This container widget lets you maneuver around a set of widgets much larger than your window. More...

#include <Fl_Scroll.H>

Inheritance diagram for Fl_Scroll:

Public Types
enum	{ HORIZONTAL = 1, VERTICAL = 2, BOTH = 3, ALWAYS_ON = 4, HORIZONTAL_ALWAYS = 5, VERTICAL_ALWAYS = 6, BOTH_ALWAYS = 7 }

Public Member Functions
void	clear ()
	Clear all but the scrollbars... More...

	Fl_Scroll (int X, int Y, int W, int H, const char *l=0)
	Creates a new Fl_Scroll widget using the given position, size, and label string. More...

int	handle (int)
	Handles the specified event. More...

void	resize (int, int, int, int)
	Resizes the Fl_Group widget and all of its children. More...

void	scroll_to (int, int)
	Moves the contents of the scroll group to a new position. More...

int	scrollbar_size () const
	Gets the current size of the scrollbars' troughs, in pixels. More...

void	scrollbar_size (int newSize)
	Sets the pixel size of the scrollbars' troughs to `newSize`, in pixels. More...

int	xposition () const
	Gets the current horizontal scrolling position. More...

int	yposition () const
	Gets the current vertical scrolling position. More...

Public Member Functions inherited from Fl_Group
Fl_Widget *&	_ddfdesign_kludge ()
	This is for forms compatibility only.

void	add (Fl_Widget &)
	The widget is removed from its current group (if any) and then added to the end of this group.

void	add (Fl_Widget *o)
	See void Fl_Group::add(Fl_Widget &w)

void	add_resizable (Fl_Widget &o)
	Adds a widget to the group and makes it the resizable widget.

Fl_Widget const	array () const
	Returns a pointer to the array of children. More...

virtual Fl_Group *	as_group ()
	Returns an Fl_Group pointer if this widget is an Fl_Group. More...

void	begin ()
	Sets the current group so you can build the widget tree by just constructing the widgets. More...

Fl_Widget *	child (int n) const
	Returns array()[n]. More...

int	children () const
	Returns how many child widgets the group has.

void	clear ()
	Deletes all child widgets from memory recursively. More...

void	clip_children (int c)
	Controls whether the group widget clips the drawing of child widgets to its bounding box. More...

unsigned int	clip_children ()
	Returns the current clipping mode. More...

void	end ()
	Exactly the same as current(this->parent()). More...

int	find (const Fl_Widget *) const
	Searches the child array for the widget and returns the index. More...

int	find (const Fl_Widget &o) const
	See int Fl_Group::find(const Fl_Widget *w) const.

	Fl_Group (int, int, int, int, const char *=0)
	Creates a new Fl_Group widget using the given position, size, and label string. More...

void	focus (Fl_Widget *W)

void	forms_end ()
	This is for forms compatibility only.

void	init_sizes ()
	Resets the internal array of widget sizes and positions. More...

void	insert (Fl_Widget &, int i)
	The widget is removed from its current group (if any) and then inserted into this group. More...

void	insert (Fl_Widget &o, Fl_Widget *before)
	This does insert(w, find(before)). More...

void	remove (int index)
	Removes the widget at `index` from the group but does not delete it. More...

void	remove (Fl_Widget &)
	Removes a widget from the group but does not delete it. More...

void	remove (Fl_Widget *o)
	Removes the widget `o` from the group. More...

void	resizable (Fl_Widget &o)
	See void Fl_Group::resizable(Fl_Widget *box)

void	resizable (Fl_Widget *o)
	The resizable widget defines the resizing box for the group. More...

Fl_Widget *	resizable () const
	See void Fl_Group::resizable(Fl_Widget *box)

virtual	~Fl_Group ()
	The destructor also deletes all the children. More...

Public Member Functions inherited from Fl_Widget
void	_clear_fullscreen ()

void	_set_fullscreen ()

void	activate ()
	Activates the widget. More...

unsigned int	active () const
	Returns whether the widget is active. More...

int	active_r () const
	Returns whether the widget and all of its parents are active. More...

Fl_Align	align () const
	Gets the label alignment. More...

void	align (Fl_Align alignment)
	Sets the label alignment. More...

long	argument () const
	Gets the current user data (long) argument that is passed to the callback function.

void	argument (long v)
	Sets the current user data (long) argument that is passed to the callback function. More...

virtual class Fl_Gl_Window *	as_gl_window ()
	Returns an Fl_Gl_Window pointer if this widget is an Fl_Gl_Window. More...

virtual Fl_Window *	as_window ()
	Returns an Fl_Window pointer if this widget is an Fl_Window. More...

Fl_Boxtype	box () const
	Gets the box type of the widget. More...

void	box (Fl_Boxtype new_box)
	Sets the box type for the widget. More...

Fl_Callback_p	callback () const
	Gets the current callback function for the widget. More...

void	callback (Fl_Callback cb, void p)
	Sets the current callback function for the widget. More...

void	callback (Fl_Callback *cb)
	Sets the current callback function for the widget. More...

void	callback (Fl_Callback0 *cb)
	Sets the current callback function for the widget. More...

void	callback (Fl_Callback1 *cb, long p=0)
	Sets the current callback function for the widget. More...

unsigned int	changed () const
	Checks if the widget value changed since the last callback. More...

void	clear_active ()
	Marks the widget as inactive without sending events or changing focus. More...

void	clear_changed ()
	Marks the value of the widget as unchanged. More...

void	clear_damage (uchar c=0)
	Clears or sets the damage flags. More...

void	clear_output ()
	Sets a widget to accept input. More...

void	clear_visible ()
	Hides the widget. More...

void	clear_visible_focus ()
	Disables keyboard focus navigation with this widget. More...

Fl_Color	color () const
	Gets the background color of the widget. More...

void	color (Fl_Color bg)
	Sets the background color of the widget. More...

void	color (Fl_Color bg, Fl_Color sel)
	Sets the background and selection color of the widget. More...

Fl_Color	color2 () const
	For back compatibility only. More...

void	color2 (unsigned a)
	For back compatibility only. More...

int	contains (const Fl_Widget *w) const
	Checks if w is a child of this widget. More...

void	copy_label (const char *new_label)
	Sets the current label. More...

void	copy_tooltip (const char *text)
	Sets the current tooltip text. More...

uchar	damage () const
	Returns non-zero if draw() needs to be called. More...

void	damage (uchar c)
	Sets the damage bits for the widget. More...

void	damage (uchar c, int x, int y, int w, int h)
	Sets the damage bits for an area inside the widget. More...

int	damage_resize (int, int, int, int)
	Internal use only. More...

void	deactivate ()
	Deactivates the widget. More...

Fl_Image *	deimage ()
	Gets the image that is used as part of the widget label. More...

const Fl_Image *	deimage () const

void	deimage (Fl_Image *img)
	Sets the image to use as part of the widget label. More...

void	deimage (Fl_Image &img)
	Sets the image to use as part of the widget label. More...

void	do_callback ()
	Calls the widget callback. More...

void	do_callback (Fl_Widget *o, long arg)
	Calls the widget callback. More...

void	do_callback (Fl_Widget o, void arg=0)
	Calls the widget callback. More...

void	draw_label (int, int, int, int, Fl_Align) const
	Draws the label in an arbitrary bounding box with an arbitrary alignment. More...

int	h () const
	Gets the widget height. More...

virtual void	hide ()
	Makes a widget invisible. More...

Fl_Image *	image ()
	Gets the image that is used as part of the widget label. More...

const Fl_Image *	image () const

void	image (Fl_Image *img)
	Sets the image to use as part of the widget label. More...

void	image (Fl_Image &img)
	Sets the image to use as part of the widget label. More...

int	inside (const Fl_Widget *wgt) const
	Checks if this widget is a child of `wgt`. More...

const char *	label () const
	Gets the current label text. More...

void	label (const char *text)
	Sets the current label pointer. More...

void	label (Fl_Labeltype a, const char *b)
	Shortcut to set the label text and type in one call. More...

Fl_Color	labelcolor () const
	Gets the label color. More...

void	labelcolor (Fl_Color c)
	Sets the label color. More...

Fl_Font	labelfont () const
	Gets the font to use. More...

void	labelfont (Fl_Font f)
	Sets the font to use. More...

Fl_Fontsize	labelsize () const
	Gets the font size in pixels. More...

void	labelsize (Fl_Fontsize pix)
	Sets the font size in pixels. More...

Fl_Labeltype	labeltype () const
	Gets the label type. More...

void	labeltype (Fl_Labeltype a)
	Sets the label type. More...

void	measure_label (int &ww, int &hh) const
	Sets width ww and height hh accordingly with the label size. More...

unsigned int	output () const
	Returns if a widget is used for output only. More...

Fl_Group *	parent () const
	Returns a pointer to the parent widget. More...

void	parent (Fl_Group *p)
	Internal use only - "for hacks only". More...

void	position (int X, int Y)
	Repositions the window or widget. More...

void	redraw ()
	Schedules the drawing of the widget. More...

void	redraw_label ()
	Schedules the drawing of the label. More...

Fl_Color	selection_color () const
	Gets the selection color. More...

void	selection_color (Fl_Color a)
	Sets the selection color. More...

void	set_active ()
	Marks the widget as active without sending events or changing focus. More...

void	set_changed ()
	Marks the value of the widget as changed. More...

void	set_output ()
	Sets a widget to output only. More...

void	set_visible ()
	Makes the widget visible. More...

void	set_visible_focus ()
	Enables keyboard focus navigation with this widget. More...

virtual void	show ()
	Makes a widget visible. More...

void	size (int W, int H)
	Changes the size of the widget. More...

int	take_focus ()
	Gives the widget the keyboard focus. More...

unsigned int	takesevents () const
	Returns if the widget is able to take events. More...

int	test_shortcut ()
	Returns true if the widget's label contains the entered '&x' shortcut. More...

const char *	tooltip () const
	Gets the current tooltip text. More...

void	tooltip (const char *text)
	Sets the current tooltip text. More...

Fl_Window *	top_window () const
	Returns a pointer to the top-level window for the widget. More...

Fl_Window *	top_window_offset (int &xoff, int &yoff) const
	Finds the x/y offset of the current widget relative to the top-level window. More...

uchar	type () const
	Gets the widget type. More...

void	type (uchar t)
	Sets the widget type. More...

int	use_accents_menu ()
	Returns non zero if MAC_USE_ACCENTS_MENU flag is set, 0 otherwise.

void *	user_data () const
	Gets the user data for this widget. More...

void	user_data (void *v)
	Sets the user data for this widget. More...

unsigned int	visible () const
	Returns whether a widget is visible. More...

void	visible_focus (int v)
	Modifies keyboard focus navigation. More...

unsigned int	visible_focus ()
	Checks whether this widget has a visible focus. More...

int	visible_r () const
	Returns whether a widget and all its parents are visible. More...

int	w () const
	Gets the widget width. More...

Fl_When	when () const
	Returns the conditions under which the callback is called. More...

void	when (uchar i)
	Sets the flags used to decide when a callback is called. More...

Fl_Window *	window () const
	Returns a pointer to the nearest parent window up the widget hierarchy. More...

int	x () const
	Gets the widget position in its window. More...

int	y () const
	Gets the widget position in its window. More...

virtual	~Fl_Widget ()
	Destroys the widget. More...

Public Attributes
Fl_Scrollbar	hscrollbar

Fl_Scrollbar	scrollbar

Protected Member Functions
void	bbox (int &, int &, int &, int &)
	Returns the bounding box for the interior of the scrolling area, inside the scrollbars. More...

void	draw ()
	Draws the widget. More...

Protected Member Functions inherited from Fl_Group
void	draw_child (Fl_Widget &widget) const
	Forces a child to redraw. More...

void	draw_children ()
	Draws all children of the group. More...

void	draw_outside_label (const Fl_Widget &widget) const
	Parents normally call this to draw outside labels of child widgets. More...

int *	sizes ()
	Returns the internal array of widget sizes and positions. More...

void	update_child (Fl_Widget &widget) const
	Draws a child only if it needs it. More...

Protected Member Functions inherited from Fl_Widget
void	clear_flag (unsigned int c)
	Clears a flag in the flags mask.

void	draw_backdrop () const
	If FL_ALIGN_IMAGE_BACKDROP is set, the image or deimage will be drawn.

void	draw_box () const
	Draws the widget box according its box style.

void	draw_box (Fl_Boxtype t, Fl_Color c) const
	Draws a box of type t, of color c at the widget's position and size. More...

void	draw_box (Fl_Boxtype t, int x, int y, int w, int h, Fl_Color c) const
	Draws a box of type t, of color c at the position X,Y and size W,H. More...

void	draw_focus ()
	draws a focus rectangle around the widget

void	draw_focus (Fl_Boxtype t, int x, int y, int w, int h) const
	Draws a focus box for the widget at the given position and size.

void	draw_label () const
	Draws the widget's label at the defined label position. More...

void	draw_label (int, int, int, int) const
	Draws the label in an arbitrary bounding box. More...

	Fl_Widget (int x, int y, int w, int h, const char *label=0L)
	Creates a widget at the given position and size. More...

unsigned int	flags () const
	Gets the widget flags mask.

void	h (int v)
	Internal use only. More...

void	set_flag (unsigned int c)
	Sets a flag in the flags mask.

void	w (int v)
	Internal use only. More...

void	x (int v)
	Internal use only. More...

void	y (int v)
	Internal use only. More...

Additional Inherited Members
Static Public Member Functions inherited from Fl_Group
static Fl_Group *	current ()
	Returns the currently active group. More...

static void	current (Fl_Group *g)
	Sets the current group. More...

Static Public Member Functions inherited from Fl_Widget
static void	default_callback (Fl_Widget cb, void d)
	Sets the default callback for all widgets. More...

static unsigned int	label_shortcut (const char *t)
	Returns the Unicode value of the '&x' shortcut in a given text. More...

static int	test_shortcut (const char *, const bool require_alt=false)
	Returns true if the given text `t` contains the entered '&x' shortcut. More...

Protected Types inherited from Fl_Widget
enum	{ INACTIVE = 1<<0, INVISIBLE = 1<<1, OUTPUT = 1<<2, NOBORDER = 1<<3, FORCE_POSITION = 1<<4, NON_MODAL = 1<<5, SHORTCUT_LABEL = 1<<6, CHANGED = 1<<7, OVERRIDE = 1<<8, VISIBLE_FOCUS = 1<<9, COPIED_LABEL = 1<<10, CLIP_CHILDREN = 1<<11, MENU_WINDOW = 1<<12, TOOLTIP_WINDOW = 1<<13, MODAL = 1<<14, NO_OVERLAY = 1<<15, GROUP_RELATIVE = 1<<16, COPIED_TOOLTIP = 1<<17, FULLSCREEN = 1<<18, MAC_USE_ACCENTS_MENU = 1<<19, USERFLAG3 = 1<<29, USERFLAG2 = 1<<30, USERFLAG1 = 1<<31 }
	flags possible values enumeration. More...

Detailed Description

This container widget lets you maneuver around a set of widgets much larger than your window.

If the child widgets are larger than the size of this object then scrollbars will appear so that you can scroll over to them:

If all of the child widgets are packed together into a solid rectangle then you want to set box() to FL_NO_BOX or one of the _FRAME types. This will result in the best output. However, if the child widgets are a sparse arrangement you must set box() to a real _BOX type. This can result in some blinking during redrawing, but that can be solved by using a Fl_Double_Window.

By default you can scroll in both directions, and the scrollbars disappear if the data will fit in the area of the scroll.

Use Fl_Scroll::type() to change this as follows :

0 - No scrollbars
Fl_Scroll::HORIZONTAL - Only a horizontal scrollbar.
Fl_Scroll::VERTICAL - Only a vertical scrollbar.
Fl_Scroll::BOTH - The default is both scrollbars.
Fl_Scroll::HORIZONTAL_ALWAYS - Horizontal scrollbar always on, vertical always off.
Fl_Scroll::VERTICAL_ALWAYS - Vertical scrollbar always on, horizontal always off.
Fl_Scroll::BOTH_ALWAYS - Both always on.

Use scrollbar.align(int) ( see void Fl_Widget::align(Fl_Align) ) : to change what side the scrollbars are drawn on.

If the FL_ALIGN_LEFT bit is on, the vertical scrollbar is on the left. If the FL_ALIGN_TOP bit is on, the horizontal scrollbar is on the top. Note that only the alignment flags in scrollbar are considered. The flags in hscrollbar however are ignored.

This widget can also be used to pan around a single child widget "canvas". This child widget should be of your own class, with a draw() method that draws the contents. The scrolling is done by changing the x() and y() of the widget, so this child must use the x() and y() to position its drawing. To speed up drawing it should test fl_push_clip().

Another very useful child is a single Fl_Pack, which is itself a group that packs its children together and changes size to surround them. Filling the Fl_Pack with Fl_Tabs groups (and then putting normal widgets inside those) gives you a very powerful scrolling list of individually-openable panels.

Fluid lets you create these, but you can only lay out objects that fit inside the Fl_Scroll without scrolling. Be sure to leave space for the scrollbars, as Fluid won't show these either.

You cannot use Fl_Window as a child of this since the clipping is not conveyed to it when drawn, and it will draw over the scrollbars and neighboring objects.

Constructor & Destructor Documentation

Fl_Scroll::Fl_Scroll	(	int	X,
		int	Y,
		int	W,
		int	H,
		const char *	L = `0`
	)

Creates a new Fl_Scroll widget using the given position, size, and label string.

The default boxtype is FL_NO_BOX.

The destructor also deletes all the children. This allows a whole tree to be deleted at once, without having to keep a pointer to all the children in the user code. A kludge has been done so the Fl_Scroll and all of its children can be automatic (local) variables, but you must declare the Fl_Scroll first, so that it is destroyed last.

Member Function Documentation

void Fl_Scroll::bbox	(	int &	X,
		int &	Y,
		int &	W,
		int &	H
	)

protected

Returns the bounding box for the interior of the scrolling area, inside the scrollbars.

Currently this is only reliable after draw(), and before any resizing of the Fl_Scroll or any child widgets occur.

Todo:: The visibility of the scrollbars ought to be checked/calculated outside of the draw() method (STR #1895).

void Fl_Scroll::clear ( )

Clear all but the scrollbars...

void Fl_Scroll::draw ( )

protectedvirtual

Draws the widget.

Never call this function directly. FLTK will schedule redrawing whenever needed. If your widget must be redrawn as soon as possible, call redraw() instead.

Override this function to draw your own widgets.

If you ever need to call another widget's draw method from within your own draw() method, e.g. for an embedded scrollbar, you can do it (because draw() is virtual) like this:

Fl_Widget *s = &scroll; // scroll is an embedded Fl_Scrollbar

s->draw(); // calls Fl_Scrollbar::draw()

Reimplemented from Fl_Group.

int Fl_Scroll::handle ( int event )

virtual

Handles the specified event.

You normally don't call this method directly, but instead let FLTK do it when the user interacts with the widget.

When implemented in a widget, this function must return 0 if the widget does not use the event or 1 otherwise.

Most of the time, you want to call the inherited handle() method in your overridden method so that you don't short-circuit events that you don't handle. In this last case you should return the callee retval.

Parameters

[in] event the kind of event received

Return values

0	if the event was not used or understood
1	if the event was used and can be deleted

See Also: Fl_Event

Reimplemented from Fl_Group.

void Fl_Scroll::resize	(	int	X,
		int	Y,
		int	W,
		int	H
	)

virtual

Resizes the Fl_Group widget and all of its children.

The Fl_Group widget first resizes itself, and then it moves and resizes all its children according to the rules documented for Fl_Group::resizable(Fl_Widget*)

See Also: Fl_Group::resizable(Fl_Widget*); Fl_Group::resizable(); Fl_Widget::resize(int,int,int,int)

Reimplemented from Fl_Group.

void Fl_Scroll::scroll_to	(	int	X,
		int	Y
	)

Moves the contents of the scroll group to a new position.

int Fl_Scroll::scrollbar_size ( ) const

inline

Gets the current size of the scrollbars' troughs, in pixels.

If this value is zero (default), this widget will use the Fl::scrollbar_size() value as the scrollbar's width.

Returns: Scrollbar size in pixels, or 0 if the global Fl::scrollsize() is being used.

See Also: Fl::scrollbar_size(int)

void Fl_Scroll::scrollbar_size ( int newSize )

inline

Sets the pixel size of the scrollbars' troughs to newSize, in pixels.

Normally you should not need this method, and should use Fl::scrollbar_size(int) instead to manage the size of ALL your widgets' scrollbars. This ensures your application has a consistent UI, is the default behavior, and is normally what you want.

Only use THIS method if you really need to override the global scrollbar size. The need for this should be rare.

Setting newSize to the special value of 0 causes the widget to track the global Fl::scrollbar_size(), which is the default.

Parameters

[in] newSize Sets the scrollbar size in pixels.
If 0 (default), scrollbar size tracks the global Fl::scrollbar_size()

See Also: Fl::scrollbar_size()

int Fl_Scroll::xposition ( ) const

inline

Gets the current horizontal scrolling position.

int Fl_Scroll::yposition ( ) const

inline

Gets the current vertical scrolling position.

The documentation for this class was generated from the following files:

Fl_Scroll.H
Fl_Scroll.cxx

Public Types

Public Member Functions

Public Attributes

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation