DrawableList

touchgfx/containers/scrollers/DrawableList.hpp

A container able to display many items using only a few drawables. This is done by only having drawables for visible items, and populating these drawables with new content when each of these become visible.

This means that all drawables must have an identical structure in some way, for example an Image or a Container with a button and a text.

Inherits from: Container, Drawable

Public Functions

	DrawableList()
virtual bool	getCircular() const
	Gets the circular setting, previously set using setCircular().
int16_t	getDrawableIndex(int16_t itemIndex, int16_t prevDrawableIndex =-1) const
	Gets the drawable index of an item.
int16_t	getDrawableIndices(int16_t itemIndex, int16_t * drawableIndexArray, int16_t arraySize) const
	Gets drawable indices.
virtual int16_t	getDrawableMargin() const
	Gets drawable margin.
virtual int16_t	getDrawableSize() const
	Gets drawable size as set by setDrawables.
virtual bool	getHorizontal() const
	Gets the orientation of the drawables, previously set using setHorizontal().
int16_t	getItemIndex(int16_t drawableIndex) const
	Gets item stored in a given Drawable.
virtual int16_t	getItemSize() const
	Gets size of each item.
int16_t	getNumberOfDrawables() const
	Gets number of drawables based on the size of each item and the size of the widget.
int16_t	getNumberOfItems() const
	Gets number of items in the DrawableList, as previously set using setNumberOfItems().
int32_t	getOffset() const
	Gets offset, as previously set using setOffset().
int16_t	getRequiredNumberOfDrawables() const
	Gets required number of drawables.
void	itemChanged(int16_t itemIndex)
	Item changed.
void	refreshDrawables()
	Refresh drawables.
virtual void	setCircular(bool circular)
	Sets whether the list is circular (infinite) or not.
virtual void	setDrawables(DrawableListItemsInterface & drawableListItems, int16_t drawableItemIndexOffset, GenericCallback< DrawableListItemsInterface *, int16_t, int16_t > & updateDrawableCallback)
	Sets the drawables parameters.
void	setDrawableSize(int16_t drawableSize, int16_t drawableMargin)
	Sets drawables size.
virtual void	setHeight(int16_t height)
	Sets the height of this drawable.
virtual void	setHorizontal(bool horizontal)
	Sets a horizontal or vertical layout.
void	setNumberOfItems(int16_t numberOfItems)
	Sets number of items in the list.
void	setOffset(int32_t ofs)
	Sets virtual coordinate.
virtual void	setWidth(int16_t width)
	Sets the width of this drawable.

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	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	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 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.
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.
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

DrawableList

DrawableList	(			)

getCircular

virtual bool getCircular	(			)	const

Gets the circular setting, previously set using setCircular().

Returns:

True if the list is circular (infinite), false if the list is not circular (finite).

See also:

ScrollBase::getCircular, setCircular

getDrawableIndex

int16_t getDrawableIndex	(	int16_t	itemIndex ,		const
		int16_t	prevDrawableIndex =-1		const
		)	const

Gets the drawable index of an item.

If the number of items is smaller than the number of drawables and the DrawableList is circular, the same item can be in more than one drawable. In that case, calling this function again with the previously returned index as second parameter, the index of the next drawable containing the item will be returned.

Parameters:

itemIndex	Index of the item.
prevDrawableIndex	(Optional) Index of the previous drawable. If given, search starts after this index.

Returns:

The first drawable index with the given item. Returns -1 if the item is not in a drawable.

See also:

getDrawableIndices

getDrawableIndices

int16_t getDrawableIndices	(	int16_t	itemIndex ,		const
		int16_t *	drawableIndexArray ,		const
		int16_t	arraySize		const
		)	const

Gets drawable indices.

Useful when the number of items is smaller than the number of drawables as the same item might be in more than one drawable on the screen (if the DrawableList is circular). The passed array will be filled with the drawable indices and the number of indices found is returned.

Parameters:

itemIndex	Zero-based index of the item.
drawableIndexArray	Array where the drawable indices are stored.
arraySize	Size of drawable array.

Returns:

The number of drawable indices found.

See also:

getItemIndex, setCircular, getDrawableIndex

getDrawableMargin

virtual int16_t getDrawableMargin	(			)	const

Gets drawable margin.

Gets drawable margin as set by setDrawables.

Returns:

The drawable margin.

getDrawableSize

virtual int16_t getDrawableSize	(			)	const

Gets drawable size as set by setDrawables.

Returns:

The drawable size.

See also:

setDrawables

getHorizontal

virtual bool getHorizontal	(			)	const

Gets the orientation of the drawables, previously set using setHorizontal().

Returns:

True if it horizontal, false if it is vertical.

See also:

ScrollBase::getHorizontal, setHorizontal

getItemIndex

int16_t getItemIndex	(	int16_t	drawableIndex	)

Gets item stored in a given Drawable.

Parameters:

drawableIndex	Zero-based index of the drawable.

Returns:

The item index.

getItemSize

virtual int16_t getItemSize	(			)	const

Gets size of each item.

This equals the drawable size plus the drawable margin as set in setDrawables(). Equals getDrawableSize() + 2 * getDrawableMargin().

Returns:

The item size.

Note

Not the same as getDrawableSize().

See also:

setDrawables, setDrawableSize, getDrawableMargin

getNumberOfDrawables

int16_t getNumberOfDrawables	(			)	const

Gets number of drawables based on the size of each item and the size of the widget.

Returns:

The number of drawables.

See also:

setDrawables

getNumberOfItems

int16_t getNumberOfItems	(			)	const

Gets number of items in the DrawableList, as previously set using setNumberOfItems().

Returns:

The number of items.

See also:

setNumberOfItems

getOffset

int32_t getOffset	(			)	const

Gets offset, as previously set using setOffset().

Returns:

The virtual offset.

See also:

setOffset

getRequiredNumberOfDrawables

int16_t getRequiredNumberOfDrawables	(			)	const

Gets required number of drawables.

After setting up the DrawableList it is possible to request how many drawables are needed to ensure that the list can always be drawn properly. If the DrawableList has been setup with fewer Drawables than the required number of drawables, part of the lower part of the DrawableList will look wrong.

The number of required drawables depend on the size of the widget and the size of the drawables and the margin around drawables. If there are fewer drawables than required, the widget will not display correctly. If there are more drawables than required, some will be left unused.

Returns:

The required number of drawables.

See also:

setDrawables

itemChanged

void itemChanged	(	int16_t	itemIndex	)

Item changed.

Item changed and drawables containing this item must be updated. This function can be called when an item has changed and needs to be updated on screen. If the given item is displayed on screen, possible more than once for cyclic lists, each drawable is request to refresh its content to reflect the new value.

Parameters:

itemIndex	Zero-based index of the item.

refreshDrawables

void refreshDrawables	(			)

Refresh drawables.

Useful to call if the number or items, their size or other properties have changed.

setCircular

virtual void setCircular	(	bool	circular	)

Sets whether the list is circular (infinite) or not.

A circular list is a list where the first drawable re-appears after the last item in the list - and the last item in the list appears before the first item in the list.

Parameters:

circular	True if the list should be circular, false if the list should not be circular.

See also:

ScrollBase::setCircular, getCircular

setDrawables

virtual void setDrawables	(	DrawableListItemsInterface &	drawableListItems ,
		int16_t	drawableItemIndexOffset ,
		GenericCallback< DrawableListItemsInterface *, int16_t, int16_t > &	updateDrawableCallback
		)

Sets the drawables parameters.

These parameters are

• The access class to the array of drawables
• The offset in the drawableListItems array to start using drawable and
• Callback to update the contents of a drawable.

Parameters:

drawableListItems	Number of drawables allocated.
drawableItemIndexOffset	The offset of the drawable item.
updateDrawableCallback	A callback to update the contents of a drawable.

See also:

getRequiredNumberOfDrawables

setDrawableSize

void setDrawableSize	(	int16_t	drawableSize ,
		int16_t	drawableMargin
		)

Sets drawables size.

The drawable is is the size of each drawable in the list in the set direction of the list (this is enforced by the DrawableList class). The specified margin is added above and below each item for spacing. The entire size of an item is thus size + 2 * spacing.

For a horizontal list each element will be drawableSize high and have the same width as set using setWidth(). For a vertical list each element will be drawableSize wide and have the same height as set using setHeight().

Parameters:

drawableSize	The size of the drawable.
drawableMargin	The margin around drawables (margin before and margin after).

See also:

setWidth, setHeight, setHorizontal

setHeight

virtual void setHeight	(	int16_t	height	)

Sets the height of this drawable.

Parameters:

height	The new height.

Note

For most Drawable widgets, changing this does normally not automatically yield a redraw.If the list is horizontal, the height is also propagated to all drawables in the list.

Reimplements: touchgfx::Drawable::setHeight

setHorizontal

virtual void setHorizontal	(	bool	horizontal	)

Sets a horizontal or vertical layout.

If parameter horizontal is set true, all drawables are arranged side by side. If horizontal is set false, the drawables are arranged above and below each other (vertically).

Parameters:

horizontal	True to align drawables horizontal, false to align drawables vertically.

Note

Default value is false, i.e. vertical layout.

See also:

ScrollBase::setHorizontal, getHorizontal

setNumberOfItems

void setNumberOfItems	(	int16_t	numberOfItems	)

Sets number of items in the list.

This forces all drawables to be updated to ensure that the content is correct.

Parameters:

numberOfItems	Number of items.

Note

The DrawableList is refreshed to reflect the change.

setOffset

void setOffset	(	int32_t	ofs	)

Sets virtual coordinate.

Does not move to the given coordinate, but places the drawables and fill correct content into the drawables to give the impression that everything has been scrolled to the given coordinate.

Setting a value of 0 means that item 0 is at the start of the DrawableList. Setting a value of "-getItemSize()" places item 0 outside the start of the DrawableList and item 1 at the start of it.

Items that are completely outside of view, will be updated with new content using the provided callback from setDrawables(). Care is taken to not fill drawables more than strictly required.

Parameters:

ofs	The virtual coordinate.

See also:

getOffset, setDrawables

setWidth

virtual void setWidth	(	int16_t	width	)

Sets the width of this drawable.

Parameters:

width	The new width.

Note

For most Drawable widgets, changing this does normally not automatically yield a redraw.If the list is vertical, the width is also propagated to all drawables in the list.

Reimplements: touchgfx::Drawable::setWidth