The BCardLayout class is a simple BLayout subclass that arranges the items as a stack of cards with only one card being on top and visible to the user. More...

Inherits BAbstractLayout.

Public Member Functions
	BCardLayout ()
	Create a new card layout.

	BCardLayout (BMessage *from)
	Constructs a BCardLayout from an archive message.

virtual	~BCardLayout ()
	Destructor.

virtual status_t	Archive (BMessage *into, bool deep=true) const
	Archive this layout into a BMessage.

virtual BAlignment	BaseAlignment ()
	Overridden hook method from BAbstractLayout.

virtual BSize	BaseMaxSize ()
	Overridden hook method from BAbstractLayout.

virtual BSize	BaseMinSize ()
	Overridden hook method from BAbstractLayout.

virtual BSize	BasePreferredSize ()
	Overridden hook method from BAbstractLayout.

virtual void	GetHeightForWidth (float width, float min, float max, float *preferred)
	Overridden hook method from BAbstractLayout.

virtual bool	HasHeightForWidth ()
	Overridden hook method from BAbstractLayout.

virtual status_t	Perform (perform_code d, void *arg)
	Overridden hook method from BAbstractLayout.

void	SetVisibleItem (BLayoutItem *item)
	Set the current visible item to item.

void	SetVisibleItem (int32 index)
	Set the current visible item to the item at index.

int32	VisibleIndex () const
	Get the index of the currently visible item.

BLayoutItem *	VisibleItem () const
	Get a pointer to the currently visible item.

Public Member Functions inherited from BAbstractLayout
virtual BAlignment	Alignment ()

virtual status_t	Archive (BMessage *into, bool deep=true) const
	Archives this layout into archive. If deep is true, also archives the items in this layout, calling ItemArchived() for each one.

virtual BRect	Frame ()
	Return the bounding frame of this item.

virtual bool	IsVisible ()
	Return the current local visibility of this item. If an item is not visible, it will not be given space by the BLayout it resides in.

virtual BSize	MaxSize ()

virtual BSize	MinSize ()

virtual status_t	Perform (perform_code d, void *arg)
	Perform some action (Internal method defined for binary compatibility purposes).

virtual BSize	PreferredSize ()

virtual void	SetExplicitAlignment (BAlignment alignment)
	Set this item's explicit alignment, to be used in Alignment().

virtual void	SetExplicitMaxSize (BSize size)
	Set this item's explicit max size, to be used in MaxSize().

virtual void	SetExplicitMinSize (BSize size)
	Set this item's explicit min size, to be used in MinSize().

virtual void	SetExplicitPreferredSize (BSize size)
	Set this item's explicit preferred size, to be used in PreferredSize().

virtual void	SetFrame (BRect frame)
	Set the bounding frame of this item.

virtual void	SetVisible (bool visible)
	Set the local visibility of this item.

	BAbstractLayout ()
	Construct a BAbstractLayout.

	BAbstractLayout (BMessage *from)
	Archive constructor.

Public Member Functions inherited from BLayout
	BLayout ()
	Default constructor.

	BLayout (BMessage *archive)
	Archive constructor.

virtual	~BLayout ()
	Destructor, deletes all BLayoutItem's that this layout manages, and detaches from this BLayout's owner view if there is one.

virtual status_t	Perform (perform_code d, void *arg)
	Perform some action (Internal method defined for binary compatibility purposes).

BView *	Owner () const
	Returns the Owner of this layout, i.e. the view this layout manages.

BView *	TargetView () const
	Returns the target view of this layout.

virtual BView *	View ()
	Returns the same BView* as BLayout::Owner(), this method is inherited from BLayoutItem.

virtual BLayoutItem *	AddView (BView *child)
	Creates a BLayoutItem to represent a BView, and adds that item to this layout.

virtual BLayoutItem *	AddView (int32 index, BView *child)
	Creates a BLayoutItem to represent child, and adds that item at index to this layout. child is added to this BLayout's target view.

virtual bool	AddItem (BLayoutItem *item)
	Adds a BLayoutItem to this layout, and adds the BView it represents to this BLayout's target view.

virtual bool	AddItem (int32 index, BLayoutItem *item)
	Adds item to this layout, and adds the BView item represents to this BLayout's target view.

virtual bool	RemoveView (BView *child)
	Removes and deletes all BLayoutItem representing a BView from this layout.

virtual bool	RemoveItem (BLayoutItem *item)
	Removes a BLayoutItem from this layout, and also removes the view it represents from this BLayout's target view.

virtual BLayoutItem *	RemoveItem (int32 index)
	Remove the BLayoutItem at index.

BLayoutItem *	ItemAt (int32 index) const
	Get the BLayoutItem at index. Returns `NULL` if index is out of bounds.

int32	CountItems () const
	Get the number of BLayoutItem s in this layout.

int32	IndexOfItem (const BLayoutItem *item) const
	Get the index of a BLayoutItem in this layout.

int32	IndexOfView (BView *child) const
	Get the index of child in this layout.

virtual void	Relayout (bool immediate=false)
	Request this BLayout to reposition and resize its items as required.

void	LayoutItems (bool force=false)
	If there is no layout currently ongoing, and force is `false`, creates a new BLayoutContext and calls the DoLayout() method of this BLayout and any BLayout's nested in this BLayout.

BLayoutContext *	LayoutContext () const
	Returns the BLayoutContext this BLayout is currently operating in, or `NULL`.

bool	AncestorsVisible () const
	Get the visibility of the ancestors of this layout.

BRect	LayoutArea ()
	Returns the on-screen area this layout has received to lay out its items in.

virtual void	InvalidateLayout (bool children=false)
	Invalidate this layout and any cached data this layout has relating to positioning and sizing of its items.

void	RequireLayout ()
	Flag this layout as stale, i.e. any cached data may still be valid, but the items need to be repositioned or resized.

bool	IsValid ()
	Returns whether this layout has been invalidated (via BLayout::InvalidateLayout()) and has not yet been validated (by doing a layout, or by its ResetLayoutInvalidation() method.

void	EnableLayoutInvalidation ()
	Re-enable layout invalidation after a call to DisableLayoutInvalidation().

void	DisableLayoutInvalidation ()
	Disable layout invalidation notifications, i.e. calls to this object's InvalidateLayout() method.

Public Member Functions inherited from BLayoutItem
	BLayoutItem (BMessage *from)
	Archive constructor.

virtual status_t	Archive (BMessage *into, bool deep=true) const
	Archive the object into a BMessage.

BLayout *	Layout () const
	Returns the BLayout this BLayoutItem resides in.

virtual status_t	Perform (perform_code d, void *arg)
	Perform some action (Internal method defined for binary compatibility purposes).

bool	RemoveSelf ()
	Remove this layout item from the BLayout it is a part of.

virtual BView *	View ()
	Return the BView this item is representing, or `NULL` if it does not represent any view.

void	SetExplicitSize (BSize size)
	Set the explicity size to size.

void	AlignInFrame (BRect frame)
	Position this BLayoutItem within frame, given the value returned by Alignment(), and the size constraints for this item.

void *	LayoutData () const
	Retrieve arbitrary data attached to this BLayoutItem.

void	SetLayoutData (void *data)
	Attach arbitrary data to this BLayoutItem.

Public Member Functions inherited from BArchivable
	BArchivable ()
	Constructor. Does nothing.

	BArchivable (BMessage *from)
	Constructor. Does important behind-the-scenes work in the unarchiving process.

virtual	~BArchivable ()
	Destructor. Does nothing.

virtual status_t	AllArchived (BMessage *archive) const
	Method relating to the use of `BArchiver`.

virtual status_t	AllUnarchived (const BMessage *archive)
	Method relating to the use of `BUnarchiver`.

virtual status_t	Archive (BMessage *into, bool deep=true) const
	Archive the object into a BMessage.

virtual status_t	Perform (perform_code d, void *arg)
	Perform some action (Internal method defined for binary compatibility purposes).

Static Public Member Functions
static BArchivable *	Instantiate (BMessage *from)
	Instantiate a BCardLayout object from message from.

Static Public Member Functions inherited from BArchivable
static BArchivable *	Instantiate (BMessage *archive)
	Static member to restore objects from messages.

Protected Member Functions
virtual status_t	AllArchived (BMessage *archive) const
	Hook method overridden from BArchivable.

virtual status_t	AllUnarchived (const BMessage *from)
	Hook method overridden from BArchivable.

virtual void	DoLayout ()
	Hook method overridden from BAbstractLayout.

virtual bool	ItemAdded (BLayoutItem *item, int32 atIndex)
	Hook method overridden from BAbstractLayout.

virtual status_t	ItemArchived (BMessage into, BLayoutItem item, int32 index) const
	Hook method overridden from BArchivable.

virtual void	ItemRemoved (BLayoutItem *item, int32 fromIndex)
	Hook method overridden from BAbstractLayout.

virtual status_t	ItemUnarchived (const BMessage from, BLayoutItem item, int32 index)
	Hook method overridden from BArchivable.

virtual void	LayoutInvalidated (bool children=false)
	Hook method overridden from BAbstractLayout.

Protected Member Functions inherited from BAbstractLayout
virtual status_t	AllArchived (BMessage *archive) const
	Method relating to the use of `BArchiver`.

virtual status_t	AllUnarchived (const BMessage *from)
	Unarchives the BLayoutItem's for this layout, calling ItemUnarchived() for each one.

virtual void	AncestorVisibilityChanged (bool shown)
	Hook method inherited from BLayoutItem, classes derived from BLayout must include the BLayout version of this method in their implementation.

virtual void	AttachedToLayout ()
	Hook method inherited from BLayoutItem, classes derived from BLayout must include the BLayout version of this method in their implementation.

virtual void	DetachedFromLayout (BLayout *layout)
	Hook method inherited from BLayoutItem, classes derived from BLayout must include the BLayout version of this method in their implementation.

virtual bool	ItemAdded (BLayoutItem *item, int32 atIndex)
	Hook method called when item is added to this layout.

virtual status_t	ItemArchived (BMessage into, BLayoutItem item, int32 index) const
	Hook for derived classes to add data specific to item to the into BMessage. item resides at index.

virtual void	ItemRemoved (BLayoutItem *item, int32 fromIndex)
	Hook method called when item is removed from this layout.

virtual status_t	ItemUnarchived (const BMessage from, BLayoutItem item, int32 index)
	Hook for derived classes to retrieve data specific to item from the from BMessage. item resides at index.

virtual void	LayoutInvalidated (bool children)

virtual void	OwnerChanged (BView *was)
	Hook method called when this layout is attached to a BView.

Protected Member Functions inherited from BLayout
virtual status_t	AllArchived (BMessage *archive) const
	Method relating to the use of `BArchiver`.

void	VisibilityChanged (bool show)
	Method to be called by derived classes in their SetVisible() implementation. Calls AncestorVisibilityChanged() on the items in this BLayout.

void	ResetLayoutInvalidation ()
	Reset layout invalidation, causing InvalidateLayout calls to proceed again. This method should be called once any cached data has been validated, or updated to valid values.

virtual status_t	AllArchived (BMessage *into) const
	Method relating to the use of `BArchiver`.

virtual status_t	AllUnarchived (const BMessage *from)
	Method relating to the use of `BUnarchiver`.

Hook methods

Detailed Description

The BCardLayout class is a simple BLayout subclass that arranges the items as a stack of cards with only one card being on top and visible to the user.

Once you have set up the items in the container, you can select which one is visible using the SetVisibleItem() methods on this class. When there is no item on top, the system's default grey background is shown.

This view is useful when you have a number of pre-loaded UI elements, and you want to be able to swap between them quickly, while retaining the underlying state. The container itself will retain a fixed size, so from a visual perspective, it is imperative that the items in the stack have comparable dimensions.

An example usage is for a configuration wizard, where the user will need to complete a number of steps to perform an action. Because you want to the user to experience all these steps as a smooth flow within one window, you can set up the individual pages as views, and add these as cards to the card layout. Then you tie the Next and Previous buttons to switch between the visible cards using the BCardLayout::SetVisible() methods.

Since: Haiku R1

Constructor & Destructor Documentation

◆ BCardLayout() [1/2]

BCardLayout::BCardLayout ( )

Create a new card layout.

Since: Haiku R1

◆ BCardLayout() [2/2]

BCardLayout::BCardLayout ( BMessage * from )

Constructs a BCardLayout from an archive message.

This method is usually not called directly, if you want to build a card layout from an archived message you should call Instantiate() instead because it can handle errors properly.

Parameters

from	The BMessage that contains the card layout.

Since: Haiku R1

◆ ~BCardLayout()

BCardLayout::~BCardLayout ( )

virtual

Destructor.

Since: Haiku R1

Member Function Documentation

◆ AllArchived()

status_t BCardLayout::AllArchived ( BMessage * archive ) const

protectedvirtual

Hook method overridden from BArchivable.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ AllUnarchived()

status_t BCardLayout::AllUnarchived ( const BMessage * from )

protectedvirtual

Hook method overridden from BArchivable.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ Archive()

status_t BCardLayout::Archive	(	BMessage *	into,
		bool	deep = `true`
	)		const

virtual

Archive this layout into a BMessage.

Parameters

into	The message to which to archive into.
deep	When `true`, the children of this layout will also be added.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ BaseAlignment()

BAlignment BCardLayout::BaseAlignment ( )

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ BaseMaxSize()

BSize BCardLayout::BaseMaxSize ( )

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ BaseMinSize()

BSize BCardLayout::BaseMinSize ( )

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ BasePreferredSize()

BSize BCardLayout::BasePreferredSize ( )

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ DoLayout()

void BCardLayout::DoLayout ( )

protectedvirtual

Hook method overridden from BAbstractLayout.

Since: Haiku R1

Implements BLayout.

◆ GetHeightForWidth()

void BCardLayout::GetHeightForWidth	(	float	width,
		float *	min,
		float *	max,
		float *	preferred
	)

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BLayoutItem.

◆ HasHeightForWidth()

bool BCardLayout::HasHeightForWidth ( )

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BLayoutItem.

◆ Instantiate()

static BArchivable * BCardLayout::Instantiate ( BMessage * from )

static

Instantiate a BCardLayout object from message from.

Since: Haiku R1

◆ ItemAdded()

bool BCardLayout::ItemAdded	(	BLayoutItem *	item,
		int32	atIndex
	)

protectedvirtual

Hook method overridden from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ ItemArchived()

status_t BCardLayout::ItemArchived	(	BMessage *	into,
		BLayoutItem *	item,
		int32	index
	)		const

protectedvirtual

Hook method overridden from BArchivable.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ ItemRemoved()

void BCardLayout::ItemRemoved	(	BLayoutItem *	item,
		int32	fromIndex
	)

protectedvirtual

Hook method overridden from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ ItemUnarchived()

status_t BCardLayout::ItemUnarchived	(	const BMessage *	from,
		BLayoutItem *	item,
		int32	index
	)

protectedvirtual

Hook method overridden from BArchivable.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ LayoutInvalidated()

void BCardLayout::LayoutInvalidated ( bool children = false )

protectedvirtual

Hook method overridden from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ Perform()

status_t BCardLayout::Perform	(	perform_code	d,
		void *	arg
	)

virtual

Overridden hook method from BAbstractLayout.

Since: Haiku R1

Reimplemented from BAbstractLayout.

◆ SetVisibleItem() [1/2]

void BCardLayout::SetVisibleItem ( BLayoutItem * item )

Set the current visible item to item.

Parameters

item	A pointer to an item that is already added to this layout. When a reference to an item not on the stack, or `NULL` is passed, then no item will be displayed and the view will reset to the default grey background.

Since: Haiku R1

◆ SetVisibleItem() [2/2]

void BCardLayout::SetVisibleItem ( int32 index )

Set the current visible item to the item at index.

Parameters

index This is a zero-based index for the item you want to display. If the item does not exist (it is lower than 0 or it is higher than the number of items), no item will be displayed and the view will reset to the default grey background.

Since: Haiku R1

◆ VisibleIndex()

int32 BCardLayout::VisibleIndex ( ) const

Get the index of the currently visible item.

Returns: Returns the zero-based index, or -1 if there is no item visible.

Since: Haiku R1

◆ VisibleItem()

BLayoutItem * BCardLayout::VisibleItem ( ) const

Get a pointer to the currently visible item.

Returns: This method returns a pointer to the currently visible layout item, or NULL if there is no card visible.

Since: Haiku R1

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ BCardLayout() [1/2]

◆ BCardLayout() [2/2]

◆ ~BCardLayout()

Member Function Documentation

◆ AllArchived()

◆ AllUnarchived()

◆ Archive()

◆ BaseAlignment()

◆ BaseMaxSize()

◆ BaseMinSize()

◆ BasePreferredSize()

◆ DoLayout()

◆ GetHeightForWidth()

◆ HasHeightForWidth()

◆ Instantiate()

◆ ItemAdded()

◆ ItemArchived()

◆ ItemRemoved()

◆ ItemUnarchived()

◆ LayoutInvalidated()

◆ Perform()

◆ SetVisibleItem() [1/2]

◆ SetVisibleItem() [2/2]

◆ VisibleIndex()

◆ VisibleItem()