keyboard.h File Reference

nds stdio keyboard integration. More...

#include <nds/ndstypes.h>
#include <nds/arm9/background.h>

Data Structures
struct	Keyboard
	describes a keyboard. More...
struct	KeyMap
	defines a key mapping. More...

Typedefs
typedef struct Keyboard	Keyboard
	describes a keyboard.
typedef void(*	KeyChangeCallback) (int key)
	callback function pointer for a key changed.
typedef struct KeyMap	KeyMap
	defines a key mapping.

Enumerations

Functions
Keyboard *	keyboardDemoInit (void)
	initializes the keyboard with default options. Same as calling keyboardInit(NULL, 3, BgType_Text4bpp, BgSize_T_256x512, 20, 0, false, true) More...
int	keyboardGetChar (void)
	Waits for user to press a key and returns the key pressed. Use keyboardUpdate instead for async operation.
Keyboard *	keyboardGetDefault (void)
	Gets the default keyboard.
int	keyboardGetKey (int x, int y)
	returns the ascii code for the key located at the supplied x and y. Will not effect keyboard shift state. More...
void	keyboardGetString (char *buffer, int maxLen)
	reads the input until a the return key is pressed or the maxLen is exceeded. More...
void	keyboardHide (void)
	Hides the keyboard.
Keyboard *	keyboardInit (Keyboard *keyboard, int layer, BgType type, BgSize size, int mapBase, int tileBase, bool mainDisplay, bool loadGraphics)
	initializes the keyboard system with the supplied keyboard More...
void	keyboardShow (void)
	Displays the keyboard.
int	keyboardUpdate (void)
	Processes the keyboard. Should be called once per frame when using the keyboard in an async manner. More...

Detailed Description

nds stdio keyboard integration.

The keyboard component allows the use of a default keyboard via stdin as well as direct via the functions exposed below. The default behavior is a hidden keyboard that shows on a call to scanf(stdin, ...).

By default the keyboard uses background 3 of the sub display, consumes approximatly 40KiB of background vram begining at tile base 1 and 2KB of map stored at map base 30. The default is designed to function along side a default instance of the console print functionality.

To customize keyboard behavior and resource usage modify the keyboard structure returned by keyboardGetDefault() or create your own keyboard.

Enumeration Type Documentation

enum KeyboardState

States the keyboard can be in, currently only Lower and Upper supported.

Enumerator
Lower	Normal keyboard display (lowercase letters)
Upper	Caps lock Held
Numeric	Numeric only keypad (not provided by the default keyboard)
Reduced	Reduced footprint keyboard (not provided by the default keyboard)

enum Keys

enum values for the keyboard control keys. negative values are keys with no sensible ascii representation. numbers are chosen to mimic ascii control sequences.

Enumerator
NOKEY	will be returned if no key was pressed.
DVK_FOLD	will be returned if the fold key was pressed (topleft on the default keyboard).
DVK_TAB	will be returned if the tab key was pressed.
DVK_BACKSPACE	will be returned if the backspace key was pressed.
DVK_CAPS	will be returned if the caps key was pressed.
DVK_SHIFT	will be returned if the shift key was pressed.
DVK_SPACE	will be returned if the space key was pressed.
DVK_MENU	will be returned if the menu key was pressed.
DVK_ENTER	will be returned if the enter key was pressed.
DVK_CTRL	will be returned if the ctrl key was pressed.
DVK_UP	will be returned if the up key was pressed.
DVK_RIGHT	will be returned if the right key was pressed.
DVK_DOWN	will be returned if the down key was pressed.
DVK_LEFT	will be returned if the left key was pressed.
DVK_ALT	will be returned if the alt key was pressed.

Function Documentation

Keyboard* keyboardDemoInit

(

void

)

initializes the keyboard with default options. Same as calling keyboardInit(NULL, 3, BgType_Text4bpp, BgSize_T_256x512, 20, 0, false, true)

Returns

a pointer to the current keyboard.

int keyboardGetKey	(	int	x,
		int	y
	)

returns the ascii code for the key located at the supplied x and y. Will not effect keyboard shift state.

Parameters

x	the pixel x location
y	the pixel y location

Returns

the key pressed or NOKEY if user pressed outside the keypad

void keyboardGetString	(	char *	buffer,
		int	maxLen
	)

reads the input until a the return key is pressed or the maxLen is exceeded.

Parameters

buffer	a buffer to hold the input string
maxLen	the maximum length to read

Keyboard* keyboardInit	(	Keyboard *	keyboard,
		int	layer,
		BgType	type,
		BgSize	size,
		int	mapBase,
		int	tileBase,
		bool	mainDisplay,
		bool	loadGraphics
	)

initializes the keyboard system with the supplied keyboard

Parameters

keyboard	the keyboard struct to initialize (can be NULL)
layer	the background layer to use
type	the background type to initialize
size	the background size to initialize
mapBase	the map base to use for the background
tileBase	the graphics tile base to use for the background
mainDisplay	if true the keyboard will render on the main display
loadGraphics	if true the keyboard graphics will be loaded

Returns

returns the initialized keyboard struct

int keyboardUpdate

(

void

)

Processes the keyboard. Should be called once per frame when using the keyboard in an async manner.

Returns

the ascii code of the key pressed or -1 if no key was pressed.