Single-line text-entry widget. More...

#include <text_entry.h>

Public Member Functions
	LcdGfxTextEntry (char buffer, uint8_t maxLen, const NanoRect &rect, const char charset=" ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.,!?-_")
	Creates a text-entry widget bound to the user's buffer. More...

void	up ()
	Cycles the character at the cursor forward through the charset.

void	down ()
	Cycles the character at the cursor backward through the charset.

void	left ()
	Moves the cursor one cell to the left, clamped at 0.

void	right ()
	Moves the cursor one cell to the right, clamped at maxLen - 1.

void	setCursor (uint8_t cursor)
	Sets the cursor position. More...

uint8_t	getCursor () const
	Returns the current cursor position.

const char *	getText () const
	Returns the underlying NUL-terminated text buffer.

uint8_t	getMaxLen () const
	Returns the maximum number of editable cells.

template<typename D >
void	show (D &d)
	Renders the widget to the display. More...

template<typename D >
void	updateSize (D &d)
	Auto-sizes the widget rectangle from the active font if a zero rect was supplied to the constructor.

const NanoRect &	getRect () const
	Returns the rectangle occupied by the widget.

Detailed Description

Single-line text-entry widget.

Typical embedded UX where the user moves a cursor along a fixed buffer and cycles the character at the cursor through a charset with up/down. The widget operates on a single-byte charset (ASCII by default); each cell holds exactly one byte. UTF-8 strings can still be displayed if the active font's secondary table covers the codepoints, but each cell is one byte — the charset itself must therefore be single-byte. The default charset is uppercase A-Z, digits and a few punctuation marks plus a leading space (used as the "blank" character).

Key bindings:

up() : cycle char at cursor forward through charset
down() : cycle char at cursor backward
left() : move cursor one cell left (clamped at 0)
right() : move cursor one cell right (clamped at maxLen-1)

Definition at line 60 of file text_entry.h.

Constructor & Destructor Documentation

◆ LcdGfxTextEntry()

LcdGfxTextEntry::LcdGfxTextEntry	(	char *	buffer,
		uint8_t	maxLen,
		const NanoRect &	rect,
		const char *	charset = `" ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.,!?-_"`
	)

Creates a text-entry widget bound to the user's buffer.

Parameters

buffer	user-owned NUL-terminated buffer to edit. Must have at least `maxLen` + 1 bytes available. On construction, every byte up to and including `maxLen` is initialised to charset[0] (the first character of the charset, which acts as the "blank" placeholder), then a NUL is written at offset `maxLen`.
maxLen	maximum number of editable cells (excludes the trailing NUL).
rect	screen area for the widget. Pass an empty rect to have show() auto-size from the active font.
charset	NUL-terminated single-byte charset. The first character is treated as the blank/space. Defaults to space + A-Z + 0-9 + a small punctuation block.

Member Function Documentation

◆ setCursor()

void LcdGfxTextEntry::setCursor ( uint8_t cursor )

Sets the cursor position.

Clamped to [0, maxLen - 1].

◆ show()

template<typename D >

void LcdGfxTextEntry::show ( D & d )

inline

Renders the widget to the display.

Draws the buffer left-to-right inside the widget rectangle and underlines the cursor cell so the user can see which cell is being edited.