# lv_qrcode.h (/api/libs/qrcode/lv_qrcode_h)
Functions [#functions]
lv_qrcode_set_size [#lv_qrcode_set_size]
Set QR code size.
```c title=" " lineNumbers=1
void lv_qrcode_set_size(lv_obj_t *obj, int32_t size)
```
Parameters
| Name | Type | Description |
| ------ | ------------------------------------------------ | ------------------------------- |
| `obj` | | pointer to a QR code object |
| `size` | | width and height of the QR code |
lv_qrcode_set_dark_color [#lv_qrcode_set_dark_color]
Set QR code dark color.
```c title=" " lineNumbers=1
void lv_qrcode_set_dark_color(lv_obj_t *obj, lv_color_t color)
```
Parameters
| Name | Type | Description |
| ------- | ------------------------------------------------ | --------------------------- |
| `obj` | | pointer to a QR code object |
| `color` | | dark color of the QR code |
lv_qrcode_set_light_color [#lv_qrcode_set_light_color]
Set QR code light color.
```c title=" " lineNumbers=1
void lv_qrcode_set_light_color(lv_obj_t *obj, lv_color_t color)
```
Parameters
| Name | Type | Description |
| ------- | ------------------------------------------------ | --------------------------- |
| `obj` | | pointer to a QR code object |
| `color` | | light color of the QR code |
lv_qrcode_set_data [#lv_qrcode_set_data]
Helper function to set the data of a QR code object
```c title=" " lineNumbers=1
void lv_qrcode_set_data(lv_obj_t *obj, const char *data)
```
Parameters
| Name | Type | Description |
| ------ | ------------------------------------------------ | --------------------------- |
| `obj` | | pointer to a QR code object |
| `data` | `const char *` | data to display as a string |
lv_qrcode_set_quiet_zone [#lv_qrcode_set_quiet_zone]
Enable or disable quiet zone. Quiet zone is the area around the QR code where no data is encoded.
```c title=" " lineNumbers=1
void lv_qrcode_set_quiet_zone(lv_obj_t *obj, bool enable)
```
Parameters
| Name | Type | Description |
| -------- | ------------------------------------------------ | -------------------------------------------------- |
| `obj` | | pointer to a QR code object |
| `enable` | | true: enable quiet zone; false: disable quiet zone |
lv_qrcode_create [#lv_qrcode_create]
Create an empty QR code (an `lv_canvas`) object.
```c title=" " lineNumbers=1
lv_obj_t * lv_qrcode_create(lv_obj_t *parent)
```
Parameters
| Name | Type | Description |
| -------- | ------------------------------------------------ | ---------------------------------------------- |
| `parent` | | point to an object where to create the QR code |
**Returns:** — pointer to the created QR code object
lv_qrcode_update [#lv_qrcode_update]
Set the data of a QR code object
```c title=" " lineNumbers=1
lv_result_t lv_qrcode_update(lv_obj_t *obj, const void *data, uint32_t data_len)
```
Parameters
| Name | Type | Description |
| ---------- | ------------------------------------------------ | --------------------------- |
| `obj` | | pointer to a QR code object |
| `data` | `const void *` | data to display |
| `data_len` | | length of data in bytes |
**Returns:** — LV\_RESULT\_OK: if no error; LV\_RESULT\_INVALID: on error
Variables [#variables]
lv_qrcode_class [#lv_qrcode_class]
```c title=" " lineNumbers=1
const lv_obj_class_t lv_qrcode_class
```
Dependencies [#dependencies]