_t color)
```
Parameters
| Name | Type | Description |
| ------- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
| `color` | | dark color of the barcode |
lv_barcode_set_light_color [#lv_barcode_set_light_color]
Set the light color of a barcode object. Only rewrites the palette, so it takes effect before or after the data and never regenerates the bars.
```c title=" " lineNumbers=1
void lv_barcode_set_light_color(lv_obj_t *obj, lv_color_t color)
```
Parameters
| Name | Type | Description |
| ------- | ------------------------------------------------ | -------------------------- |
| `obj` | | pointer to barcode object |
| `color` | | light color of the barcode |
lv_barcode_set_scale [#lv_barcode_set_scale]
Set the scale of a barcode object, i.e. the pixel width of a single bar. The stored data is re-generated, so this may be called before or after the data.
```c title=" " lineNumbers=1
void lv_barcode_set_scale(lv_obj_t *obj, uint16_t scale)
```
Parameters
| Name | Type | Description |
| ------- | ------------------------------------------------ | -------------------------------- |
| `obj` | | pointer to barcode object |
| `scale` | `uint16_t` | scale factor; must be at least 1 |
lv_barcode_set_direction [#lv_barcode_set_direction]
Set the direction of a barcode object. The stored data is re-generated, so this may be called before or after the data.
```c title=" " lineNumbers=1
void lv_barcode_set_direction(lv_obj_t *obj, lv_dir_t direction)
```
Parameters
| Name | Type | Description |
| ----------- | ------------------------------------------------ | --------------------------------------------- |
| `obj` | | pointer to barcode object |
| `direction` | | draw direction (`LV_DIR_HOR` or `LV_DIR_VER`) |
lv_barcode_set_tiled [#lv_barcode_set_tiled]
Set the tiled mode of a barcode object. The stored data is re-generated, so this may be called before or after the data.
```c title=" " lineNumbers=1
void lv_barcode_set_tiled(lv_obj_t *obj, bool tiled)
```
Parameters
| Name | Type | Description |
| ------- | ------------------------------------------------ | ---------------------------------------------- |
| `obj` | | pointer to barcode object |
| `tiled` | `bool` | true: tiled mode, false: normal mode (default) |
lv_barcode_set_encoding [#lv_barcode_set_encoding]
Set the encoding of a barcode object. The stored data is re-generated, so this may be called before or after the data.
```c title=" " lineNumbers=1
void lv_barcode_set_encoding(lv_obj_t *obj, lv_barcode_encoding_t encoding)
```
Parameters
| Name | Type | Description |
| ---------- | ------------------------------------------------ | ------------------------------------------------------- |
| `obj` | | pointer to barcode object |
| `encoding` | | encoding (default is `LV_BARCODE_ENCODING_CODE128_GS1`) |
lv_barcode_set_update_mode [#lv_barcode_set_update_mode]
Set when a change is turned into a new barcode bitmap. Applies to the data and to the scale, direction, tiled mode and encoding; the colors are never affected.
```c title=" " lineNumbers=1
void lv_barcode_set_update_mode(lv_obj_t *obj, lv_barcode_update_mode_t mode)
```
Parameters
| Name | Type | Description |
| ------ | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
| `mode` | | the mode to use |
Only the fill is deferred. The canvas is resized in the setter in both modes, because the draw pass cannot reallocate it.
Deferred mode expects an explicit , which returns the result. Forgetting it still gives the right bitmap, but the redraw does the work and warns, and no caller is left to see a failure.
Switching back to IMMEDIATE while out of date also regenerates, but this returns void, so a failure is only logged. Render first to get the result.
lv_barcode_get_update_mode [#lv_barcode_get_update_mode]
Get when a property change is turned into a new barcode bitmap.
```c title=" " lineNumbers=1
lv_barcode_update_mode_t lv_barcode_get_update_mode(lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** — the update mode currently in use
lv_barcode_get_dark_color [#lv_barcode_get_dark_color]
Get the dark color of a barcode object
```c title=" " lineNumbers=1
lv_color_t lv_barcode_get_dark_color(lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** — dark color of the barcode
lv_barcode_get_light_color [#lv_barcode_get_light_color]
Get the light color of a barcode object
```c title=" " lineNumbers=1
lv_color_t lv_barcode_get_light_color(lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** — light color of the barcode
lv_barcode_get_scale [#lv_barcode_get_scale]
Get the scale of a barcode object
```c title=" " lineNumbers=1
uint16_t lv_barcode_get_scale(lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** `uint16_t` — scale factor
lv_barcode_get_encoding [#lv_barcode_get_encoding]
Get the encoding of a barcode object
```c title=" " lineNumbers=1
lv_barcode_encoding_t lv_barcode_get_encoding(const lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** — encoding
lv_barcode_create [#lv_barcode_create]
Create an empty barcode (an `lv_canvas`) object.
```c title=" " lineNumbers=1
lv_obj_t * lv_barcode_create(lv_obj_t *parent)
```
Parameters
| Name | Type | Description |
| -------- | ------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------ |
| `parent` | | pointer to a parent widget **May** be `NULL`.. When NULL, the widget is created as a screen on the active display. |
**Returns:** — pointer to the created barcode object
lv_barcode_update [#lv_barcode_update]
Set the data of a barcode object and generate the bitmap. A copy is stored, so a later property change or resize can regenerate it; the properties may be set before or after the data, in any order.
```c title=" " lineNumbers=1
lv_result_t lv_barcode_update(lv_obj_t *obj, const char *data)
```
Parameters
| Name | Type | Description |
| ------ | ------------------------------------------------ | ------------------------------------------ |
| `obj` | | pointer to barcode object |
| `data` | `const char *` | data to display as a NUL terminated string |
**Returns:** — LV\_RESULT\_OK: if no error; LV\_RESULT\_INVALID: on error
Obeys the update mode. In DEFERRED the canvas is only resized here, so the return value reports that resize, not the bars.
lv_barcode_render [#lv_barcode_render]
(Re)generate the barcode bitmap from the stored data, whether or not anything changed. Needs no data argument, which is how deferred changes are applied.
```c title=" " lineNumbers=1
lv_result_t lv_barcode_render(lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** — LV\_RESULT\_OK: if no error; LV\_RESULT\_INVALID: on error (e.g. no data set, or the bars do not fit the current object size)
lv_barcode_is_render_valid [#lv_barcode_is_render_valid]
Check whether the bitmap is free of a known generation failure. , and in IMMEDIATE mode, return their result directly; the rest cannot - they run in a void setter, the resize handler, or a deferred fill in the draw pass. Use this for those, e.g. after shrinking the object below the size its data needs.
```c title=" " lineNumbers=1
bool lv_barcode_is_render_valid(lv_obj_t *obj)
```
Parameters
| Name | Type | Description |
| ----- | ------------------------------------------------ | ------------------------- |
| `obj` | | pointer to barcode object |
**Returns:** `bool` — true: no generation attempt is known to have failed. A change re-arms the Widget, so this is also true while a deferred regeneration is still pending; false: the last generation attempt failed, or no data has been set yet
A failure is not retried every redraw; only a change makes the Widget try again.
Enums [#enums]
lv_barcode_encoding_t [#lv_barcode_encoding_t]
| Name | Description |
| --------------------------------- | ------------------------------------------------------- |
| `LV_BARCODE_ENCODING_CODE128_GS1` | Code 128 with GS1 encoding. Strips `[FCN1]` and spaces. |
| `LV_BARCODE_ENCODING_CODE128_RAW` | Code 128 with raw encoding. |
* `lv_barcode_set_encoding` — param `encoding`
lv_barcode_update_mode_t [#lv_barcode_update_mode_t]
Controls when a change is turned into a new barcode bitmap. Applies to the data too. The colors are always a palette-only write, so they are never affected.
| Name | Value | Description |
| ---------------------------------- | ----- | ------------------------------------------------------------------------- |
| `LV_BARCODE_UPDATE_MODE_IMMEDIATE` | `0` | Re-generate as soon as a property changes (default) |
| `LV_BARCODE_UPDATE_MODE_DEFERRED` | | Only mark the bitmap out of date and re-generate once, on the next redraw |
* `lv_barcode_set_update_mode` — param `mode`
Variables [#variables]
lv_barcode_class [#lv_barcode_class]
```c title=" " lineNumbers=1
const lv_obj_class_t lv_barcode_class
```
Dependencies [#dependencies]