Keyboard

touchgfx/widgets/Keyboard.hpp

The keyboard provides text input for touch devices. It is configured using a Layout and a KeyMappingList, both of which can be changed at runtime. The class using the keyboard must provide a buffer where the entered text is placed. The Layout contains a bitmap id for the image to display and two mappings: rectangles to key ids and rectangles to callback methods.

The KeyMappingList maps key ids to Unicode characters. When the user presses a key, the keyboard looks in its layout for a rectangle containing the coordinates pressed. If it finds a mapping to a callback method, it will invoke that method. If it finds a mapping to a key it will look up the Unicode character for that key and place it in a text buffer. The sequence is: (x,y) -> KeyId -> UnicodeChar.

A keyboard with multiple key mappings e.g. lower case alpha, upper case alpha and numeric mappings can be created by implementing callback methods for shift and mode areas in the provided bitmap and then changing the KeyMappingList when those areas are pressed.

Inherits from: Container, Drawable

Public Classes

struct	CallbackArea
	Mapping from rectangle to a callback method to execute.
struct	Key
	Mapping from rectangle to key id.
struct	KeyMapping
	Mapping from key id to Unicode character.
struct	KeyMappingList
	List of KeyMappings to use.
struct	Layout
	Definition of the keyboard layout.

Public Functions

virtual void	draw(const Rect & invalidatedArea) const
	Overrides the draw implementation on the Container.
Unicode::UnicodeChar *	getBuffer() const
	Gets the buffer.
uint16_t	getBufferPosition()
	Gets buffer position.
const KeyMappingList *	getKeyMappingList() const
	Gets key mapping list.
const Layout *	getLayout() const
	Gets the layout.
virtual void	handleClickEvent(const ClickEvent & event)
	Overrides the handleClickEvent on the container.
virtual void	handleDragEvent(const DragEvent & event)
	Overrides the handleDragEvent on the container.
	Keyboard()
void	setBuffer(Unicode::UnicodeChar * newBuffer, uint16_t newBufferSize)
	Sets the buffer to be used by the keyboard.
void	setBufferPosition(uint16_t newPos)
	Change the buffer position i.e.
void	setKeyListener(GenericCallback< Unicode::UnicodeChar > & callback)
	Sets the callback for the keyboard.
void	setKeymappingList(const KeyMappingList * newKeyMappingList)
	Set/change the KeyMappingList to use.
void	setLayout(const Layout * newLayout)
	Set/change the Keyboard::Layout to use.The Keyboard will invalidate the space it occupies to request a redraw.
void	setTextIndentation()
	Sets text indentation by making the area for entered text slightly larger.

Protected Functions

CallbackArea	getCallbackAreaForCoordinates(int16_t x, int16_t y) const
	Gets the callback area defined by the layout for the specified coordinates.
Unicode::UnicodeChar	getCharForKey(uint8_t keyId) const
	Maps a keyId to the UnicodeChar being displayed by that key.
Key	getKeyForCoordinates(int16_t x, int16_t y) const
	Gets key for coordinates.

Protected Attributes

Unicode::UnicodeChar *	buffer
	Pointer to null-terminated buffer where the entered text is being displayed.
uint16_t	bufferPosition
	Current position in buffer.
uint16_t	bufferSize
	Size of the buffer.
bool	cancelIsEmitted
	Tells if a cancel is emitted to check when a key is released.
TextAreaWithOneWildcard	enteredText
	Widget capable of displaying the entered text buffer.
Image	highlightImage
	Image to display when a key is highlighted.
Image	image
	Layout bitmap.
GenericCallback< Unicode::UnicodeChar > *	keyListener
	Pointer to callback being executed when a key is pressed.
const KeyMappingList *	keyMappingList
	Pointer to key mapping.
const Layout *	layout
	Pointer to layout.

Additional inherited members

Public Functions inherited from Container

virtual void	add(Drawable & d)
	Adds a Drawable instance as child to this Container.
	Container()
virtual bool	contains(const Drawable & d)
	Query if a given Drawable has been added directly to this Container.
virtual void	forEachChild(GenericCallback< Drawable & > * function)
	Executes the specified callback function for each child in the Container.
virtual Drawable *	getFirstChild()
	Obtain a pointer to the first child of this container.
virtual void	getLastChild(int16_t x, int16_t y, Drawable ** last)
	Gets the last child in the list of children in this Container.
virtual void	getLastChildNear(int16_t x, int16_t y, Drawable * last, int16_t fingerAdjustmentX, int16_t * fingerAdjustmentY)
	Works similar to getLastChild() but also considers the current set finger size in HAL.
virtual Rect	getSolidRect() const
	Get (the largest possible) rectangle that is guaranteed to be solid (opaque).
virtual void	insert(Drawable * previous, Drawable & d)
	Inserts a Drawable after a specific child node.
virtual void	remove(Drawable & d)
	Removes a Drawable from the container by removing it from the linked list of children.
virtual void	removeAll()
	Removes all children in the Container by resetting their parent and sibling pointers.
virtual void	unlink()
	Removes all children by unlinking the first child.

Protected Functions inherited from Container

virtual Rect	getContainedArea() const
	Gets a rectangle describing the total area covered by the children of this container.
virtual void	moveChildrenRelative(int16_t deltaX, int16_t deltaY)
	Calls moveRelative on all children.

Protected Attributes inherited from Container

Drawable *	firstChild
	Pointer to the first child of this container. Subsequent children can be found through firstChild's nextSibling.

Public Functions inherited from Drawable

void	center()
	Centers the Drawable inside its parent.
void	centerX()
	Center the Drawable horizontally inside its parent.
void	centerY()
	Center the Drawable vertically inside its parent.
virtual void	childGeometryChanged()
	This function can be called on parent nodes to signal that the size or position of one or more of its children has changed.
	Drawable()
	Initializes a new instance of the Drawable class.
void	drawToDynamicBitmap(BitmapId id)
	Render the Drawable object into a dynamic bitmap.
void	expand(int margin =0)
	Expands the Drawable to have the same size as its parent with a given margin around the edge.
Rect	getAbsoluteRect() const
	Helper function for obtaining the rectangle this Drawable covers, expressed in absolute coordinates.
virtual Drawable *	getFirstChild()
	Function for obtaining the first child of this drawable if any.
int16_t	getHeight() const
	Gets the height of this Drawable.
virtual void	getLastChild(int16_t x, int16_t y, Drawable ** last) =0
	Function for obtaining the the last child of this drawable that intersects with the specified point.
Drawable *	getNextSibling()
	Gets the next sibling node.
Drawable *	getParent() const
	Returns the parent node.
const Rect &	getRect() const
	Gets the rectangle this Drawable covers, in coordinates relative to its parent.
virtual Rect	getSolidRect() const =0
	Get (the largest possible) rectangle that is guaranteed to be solid (opaque).
virtual Rect	getSolidRectAbsolute()
	Helper function for obtaining the largest solid rect (as implemented by getSolidRect()) expressed in absolute coordinates.
virtual void	getVisibleRect(Rect & rect) const
	Function for finding the visible part of this drawable.
int16_t	getWidth() const
	Gets the width of this Drawable.
int16_t	getX() const
	Gets the x coordinate of this Drawable, relative to its parent.
int16_t	getY() const
	Gets the y coordinate of this Drawable, relative to its parent.
virtual void	handleGestureEvent(const GestureEvent & event)
	Defines the event handler interface for GestureEvents.
virtual void	handleTickEvent()
	Called periodically by the framework if the Drawable instance has subscribed to timer ticks.
virtual void	invalidate() const
	Tell the framework that this entire Drawable needs to be redrawn.
virtual void	invalidateContent() const
	Tell the framework that the contents of the Drawable needs to be redrawn.
virtual void	invalidateRect(Rect & invalidatedArea) const
	Request that a region of this drawable is redrawn.
bool	isTouchable() const
	Gets whether this Drawable receives touch events or not.
bool	isVisible() const
	Gets whether this Drawable is visible.
virtual void	moveRelative(int16_t x, int16_t y)
	Moves the drawable.
virtual void	moveTo(int16_t x, int16_t y)
	Moves the drawable.
virtual void	setHeight(int16_t height)
	Sets the height of this drawable.
void	setPosition(const Drawable & drawable)
	Sets the position of the Drawable to the same as the given Drawable.
void	setPosition(int16_t x, int16_t y, int16_t width, int16_t height)
	Sets the size and position of this Drawable, relative to its parent.
void	setTouchable(bool touch)
	Controls whether this Drawable receives touch events or not.
void	setVisible(bool vis)
	Controls whether this Drawable should be visible.
virtual void	setWidth(int16_t width)
	Sets the width of this drawable.
void	setWidthHeight(const Bitmap & bitmap)
	Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
void	setWidthHeight(const Drawable & drawable)
	Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
void	setWidthHeight(const Rect & other)
	Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
void	setWidthHeight(int16_t width, int16_t height)
	Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
virtual void	setX(int16_t x)
	Sets the x coordinate of this Drawable, relative to its parent.
void	setXY(const Drawable & drawable)
	Sets the x and y coordinates of this Drawable.
void	setXY(int16_t x, int16_t y)
	Sets the x and y coordinates of this Drawable, relative to its parent.
virtual void	setY(int16_t y)
	Sets the y coordinate of this Drawable, relative to its parent.
virtual void	translateRectToAbsolute(Rect & r) const
	Helper function for converting a region of this Drawable to absolute coordinates.
virtual	~Drawable()
	Finalizes an instance of the Drawable class.

Protected Attributes inherited from Drawable

Drawable *	nextSibling
	Pointer to the next Drawable.
Drawable *	parent
	Pointer to this drawable's parent.
Rect	rect
	The coordinates of this Drawable, relative to its parent.
bool	touchable
	True if this drawable should receive touch events.
bool	visible
	True if this drawable should be drawn.

Public Functions Documentation

draw

virtual void draw	(	const Rect &	invalidatedArea	)

Overrides the draw implementation on the Container.

First invokes the container draw implementation to draw the keyboard bitmap and text area holding the entered text. If additional drawables have been added to the keyboard, they will also be draw. After invoking the container draw, the glyphs mapped to keys are drawn and if a key has been pressed, it will be highlighted.

Parameters:

invalidatedArea	The area to draw.

Reimplements: touchgfx::Container::draw

getBuffer

Unicode::UnicodeChar * getBuffer	(			)	const

Gets the buffer.

Returns:

The buffer containing entered text currently being displayed.

See also:

setBuffer

getBufferPosition

uint16_t getBufferPosition	(			)

Gets buffer position.

Returns:

the buffer position, i.e. the current index where new characters will be placed.

See also:

setBufferPosition

getKeyMappingList

const KeyMappingList * getKeyMappingList	(			)	const

Gets key mapping list.

Returns:

The KeyMappingList used by the Keyboard.

getLayout

const Layout * getLayout	(			)	const

Gets the layout.

Returns:

The layout used by the Keyboard.

See also:

setLayout

handleClickEvent

virtual void handleClickEvent	(	const ClickEvent &	event	)

Overrides the handleClickEvent on the container.

The keyboard handles all click events internally and click events are not propagated to drawables added to the keyboard.

Parameters:

event	The ClickEvent.

Reimplements: touchgfx::Drawable::handleClickEvent

handleDragEvent

virtual void handleDragEvent	(	const DragEvent &	event	)

Overrides the handleDragEvent on the container.

The keyboard handles drag events to enable the container to, emit a CANCEL, if the user drags outside the currently pressed key.

Parameters:

event	The DragEvent.

Reimplements: touchgfx::Drawable::handleDragEvent

Keyboard

Keyboard	(			)

setBuffer

void setBuffer	(	Unicode::UnicodeChar *	newBuffer ,
		uint16_t	newBufferSize
		)

Sets the buffer to be used by the keyboard.

Keys entered are added to the buffer.

Parameters:

newBuffer	Pointer to a buffer holding the text edited by the keyboard. If the buffer is not empty, the edit position for the keyboard will be set to the end of the provided text.
newBufferSize	Length of the buffer, i.e. number of UnicodeChar's.

See also:

getBuffer

setBufferPosition

void setBufferPosition	(	uint16_t	newPos	)

Change the buffer position i.e.

the next index to place a character when a key is pressed. This can be used to implement backspace functionality if the class using the Keyboard implements a callback and maps it to a backspace implementation. Setting the position will cause the TextArea displaying the text to be invalidated to request a redraw.

Parameters:

newPos	The buffer position.

See also:

setTextIndentation

setKeyListener

void setKeyListener	(	GenericCallback< Unicode::UnicodeChar > &	callback	)

Sets the callback for the keyboard.

The callback will be executed every time a key is clicked. The callback argument contains the key that was just pressed.

Parameters:

callback	The Callback to invoke.

Note

Backspace, shift and mode keys report a 0 as value.

setKeymappingList

void setKeymappingList	(	const KeyMappingList *	newKeyMappingList	)

Set/change the KeyMappingList to use.

The Keyboard will invalidate the space it occupies to request a redraw.

Parameters:

newKeyMappingList	The new KeyMappingList.

setLayout

void setLayout	(	const Layout *	newLayout	)

Set/change the Keyboard::Layout to use.The Keyboard will invalidate the space it occupies to request a redraw.

Parameters:

newLayout	The new layout.

See also:

getLayout

setTextIndentation

void setTextIndentation	(			)

Sets text indentation by making the area for entered text slightly larger.

The result is that some characters (often 'j' and '_') will not be cut off. Indentation is added to both sides of the text area in case the text is right-to-left. Indentation is automatically set so all characters will display properly.

See also:

TextArea::setIndentation

Protected Functions Documentation

getCallbackAreaForCoordinates

CallbackArea getCallbackAreaForCoordinates	(	int16_t	x ,		const
		int16_t	y		const
		)	const

Gets the callback area defined by the layout for the specified coordinates.

Parameters:

x	The x coordinate to perform key look up with.
y	The y coordinate to perform key look up with.

Returns:

The CallbackArea, which is empty if not found.

getCharForKey

Unicode::UnicodeChar getCharForKey	(	uint8_t	keyId	)

Maps a keyId to the UnicodeChar being displayed by that key.

Parameters:

keyId	The id of the key to perform lookup with.

Returns:

the UnicodeChar used for the specified key.

getKeyForCoordinates

Key getKeyForCoordinates	(	int16_t	x ,		const
		int16_t	y		const
		)	const

Gets key for coordinates.

Parameters:

x	The x coordinate to perform key look up with.
y	The y coordinate to perform key look up with.

Returns:

The key for the given coordinates.

Protected Attributes Documentation

buffer

Unicode::UnicodeChar * buffer

Pointer to null-terminated buffer where the entered text is being displayed.

bufferPosition

uint16_t bufferPosition

Current position in buffer.

bufferSize

uint16_t bufferSize

Size of the buffer.

cancelIsEmitted

bool cancelIsEmitted

Tells if a cancel is emitted to check when a key is released.

enteredText

TextAreaWithOneWildcard enteredText

Widget capable of displaying the entered text buffer.

highlightImage

Image highlightImage

Image to display when a key is highlighted.

image

Image image

Layout bitmap.

keyListener

GenericCallback< Unicode::UnicodeChar > * keyListener

Pointer to callback being executed when a key is pressed.

keyMappingList

const KeyMappingList * keyMappingList

Pointer to key mapping.

layout

const Layout * layout

Pointer to layout.