lv_txt.h

Defines

LV_TXT_ENC_UTF8
LV_TXT_ENC_ASCII

Typedefs

typedef _lv_text_flag_t lv_text_flag_t
typedef _lv_text_cmd_state_t lv_text_cmd_state_t
typedef _lv_text_align_t lv_text_align_t

Enums

enum _lv_text_flag_t

Options for text rendering.

Values:

enumerator LV_TEXT_FLAG_NONE
enumerator LV_TEXT_FLAG_RECOLOR

Enable parsing of recolor command

enumerator LV_TEXT_FLAG_EXPAND

Ignore max-width to avoid automatic word wrapping

enumerator LV_TEXT_FLAG_FIT

Max-width is already equal to the longest line. (Used to skip some calculation)

enum _lv_text_cmd_state_t

State machine for text renderer.

Values:

enumerator LV_TEXT_CMD_STATE_WAIT

Waiting for command

enumerator LV_TEXT_CMD_STATE_PAR

Processing the parameter

enumerator LV_TEXT_CMD_STATE_IN

Processing the command

enum _lv_text_align_t

Label align policy

Values:

enumerator LV_TEXT_ALIGN_AUTO

Align text auto

enumerator LV_TEXT_ALIGN_LEFT

Align text to left

enumerator LV_TEXT_ALIGN_CENTER

Align text to center

enumerator LV_TEXT_ALIGN_RIGHT

Align text to right

Functions

void lv_txt_get_size(lv_point_t *size_res, const char *text, const lv_font_t *font, lv_coord_t letter_space, lv_coord_t line_space, lv_coord_t max_width, lv_text_flag_t flag)

Get size of a text

line breaks

Parameters:
  • size_res -- pointer to a 'point_t' variable to store the result

  • text -- pointer to a text

  • font -- pointer to font of the text

  • letter_space -- letter space of the text

  • line_space -- line space of the text

  • max_width -- max width of the text (break the lines to fit this size). Set COORD_MAX to avoid

  • flag -- settings for the text from ::lv_text_flag_t

uint32_t _lv_txt_get_next_line(const char *txt, const lv_font_t *font, lv_coord_t letter_space, lv_coord_t max_width, lv_coord_t *used_width, lv_text_flag_t flag)

Get the next line of text. Check line length and break chars too.

Parameters:
  • txt -- a '\0' terminated string

  • font -- pointer to a font

  • letter_space -- letter space

  • max_width -- max width of the text (break the lines to fit this size). Set COORD_MAX to avoid line breaks

  • used_width -- When used_width != NULL, save the width of this line if flag == LV_TEXT_FLAG_NONE, otherwise save -1.

  • flag -- settings for the text from 'txt_flag_type' enum

Returns:

the index of the first char of the new line (in byte index not letter index. With UTF-8 they are different)

lv_coord_t lv_txt_get_width(const char *txt, uint32_t length, const lv_font_t *font, lv_coord_t letter_space, lv_text_flag_t flag)

Give the length of a text with a given font

Parameters:
  • txt -- a '\0' terminate string

  • length -- length of 'txt' in byte count and not characters (Á is 1 character but 2 bytes in UTF-8)

  • font -- pointer to a font

  • letter_space -- letter space

  • flag -- settings for the text from 'txt_flag_t' enum

Returns:

length of a char_num long text

bool _lv_txt_is_cmd(lv_text_cmd_state_t *state, uint32_t c)

Check next character in a string and decide if the character is part of the command or not

Parameters:
  • state -- pointer to a txt_cmd_state_t variable which stores the current state of command processing

  • c -- the current character

Returns:

true: the character is part of a command and should not be written, false: the character should be written

void _lv_txt_ins(char *txt_buf, uint32_t pos, const char *ins_txt)

Insert a string into an other

Parameters:
  • txt_buf -- the original text (must be big enough for the result text and NULL terminated)

  • pos -- position to insert (0: before the original text, 1: after the first char etc.)

  • ins_txt -- text to insert, must be '\0' terminated

void _lv_txt_cut(char *txt, uint32_t pos, uint32_t len)

Delete a part of a string

Parameters:
  • txt -- string to modify, must be '\0' terminated and should point to a heap or stack frame, not read-only memory.

  • pos -- position where to start the deleting (0: before the first char, 1: after the first char etc.)

  • len -- number of characters to delete

char *_lv_txt_set_text_vfmt(const char *fmt, va_list ap)

return a new formatted text. Memory will be allocated to store the text.

Parameters:
  • fmt -- printf-like format

  • ap -- items to print

Returns:

pointer to the allocated text string.

void _lv_txt_encoded_letter_next_2(const char *txt, uint32_t *letter, uint32_t *letter_next, uint32_t *ofs)

Decode two encoded character from a string.

Parameters:
  • txt -- pointer to '\0' terminated string

  • letter -- the first decoded Unicode character or 0 on invalid data code

  • letter_next -- the second decoded Unicode character or 0 on invalid data code

  • ofs -- start index in 'txt' where to start. After the call it will point to the next encoded char in 'txt'. NULL to use txt[0] as index

static inline bool _lv_txt_is_break_char(uint32_t letter)

Test if char is break char or not (a text can broken here or not)

Parameters:

letter -- a letter

Returns:

false: 'letter' is not break char

static inline bool _lv_txt_is_a_word(uint32_t letter)

Test if char is break char or not (a text can broken here or not)

Parameters:

letter -- a letter

Returns:

false: 'letter' is not break char

Variables

uint8_t (*_lv_txt_encoded_size)(const char*)

Give the size of an encoded character

Param str:

pointer to a character in a string

Return:

length of the encoded character (1,2,3 ...). O in invalid

uint32_t (*_lv_txt_unicode_to_encoded)(uint32_t)

Convert a Unicode letter to encoded

Param letter_uni:

a Unicode letter

Return:

Encoded character in Little Endian to be compatible with C chars (e.g. 'Á', 'Ü')

uint32_t (*_lv_txt_encoded_conv_wc)(uint32_t c)

Convert a wide character, e.g. 'Á' little endian to be compatible with the encoded format.

Param c:

a wide character

Return:

c in the encoded format

uint32_t (*_lv_txt_encoded_next)(const char*, uint32_t*)

Decode the next encoded character from a string.

Param txt:

pointer to '\0' terminated string

Param i:

start index in 'txt' where to start. After the call it will point to the next encoded char in 'txt'. NULL to use txt[0] as index

Return:

the decoded Unicode character or 0 on invalid data code

uint32_t (*_lv_txt_encoded_prev)(const char*, uint32_t*)

Get the previous encoded character form a string.

Param txt:

pointer to '\0' terminated string

Param i_start:

index in 'txt' where to start. After the call it will point to the previous encoded char in 'txt'.

Return:

the decoded Unicode character or 0 on invalid data

uint32_t (*_lv_txt_encoded_get_byte_id)(const char*, uint32_t)

Convert a letter index (in the encoded text) to byte index. E.g. in UTF-8 "AÁRT" index of 'R' is 2 but start at byte 3 because 'Á' is 2 bytes long

Param txt:

a '\0' terminated UTF-8 string

Param enc_id:

letter index

Return:

byte index of the 'enc_id'th letter

uint32_t (*_lv_txt_encoded_get_char_id)(const char*, uint32_t)

Convert a byte index (in an encoded text) to character index. E.g. in UTF-8 "AÁRT" index of 'R' is 2 but start at byte 3 because 'Á' is 2 bytes long

Param txt:

a '\0' terminated UTF-8 string

Param byte_id:

byte index

Return:

character index of the letter at 'byte_id'th position

uint32_t (*_lv_txt_get_encoded_length)(const char*)

Get the number of characters (and NOT bytes) in a string. E.g. in UTF-8 "ÁBC" is 3 characters (but 4 bytes)

Param txt:

a '\0' terminated char string

Return:

number of characters