haiku/docs/user/interface/Box.dox

/*
 * Copyright 2010, Haiku inc.
 * Distributed under the terms of the MIT Licence.
 *
 * Documentation by:
 *  Clark Gaeble
 *  Adrien Destugues <pulkomandy@pulkomandy.ath.cx>
 * Corresponds to:
 *  /trunk/headers/os/interface/Box.h  rev 39685
 *  /trunk/src/kits/interface/Box.cpp  rev 39685

/*!
\file Box.h
\brief Defines the BBox class
*/

/*! \class BBox
	\ingroup interface
	\brief Class just drawing a square box with a label in a window.
	
	A Box represents a square on the interface with dimensions, an optional
	name, and no interactivity.

	This would be used to visually group elements together.
*/

/*! \fn BBox::BBox(BRect frame, const char *name = NULL, uint32 resizingMode = B_FOLLOW_LEFT | B_FOLLOW_TOP, uint32 flags = B_WILL_DRAW | B_FRAME_EVENTS | B_NAVIGABLE_JUMP, border_style border = B_FANCY_BORDER)
	\brief Constructs a Box from a set of dimensions.

	This is the only constructor that can be used if the box is to be inserted
	in a window that doesn't use the layout system.

	\param frame        The bounds of the box.
	\param name         The name of the box.
	\param resizingMode Defines the behavior of the box as the parent view
		resizes.
	\param flags        Behavior flags for the box. See BView page for more
		info.
	\param border       Sets the initial style of the border. See SetBorder for
		more details.
*/


/*! \fn BBox::BBox(const char* name, uint32 flags = B_WILL_DRAW | B_FRAME_EVENTS | B_NAVIGABLE_JUMP, border_style border = B_FANCY_BORDER, BView* child = NULL)
	\brief Constructs a named Box, with dimensions defined automatically by the
		Layout Kit.

	\param name   The name of the box.
	\param flags  Behavior flags for the box.
	\param border Defines the initial border style.
	\param child  Adds an initial child to the box. See: Layout Kit
*/


/*! \fn BBox::BBox(border_style border, BView* child)
	\brief Constructs an anonymous Box, with a defined border style and a child.

	There can only be a single child view in the box. This view can, however,
	act as a nesting container if you need more things to show inside the box.

	\param border The initial border style of the box.
	\param child  The child of the Box.
*/


/*! \fn BBox::BBox(BMessage* archive)
	\brief For archive restoration, allows a box to be constructed from an
		archive message.

	You don't usually call this directly, if you want to build a BBox from a
	message, prefer calling Instantiate, which can properly handle errors.

	If the archive is a deep one, the box will also unarchive all of its
	children recursively.

	\param archive  The archive to restore from.
*/


/*! \fn static BArchivable*	BBox::Instantiate(BMessage* archive)
	\brief Creates a new BBox from an archive.

	If the message is a valid box, an instance of BBox (created from the
	archive) will be returned. Otherwise, this function will return NULL.
*/


/*! \fn virtual	status_t BBox::Archive(BMessage* archive, bool deep = true) const;
	\brief Archives the box into archive.

	\param   archive The target archive which the box data will go into.
	\param   deep    Whether or not to recursively archive the children.
	\returns B_OK if the archive was successful.
*/


/*! \fn virtual	void BBox::SetBorder(border_style border)
	\brief Sets the border style.

	Possible values are B_PLAIN_BORDER (a single 1-pixel line border),
	B_FANCY_BORDER (the default, slightly beveled look), and B_NO_BORDER, which
	is used to make an invisible box.
*/


/*! \fn border_style BBox::Border() const
	\brief Gets the border style.
*/


/*! \fn float BBox::TopBorderOffset()
	\brief Gets the distance from the very top of the Box to the top border
		line, in pixels.

	The distance may vary depending on the text or view used as label, and the
	font settings. The border is drawn center aligned with the label.

	You can use this value to line up two boxes visually, if one has a label and
	the other has not.
*/


/*! \fn BRect BBox::InnerFrame()
	\brief Returns the rectangle just inside the border.
*/


/*! \fn void BBox::SetLabel(const char* string)
	\brief Sets the label's text.

	This text is shown as the box title on screen, so the user can identify the
	purpose of it.
*/


/*! \fn status_t BBox::SetLabel(BView* viewLabel)
	\brief Sets the label from a pre-existing BView.

	You can use any type of BView for this, such as a BPopupMenu.
	This version of SetLabel is much more powerful than
	SetLabel(const char* string). It allows building a box which contents can
	be changed depending on the label widget.
*/


/*! \fn const char*	BBox::Label() const
	\brief Gets the label's text.

	This only works if the label was set as text. If you set another view as the
	label, you have to get its text by other means, likely starting with
	LabelView.
*/


/*! \fn BView*	BBox::LabelView() const
	\brief Gets the BView representing the label.
*/


/*! \fn virtual	void BBox::Draw(BRect updateRect)
	\brief Draws onto the parent window the part of the box that intersects
		the dirty area.

	This is an hook function called by the interface kit. You don't have to call
	it yourself. If you need to force redrawing of (part of) the box, consider
	using Invalidate instead.

	\param updateRect The area that needs to be redrawn. Note the box may draw
		more around the rectangle.
*/


/*! \fn virtual	void BBox::AttachedToWindow()
	\brief Hook called when the box is attached to a window.

	This function sets the box background color to the parent's one.

	If you are using the layout system, the box is also resized depending
	on the layout of the parent view.
*/


/*! \fn virtual void BBox::FrameResized(float width, float height)
	\brief Called when the box needs to change its size.

	This function may be called either because the window in which the box is
	was resized, or because the window layout was otherwise altered.

	It recomputes the layouting of the box (including label and contents) and
	makes it redraw itself as needed.
*/


/*! \fn 	virtual void BBox::ResizeToPreferred()
	\brief Resizes the box to its preferred dimensions.

	This only works in the non-layout mode, as it forces the resizing.
*/


/*!	\fn virtual void BBox::GetPreferredSize(float* _width, float* _height)
	\brief Gets the dimensions the box would prefer to be.

	The size is computed from the children sizes, unless it was explicitly set
	for the box (which canbe done only in layouted mode).

	\note Either one of the parameters may be set to NULL if you only want to
		get the other one.

	\param _width  An output parameter. The width of the preferred size is
		placed in here.
	\param _height An output parameter. The height of the preferred size is
		placed in here.
*/


/*! \fn virtual	BSize BBox::MinSize()
	\brief Gets the minimum possible size of the Box.

	Drawing the box at this size ensures the label and the child view are
	visible. Going smaller means something may get invisible on screen for lack
	of space.
*/


/*!	\fn virtual	BSize BBox::MaxSize()
	\brief Gets the maximum possible size of the Box.

	The maximum size depends on the child view's one.
*/


/*! \fn virtual	BSize BBox::PreferredSize()
	\brief Returns the box's preferred size.

	This is the same as GetPreferredSize, but using the more convenient BSize
	struct.
*/


/*! \fn virtual	void BBox::DoLayout()
	\brief Lays out the box. Moves everything to its appropriate position.

	This only works if the box uses the layout system, ie., was created with
	one of the BRect-less constructors.

	Once the size of the box is known, from layouting of the parent views, this
	function is called so the box can adjust the position and size of the label,
	eventually truncating the text if there is not enough space. The exact
	border positions are also computed, then the child view is also layouted if
	its size constraints changed.
*/