CharacterDisplayRenderer

class CharacterDisplayRenderer : public MenuRenderer
#include <CharacterDisplayRenderer.h>

A renderer for character-based displays, extending the MenuRenderer class.

This class provides functionality to render menus on character-based displays. It supports custom icons for cursor and edit cursor, as well as up and down arrows for navigation indicators.

The CharacterDisplayRenderer class is designed to work with displays that implement the CharacterDisplayInterface. It provides methods to draw menu items, cursors, and navigation indicators. The class also handles text truncation and cursor movement.

Note

The class uses dynamic memory allocation for the upArrow and downArrow icons.

Public Functions

CharacterDisplayRenderer(CharacterDisplayInterface *display, const uint8_t maxCols, const uint8_t maxRows, const uint8_t cursorIcon = 0x7E, const uint8_t editCursorIcon = 0x7F, uint8_t *upArrow = new uint8_t[8]{0x04, 0x0E, 0x1F, 0x04, 0x04, 0x04, 0x04, 0x04}, uint8_t *downArrow = new uint8_t[8]{0x04, 0x04, 0x04, 0x04, 0x04, 0x1F, 0x0E, 0x04})

Constructor for CharacterDisplayRenderer. Initializes the renderer with the display, maximum columns, and maximum rows. Also sets the up and down arrow icons, cursor icons, and edit cursor icons.

Note

slots 1 and 2 are reserved for up and down arrow icons. The available custom characters slots are 0 and 3 to 7.

Parameters:

  • display – A pointer to the CharacterDisplayInterface object.

  • maxCols – The maximum number of columns on the display.

  • maxRows – The maximum number of rows on the display.

  • cursorIcon – A byte representing the cursor icon, default is →, if 0, cursor will not be displayed

  • editCursorIcon – A byte representing the edit cursor icon, default is ←, if 0, edit cursor will not be displayed

  • upArrow – A pointer to an array of bytes representing the up arrow icon, default is ↑, if null, up arrow will not be displayed

  • downArrow – A pointer to an array of bytes representing the down arrow icon, default is ↓, if null, down arrow will not be displayed

virtual void begin() override

Initializes the renderer and creates custom characters on the display.

virtual void drawItem(const char *text, const char *value) override

Draws a menu item on the character display.

This function overrides the base class implementation to draw a menu item on the character display. It handles appending a cursor to the text, truncating the text if it’s too long, padding the text with spaces, appending an indicator to the text, and finally drawing the text on the display.

Parameters:

  • text – The text of the menu item to be drawn.

  • value – The value of the menu item to be drawn.

virtual void draw(uint8_t byte) override

Function to draw a byte on the display.

Parameters:

byte – The byte to be drawn.

virtual void drawBlinker() override

Function to draw the blinker on the display.

virtual void clearBlinker() override

Function to clear the blinker from the display.

virtual void moveCursor(uint8_t cursorCol, uint8_t cursorRow) override

Moves the cursor to a specified position.

Parameters:

  • cursorCol – Column position to move the cursor to.

  • cursorRow – Row position to move the cursor to.

Protected Functions

void appendCursorToText(char *text)

Appends a cursor icon to the given text if the specified screen row is active.

Parameters:

text – The original text to which the cursor icon will be appended.

void appendIndicatorToText(char *text)

Appends an indicator to the provided text based on the item index and screen row.

Parameters:

text – The original text to which the indicator may be appended.

void padText(char *text)

Pads the given text with spaces to fit within the available length.

This function takes a text string and pads it with spaces so that the total length of the text fits within the available length of the display. If the text is longer than the available length, no padding is added.

Parameters:

text – The input text to be padded.

virtual uint8_t getEffectiveCols() const override

Calculates the available horizontal space for displaying content.

This function computes the number of columns available for displaying content on the display. It takes into account the presence of up and down arrows, which occupy one column if either is present.

Returns:

The number of columns available for displaying content.

Protected Attributes

uint8_t *upArrow
uint8_t *downArrow
const uint8_t cursorIcon
const uint8_t editCursorIcon
const uint8_t availableColumns