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Version: 4.16

ScrollWheelBase

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#

intgetSelectedItem() const
Gets selected item.
virtual int16_tgetSelectedItemOffset() const
Gets offset of selected item measured in pixels relative to the start of the widget.
virtual voidhandleClickEvent(const ClickEvent & evt)
Defines the event handler interface for ClickEvents.
virtual voidhandleDragEvent(const DragEvent & evt)
Defines the event handler interface for DragEvents.
virtual voidhandleGestureEvent(const GestureEvent & evt)
Defines the event handler interface for GestureEvents.
virtual int32_tkeepOffsetInsideLimits(int32_t newOffset, int16_t overShoot) const
Keep offset inside limits.
ScrollWheelBase()
voidsetAnimateToCallback(GenericCallback< int16_t > & callback)
Sets Callback which will be called when the ScrollWheel animates to a new item.
virtual voidsetSelectedItemOffset(int16_t offset)
Sets selected item offset, measured in pixels, from the edge of the widget.

Protected Functions#

virtual voidanimateToPosition(int32_t position, int16_t steps =-1)
Animate to a new position/offset using the given number of steps.
virtual int32_tgetPositionForItem(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#

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

Public Functions inherited from ScrollBase#

voidallowHorizontalDrag(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).
voidallowVerticalDrag(bool enable)
Enables the vertical scroll.
virtual voidanimateToItem(int16_t itemIndex, int16_t animationSteps =-1)
Go to a specific item, possibly with animation.
uint16_tgetAnimationSteps() const
Gets animation steps as set in setAnimationSteps.
virtual boolgetCircular() const
Gets the circular setting, previously set using setCircular().
uint16_tgetDragAcceleration() const
Gets drag acceleration (times 10).
virtual int16_tgetDrawableMargin() const
Gets drawable margin as set through the second parameter in most recent call to setDrawableSize().
virtual int16_tgetDrawableSize() const
Gets drawable size as set through the first parameter in most recent call to setDrawableSize().
virtual boolgetHorizontal() const
Gets the orientation of the drawables, previously set using setHorizontal().
uint16_tgetMaxSwipeItems() const
Gets maximum swipe items as set by setMaxSwipeItems.
virtual int16_tgetNumberOfItems() const
Gets number of items in the DrawableList, as previously set using setNumberOfItems().
uint16_tgetSwipeAcceleration() const
Gets swipe acceleration (times 10).
virtual voidhandleTickEvent()
Called periodically by the framework if the Drawable instance has subscribed to timer ticks.
virtual voidinitialize()
Removed all drawables and initializes the content of these items.
boolisAnimating() const
Query if an animation is ongoing.
virtual voiditemChanged(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()
voidsetAnimationEndedCallback(GenericCallback<> & callback)
Callback, called when the set animation ended.
voidsetAnimationSteps(int16_t steps)
Sets animation steps (in ticks) when moving to a new selected item.
virtual voidsetCircular(bool circular)
Sets whether the list is circular (infinite) or not.
voidsetDragAcceleration(uint16_t acceleration)
Sets drag acceleration times 10, so "10" means "1", "15" means "1.5".
voidsetDrawableSize(int16_t drawableSize, int16_t drawableMargin)
Sets drawables size.
voidsetEasingEquation(EasingEquation equation)
Sets easing equation when changing the selected item, for example via swipe or AnimateTo.
virtual voidsetHeight(int16_t height)
Sets the height of this drawable.
virtual voidsetHorizontal(bool horizontal)
Sets a horizontal or vertical layout.
voidsetItemPressedCallback(GenericCallback< int16_t > & callback)
Set Callback which will be called when a item is pressed.
voidsetItemSelectedCallback(GenericCallback< int16_t > & callback)
Sets Callback which will be called when the selected item is clicked.
voidsetMaxSwipeItems(uint16_t maxItems)
Sets maximum swipe items.
virtual voidsetNumberOfItems(int16_t numberOfItems)
Sets number of items in the DrawableList.
voidsetSwipeAcceleration(uint16_t acceleration)
Sets swipe acceleration (times 10).
virtual voidsetWidth(int16_t width)
Sets the width of this drawable.
voidstopAnimation()
Stops an animation if one is ongoing.

Protected Functions inherited from ScrollBase#

virtual int32_tgetNearestAlignedOffset(int32_t offset) const
Gets nearest offset aligned to a multiple of itemSize.
intgetNormalizedOffset(int offset) const
Gets normalized offset from a given offset from 0 down to -numItems*itemSize.
virtual int32_tgetOffset() const
Gets display offset of first item.
virtual voidsetOffset(int32_t offset)
Sets display offset of first item.

Protected Attributes inherited from ScrollBase#

GenericCallback *animationEndedCallback
The animation ended callback.
AnimationStatecurrentAnimationState
The current animation state.
uint16_tdefaultAnimationSteps
The animation steps.
int16_tdistanceBeforeAlignedItem
The distance before aligned item.
uint16_tdragAcceleration
The drag acceleration x10.
booldraggableX
Is the container draggable in the horizontal direction.
booldraggableY
Is the container draggable in the vertical direction.
EasingEquationeasingEquation
The easing equation used for animation.
intgestureEnd
The gesture end.
intgestureStart
The gesture start.
intgestureStep
The current gesture step.
intgestureStepsTotal
The total gesture steps.
int32_tinitialSwipeOffset
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_titemSize
Size of the item (including margin)
DrawableListlist
The list.
uint16_tmaxSwipeItems
The maximum swipe items.
int16_tnumberOfDrawables
Number of drawables.
uint16_tswipeAcceleration
The swipe acceleration x10.
int16_txClick
The x coordinate of a click.
int16_tyClick
The y coordinate of a click.

Public Functions inherited from Container#

virtual voidadd(Drawable & d)
Adds a Drawable instance as child to this Container.
Container()
virtual boolcontains(const Drawable & d)
Query if a given Drawable has been added directly to this Container.
virtual voiddraw(const Rect & invalidatedArea) const
Draw this drawable.
virtual voidforEachChild(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 voidgetLastChild(int16_t x, int16_t y, Drawable ** last)
Gets the last child in the list of children in this Container.
virtual RectgetSolidRect() const
Get (the largest possible) rectangle that is guaranteed to be solid (opaque).
virtual voidinsert(Drawable * previous, Drawable & d)
Inserts a Drawable after a specific child node.
virtual voidremove(Drawable & d)
Removes a Drawable from the container by removing it from the linked list of children.
virtual voidremoveAll()
Removes all children in the Container by resetting their parent and sibling pointers.
virtual voidunlink()
Removes all children by unlinking the first child.

Protected Functions inherited from Container#

virtual RectgetContainedArea() const
Gets a rectangle describing the total area covered by the children of this container.
virtual voidmoveChildrenRelative(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#

virtual voidchildGeometryChanged()
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 voiddraw(const Rect & invalidatedArea) const =0
Draw this drawable.
Drawable()
Initializes a new instance of the Drawable class.
voiddrawToDynamicBitmap(BitmapId id)
Render the Drawable object into a dynamic bitmap.
RectgetAbsoluteRect() 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_tgetHeight() const
Gets the height of this Drawable.
virtual voidgetLastChild(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 RectgetSolidRect() const =0
Get (the largest possible) rectangle that is guaranteed to be solid (opaque).
virtual RectgetSolidRectAbsolute()
Helper function for obtaining the largest solid rect (as implemented by getSolidRect()) expressed in absolute coordinates.
virtual voidgetVisibleRect(Rect & rect) const
Function for finding the visible part of this drawable.
int16_tgetWidth() const
Gets the width of this Drawable.
int16_tgetX() const
Gets the x coordinate of this Drawable, relative to its parent.
int16_tgetY() const
Gets the y coordinate of this Drawable, relative to its parent.
virtual voidhandleTickEvent()
Called periodically by the framework if the Drawable instance has subscribed to timer ticks.
virtual voidinvalidate() const
Tell the framework that this entire Drawable needs to be redrawn.
virtual voidinvalidateRect(Rect & invalidatedArea) const
Request that a region of this drawable is redrawn.
boolisTouchable() const
Gets whether this Drawable receives touch events or not.
boolisVisible() const
Gets whether this Drawable is visible.
virtual voidmoveRelative(int16_t x, int16_t y)
Moves the drawable.
virtual voidmoveTo(int16_t x, int16_t y)
Moves the drawable.
virtual voidsetHeight(int16_t height)
Sets the height of this drawable.
voidsetPosition(const Drawable & drawable)
Sets the position of the Drawable to the same as the given Drawable.
voidsetPosition(int16_t x, int16_t y, int16_t width, int16_t height)
Sets the size and position of this Drawable, relative to its parent.
voidsetTouchable(bool touch)
Controls whether this Drawable receives touch events or not.
voidsetVisible(bool vis)
Controls whether this Drawable should be visible.
virtual voidsetWidth(int16_t width)
Sets the width of this drawable.
voidsetWidthHeight(const Bitmap & bitmap)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
voidsetWidthHeight(const Drawable & drawable)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
voidsetWidthHeight(const Rect & rect)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
voidsetWidthHeight(int16_t width, int16_t height)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
virtual voidsetX(int16_t x)
Sets the x coordinate of this Drawable, relative to its parent.
voidsetXY(const Drawable & drawable)
Sets the x and y coordinates of this Drawable.
voidsetXY(int16_t x, int16_t y)
Sets the x and y coordinates of this Drawable, relative to its parent.
virtual voidsetY(int16_t y)
Sets the y coordinate of this Drawable, relative to its parent.
virtual voidtranslateRectToAbsolute(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.
Rectrect
The coordinates of this Drawable, relative to its parent.
booltouchable
True if this drawable should receive touch events.
boolvisible
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:

handleClickEvent#

virtual void handleClickEvent(const ClickEvent &evt)

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:
evtThe ClickEvent received from the HAL.

Reimplements: touchgfx::Drawable::handleClickEvent

handleDragEvent#

virtual void handleDragEvent(const DragEvent &evt)

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:
evtThe DragEvent received from the HAL.

Reimplements: touchgfx::ScrollBase::handleDragEvent

handleGestureEvent#

virtual void handleGestureEvent(const GestureEvent &evt)

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:
evtThe GestureEvent received from the HAL.

Reimplements: touchgfx::ScrollBase::handleGestureEvent

keepOffsetInsideLimits#

virtual int32_t keepOffsetInsideLimits(int32_tnewOffset ,const
int16_toverShootconst
)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:
newOffsetThe new offset.
overShootThe over shoot.
Returns:

The new offset inside the limits.

Reimplements: touchgfx::ScrollBase::keepOffsetInsideLimits

ScrollWheelBase#

setAnimateToCallback#

void setAnimateToCallback(GenericCallback< int16_t > &callback)

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

Parameters:
callbackThe callback.

setSelectedItemOffset#

virtual void setSelectedItemOffset(int16_toffset)

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:
offsetThe offset.
See also:

Reimplemented by: touchgfx::ScrollWheelWithSelectionStyle::setSelectedItemOffset

Protected Functions Documentation#

animateToPosition#

virtual void animateToPosition(int32_tposition ,
int16_tsteps =-1
)

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

Parameters:
positionThe new position.
steps(Optional) The steps.

Reimplements: touchgfx::ScrollBase::animateToPosition

getPositionForItem#

virtual int32_t getPositionForItem(int16_titemIndex)

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:
itemIndexZero-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.