ScrollWheelBase

touchgfx/containers/scrollers/ScrollWheelBase.hpp

A base class for a scroll wheel. A scroll wheel is very much like the digit selector on a padlock with numbers. The digits always snap into place and exactly one number is always the "selected" number. Using ScrollWheel, all elements look the same, but an underlying bitmap can help emphasize the "selected" element. The ScrollWheelWithSelectionStyle can have a completely different style on the "selected" item - the font can be larger or bold and images can change color - this can help to give a kind of 3D effect using very few resources.

See: ScrollWheel, ScrollWheelWithSelectionStyle

Inherits from: ScrollBase, Container, Drawable

Inherited by: ScrollWheel, ScrollWheelWithSelectionStyle

Public Functions

int	getSelectedItem() const
	Gets selected item.
virtual int16_t	getSelectedItemOffset() const
	Gets offset of selected item measured in pixels relative to the start of the widget.
virtual void	handleClickEvent(const ClickEvent & event)
	Defines the event handler interface for ClickEvents.
virtual void	handleDragEvent(const DragEvent & event)
	Defines the event handler interface for DragEvents.
virtual void	handleGestureEvent(const GestureEvent & event)
	Defines the event handler interface for GestureEvents.
virtual int32_t	keepOffsetInsideLimits(int32_t newOffset, int16_t overShoot) const
	Keep offset inside limits.
	ScrollWheelBase()
void	setAnimateToCallback(GenericCallback< int16_t > & callback)
	Sets Callback which will be called when the ScrollWheel animates to a new item.
virtual void	setSelectedItemOffset(int16_t offset)
	Sets selected item offset, measured in pixels, from the edge of the widget.

Protected Functions

virtual void	animateToPosition(int32_t position, int16_t steps =-1)
	Animate to a new position/offset using the given number of steps.
virtual int32_t	getPositionForItem(int16_t itemIndex)
	Get the position for an item.

Protected Attributes

GenericCallback< int16_t > *	animateToCallback
	The animate to callback.

Additional inherited members

Protected Types inherited from ScrollBase

enum	AnimationState { NO_ANIMATION, ANIMATING_GESTURE, ANIMATING_DRAG }
	Values that represent animation states.

Public Functions inherited from ScrollBase

void	allowHorizontalDrag(bool enable)
	Enables horizontal scrolling to be passed to the children in the list (in case a child widget is able to handle drag events).
void	allowVerticalDrag(bool enable)
	Enables the vertical scroll.
virtual void	animateToItem(int16_t itemIndex, int16_t animationSteps =-1)
	Go to a specific item, possibly with animation.
uint16_t	getAnimationSteps() const
	Gets animation steps as set in setAnimationSteps.
virtual bool	getCircular() const
	Gets the circular setting, previously set using setCircular().
uint16_t	getDragAcceleration() const
	Gets drag acceleration (times 10).
virtual int16_t	getDrawableMargin() const
	Gets drawable margin as set through the second parameter in most recent call to setDrawableSize().
virtual int16_t	getDrawableSize() const
	Gets drawable size as set through the first parameter in most recent call to setDrawableSize().
virtual bool	getHorizontal() const
	Gets the orientation of the drawables, previously set using setHorizontal().
uint16_t	getMaxSwipeItems() const
	Gets maximum swipe items as set by setMaxSwipeItems.
virtual int16_t	getNumberOfItems() const
	Gets number of items in the DrawableList, as previously set using setNumberOfItems().
uint8_t	getOvershootPercentage() const
	Gets overshoot percentage, as previously set using setOvershootPercentage.
uint16_t	getSwipeAcceleration() const
	Gets swipe acceleration (times 10).
virtual void	handleTickEvent()
	Called periodically by the framework if the Drawable instance has subscribed to timer ticks.
virtual void	initialize()
	Removed all drawables and initializes the content of these items.
bool	isAnimating() const
	Query if an animation is ongoing.
virtual void	itemChanged(int itemIndex)
	Inform the scroll list that the contents of an item has changed and force all drawables with the given item index to be updated via the callback provided.
	ScrollBase()
void	setAnimationEndedCallback(GenericCallback<> & callback)
	Callback, called when the set animation ended.
void	setAnimationSteps(int16_t steps)
	Sets animation steps (in ticks) when moving to a new selected item.
virtual void	setCircular(bool circular)
	Sets whether the list is circular (infinite) or not.
void	setDragAcceleration(uint16_t acceleration)
	Sets drag acceleration times 10, so "10" means "1", "15" means "1.5".
virtual void	setDrawableSize(int16_t drawableSize, int16_t drawableMargin)
	Sets drawables size.
void	setEasingEquation(EasingEquation equation)
	Sets easing equation when changing the selected item, for example via swipe or AnimateTo.
virtual void	setHeight(int16_t height)
	Sets the height of this drawable.
virtual void	setHorizontal(bool horizontal)
	Sets a horizontal or vertical layout.
void	setItemPressedCallback(GenericCallback< int16_t > & callback)
	Set Callback which will be called when a item is pressed.
void	setItemSelectedCallback(GenericCallback< int16_t > & callback)
	Sets Callback which will be called when the selected item is clicked.
void	setMaxSwipeItems(uint16_t maxItems)
	Sets maximum swipe items.
virtual void	setNumberOfItems(int16_t numberOfItems)
	Sets number of items in the DrawableList.
void	setOvershootPercentage(uint8_t percentage)
	Sets overshoot percentage when dragging a non-circular list.
void	setSwipeAcceleration(uint16_t acceleration)
	Sets swipe acceleration (times 10).
virtual void	setWidth(int16_t width)
	Sets the width of this drawable.
void	stopAnimation()
	Stops an animation if one is ongoing.

Protected Functions inherited from ScrollBase

virtual int32_t	getNearestAlignedOffset(int32_t offset) const
	Gets nearest offset aligned to a multiple of itemSize.
int	getNormalizedOffset(int offset) const
	Gets normalized offset from a given offset from 0 down to -numItems*itemSize.
virtual int32_t	getOffset() const
	Gets display offset of first item.
virtual void	setOffset(int32_t offset)
	Sets display offset of first item.

Protected Attributes inherited from ScrollBase

GenericCallback *	animationEndedCallback
	The animation ended callback.
AnimationState	currentAnimationState
	The current animation state.
uint16_t	defaultAnimationSteps
	The animation steps.
int16_t	distanceBeforeAlignedItem
	The distance before aligned item.
uint16_t	dragAcceleration
	The drag acceleration x10.
bool	draggableX
	Is the container draggable in the horizontal direction.
bool	draggableY
	Is the container draggable in the vertical direction.
EasingEquation	easingEquation
	The easing equation used for animation.
int	gestureEnd
	The gesture end.
int	gestureStart
	The gesture start.
int	gestureStep
	The current gesture step.
int	gestureStepsTotal
	The total gesture steps.
int32_t	initialSwipeOffset
	The initial swipe offset.
GenericCallback *	itemLockedInCallback
	The item locked in callback.
GenericCallback< int16_t > *	itemPressedCallback
	The item pressed callback.
GenericCallback< int16_t > *	itemSelectedCallback
	The item selected callback.
int16_t	itemSize
	Size of the item (including margin)
DrawableList	list
	The list.
uint16_t	maxSwipeItems
	The maximum swipe items.
int16_t	numberOfDrawables
	Number of drawables.
uint8_t	overshootPercentage
	The overshoot percentage when dragging.
uint16_t	swipeAcceleration
	The swipe acceleration x10.
int16_t	xClick
	The x coordinate of a click.
int16_t	yClick
	The y coordinate of a click.

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	draw(const Rect & invalidatedArea) const
	Draw this drawable.
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.
virtual void	draw(const Rect & invalidatedArea) const =0
	Draw this drawable.
	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	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

getSelectedItem

int getSelectedItem	(			)	const

Gets selected item.

If an animation is in progress, the item that is being scrolled to is returned, not the item that happens to be flying by at the time.

Returns:

The selected item.

getSelectedItemOffset

virtual int16_t getSelectedItemOffset	(			)	const

Gets offset of selected item measured in pixels relative to the start of the widget.

Returns:

The selected item offset.

See also:

setSelectedItemOffset

handleClickEvent

virtual void handleClickEvent	(	const ClickEvent &	event	)

Defines the event handler interface for ClickEvents.

The default implementation ignores the event. The event is only received if the Drawable is touchable and visible.

Parameters:

event	The ClickEvent received from the HAL.

Reimplements: touchgfx::Drawable::handleClickEvent

handleDragEvent

virtual void handleDragEvent	(	const DragEvent &	event	)

Defines the event handler interface for DragEvents.

The default implementation ignores the event. The event is only received if the drawable is touchable and visible.

Parameters:

event	The DragEvent received from the HAL.

Reimplements: touchgfx::ScrollBase::handleDragEvent

handleGestureEvent

virtual void handleGestureEvent	(	const GestureEvent &	event	)

Defines the event handler interface for GestureEvents.

The default implementation ignores the event. The event is only received if the Drawable is touchable and visible.

Parameters:

event	The GestureEvent received from the HAL.

Reimplements: touchgfx::ScrollBase::handleGestureEvent

keepOffsetInsideLimits

virtual int32_t keepOffsetInsideLimits	(	int32_t	newOffset ,		const
		int16_t	overShoot		const
		)	const

Keep offset inside limits.

Return the new offset that is inside the limits of the scroll list, with the overShoot value added at both ends of the list.

Parameters:

newOffset	The new offset.
overShoot	The over shoot.

Returns:

The new offset inside the limits.

Reimplements: touchgfx::ScrollBase::keepOffsetInsideLimits

ScrollWheelBase

ScrollWheelBase	(			)

setAnimateToCallback

void setAnimateToCallback	(	GenericCallback< int16_t > &	callback	)

Sets Callback which will be called when the ScrollWheel animates to a new item.

Parameters:

callback	The callback.

setSelectedItemOffset

virtual void setSelectedItemOffset	(	int16_t	offset	)

Sets selected item offset, measured in pixels, from the edge of the widget.

The offset is the relative x coordinate if the ScrollWheel is horizontal, otherwise it is the relative y coordinate. If this value is zero, the selected item is placed at the very start of the widget.

Parameters:

offset	The offset.

See also:

getSelectedItemOffset

Reimplemented by: touchgfx::ScrollWheelWithSelectionStyle::setSelectedItemOffset

Protected Functions Documentation

animateToPosition

virtual void animateToPosition	(	int32_t	position ,
		int16_t	steps =-1
		)

Animate to a new position/offset using the given number of steps.

Parameters:

position	The new position.
steps	(Optional) The steps.

Reimplements: touchgfx::ScrollBase::animateToPosition

getPositionForItem

virtual int32_t getPositionForItem	(	int16_t	itemIndex	)

Get the position for an item.

The position should ensure that the item is in view as defined by the semantics of the actual scroll class. If the item is already in view, the current offset is returned and not the offset of the given item.

Parameters:

itemIndex	Zero-based index of the item.

Returns:

The position for item.

Reimplements: touchgfx::ScrollBase::getPositionForItem

Protected Attributes Documentation

animateToCallback

GenericCallback< int16_t > * animateToCallback

The animate to callback.