This widget produces an actual window. More...

#include <Fl_Window.H>

Inheritance diagram for Fl_Window:

Public Types
typedef struct HICON__ *	HICON

Public Member Functions
virtual class Fl_Double_Window *	as_double_window ()
	Return non-null if this is an Fl_Double_Window object.

virtual class Fl_Overlay_Window *	as_overlay_window ()
	Return non-null if this is an Fl_Overlay_Window object.

Fl_Window const *	as_window () const FL_OVERRIDE

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

unsigned int	border () const
	Returns whether the window possesses a border.

void	border (int b)
	Sets whether or not the window manager border is around the window.

void	clear_border ()
	Fast inline function to turn the window manager border off.

void	clear_modal_states ()
	Clears the "modal" flags and converts a "modal" or "non-modal" window back into a "normal" window.

void	copy_label (const char *a)
	Sets the window titlebar label to a copy of a character string.

void	cursor (const Fl_RGB_Image *, int, int)
	Changes the cursor for this window using the provided image as cursor's shape.

void	cursor (Fl_Cursor c, Fl_Color, Fl_Color=FL_WHITE)
	For back compatibility only.

void	cursor (Fl_Cursor)
	Changes the cursor for this window.

int	decorated_h () const
	Returns the window height including any window title bar and any frame added by the window manager.

int	decorated_w () const
	Returns the window width including any frame added by the window manager.

void	default_cursor (Fl_Cursor c, Fl_Color, Fl_Color=FL_WHITE)
	For back compatibility only.

void	default_cursor (Fl_Cursor)
	Sets the default window cursor.

void	draw_backdrop ()
	Draw the background image if one is set and is aligned inside.

	Fl_Window (int w, int h, const char *title=0)
	Creates a window from the given width `w`, height `h`, and `title`.

	Fl_Window (int x, int y, int w, int h, const char *title=0)
	Creates a window from the given position (x, y), size (w, h) and title.

void	free_position ()
	Undoes the effect of a previous resize() or show() so that the next time show() is called the window manager is free to position the window.

void	fullscreen ()
	Makes the window completely fill one or more screens, without any window manager border visible.

unsigned int	fullscreen_active () const
	Returns non zero if FULLSCREEN flag is set, 0 otherwise.

void	fullscreen_off ()
	Turns off any side effects of fullscreen()

void	fullscreen_off (int X, int Y, int W, int H)
	Turns off any side effects of fullscreen() and does resize(x,y,w,h).

void	fullscreen_screens (int top, int bottom, int left, int right)
	Sets which screens should be used when this window is in fullscreen mode.

int	handle (int) FL_OVERRIDE
	Handles the specified event.

void	hide () FL_OVERRIDE
	Removes the window from the screen.

void	hotspot (const Fl_Widget &p, int offscreen=0)
	See void Fl_Window::hotspot(int x, int y, int offscreen = 0)

void	hotspot (const Fl_Widget *, int offscreen=0)
	See void Fl_Window::hotspot(int x, int y, int offscreen = 0)

void	hotspot (int x, int y, int offscreen=0)
	Positions the window so that the mouse is pointing at the given position, or at the center of the given widget, which may be the window itself.

const void *	icon () const
	Gets the current icon window target dependent data.

void	icon (const Fl_RGB_Image *)
	Sets or resets a single window icon.

void	icon (const void *ic)
	Platform-specific method to set the window icon usable on Windows and X11 only.

void	iconize ()
	Iconifies the window.

const char *	iconlabel () const
	See void Fl_Window::iconlabel(const char*)

void	iconlabel (const char *)
	Sets the icon label.

void	icons (const Fl_RGB_Image *[], int)
	Sets the window icons.

void	icons (HICON big_icon, HICON small_icon)
	Sets the window icons using HICON handles (Windows platform only).

const char *	label () const
	See void Fl_Window::label(const char*)

void	label (const char *)
	Sets the window title bar label.

void	label (const char label, const char iconlabel)
	Sets the icon label.

void	make_current ()
	Sets things up so that the drawing functions in <FL/fl_draw.H> will go into this window.

void	maximize ()
	Maximizes a top-level window to its current screen.

unsigned int	maximize_active () const
	Returns whether the window is currently maximized.

unsigned int	menu_window () const
	Returns true if this window is a menu window.

unsigned int	modal () const
	Returns true if this window is modal.

unsigned int	non_modal () const
	Returns true if this window is modal or non-modal.

fl_uintptr_t	os_id ()
	Returns a platform-specific identification of a shown window, or 0 if not shown.

unsigned int	override () const
	Returns non zero if OVERRIDE flag is set, 0 otherwise.

void	resize (int X, int Y, int W, int H) FL_OVERRIDE
	Changes the size and position of the window.

int	screen_num ()
	The number of the screen containing the mapped window.

void	screen_num (int screen_num)
	Set the number of the screen where to map the window.

void	set_menu_window ()
	Marks the window as a menu window.

void	set_modal ()
	A "modal" window, when shown(), will prevent any events from being delivered to other windows in the same program, and will also remain on top of the other windows (if the X window manager supports the "transient for" property).

void	set_non_modal ()
	A "non-modal" window (terminology borrowed from Microsoft Windows) acts like a modal() one in that it remains on top, but it has no effect on event delivery.

void	set_override ()
	Activates the flags NOBORDER\|OVERRIDE.

void	set_tooltip_window ()
	Marks the window as a tooltip window.

const Fl_Image *	shape ()
	Returns the image controlling the window shape or NULL.

void	shape (const Fl_Image &b)
	Set the window's shape with an Fl_Image.

void	shape (const Fl_Image *img)
	Assigns a non-rectangular shape to the window.

void	show () FL_OVERRIDE
	Puts the window on the screen.

void	show (int argc, char **argv)
	Puts the window on the screen with show() and parses command-line arguments.

int	shown ()
	Returns non-zero if show() has been called (but not hide() ).

void	size_range (int minw, int minh, int maxw=0, int maxh=0, int dw=0, int dh=0, int aspect=0)
	Sets the allowable range the user can resize this window to.

unsigned int	tooltip_window () const
	Returns true if this window is a tooltip window.

void	un_maximize ()
	Returns a previously maximized top-level window to its previous size.

void	wait_for_expose ()
	Waits for the window to be displayed after calling show().

int	x_root () const
	Gets the x position of the window on the screen.

const char *	xclass () const
	Returns the xclass for this window, or a default.

void	xclass (const char *c)
	Sets the xclass for this window.

int	y_root () const
	Gets the y position of the window on the screen.

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

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.

Fl_Group const *	as_group () const FL_OVERRIDE

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

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

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

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

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

unsigned int	clip_children ()
	Returns the current clipping mode.

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

virtual int	delete_child (int n)
	Removes the widget at `index` from the group and deletes it.

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

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

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

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

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.

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

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

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

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

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

Fl_Widget *	resizable () const
	Returns the group's resizable widget.

void	resizable (Fl_Widget &o)
	Sets the group's resizable widget.

void	resizable (Fl_Widget *o)
	The resizable widget defines both the resizing box and the resizing behavior of the group and its children.

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

Public Member Functions inherited from Fl_Widget
void	_clear_fullscreen ()

void	_set_fullscreen ()

void	activate ()
	Activates the widget.

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

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

Fl_Align	align () const
	Gets the label alignment.

void	align (Fl_Align alignment)
	Sets the label alignment.

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.

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

virtual class Fl_Gl_Window const *	as_gl_window () const

void	bind_deimage (Fl_Image *img)
	Sets the image to use as part of the widget label when in the inactive state.

void	bind_deimage (int f)
	Bind the inactive image to the widget, so the widget will delete the image when it is no longer needed.

void	bind_image (Fl_Image *img)
	Sets the image to use as part of the widget label when in the active state.

void	bind_image (int f)
	Bind the image to the widget, so the widget will delete the image when it is no longer needed.

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

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

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

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

void	callback (Fl_Callback cb, Fl_Callback_User_Data p, bool auto_free)
	Sets the current callback function and managed user data for the widget.

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

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

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

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

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

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

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

void	clear_output ()
	Sets a widget to accept input.

void	clear_visible ()
	Hides the widget.

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

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

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

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

Fl_Color	color2 () const
	For back compatibility only.

void	color2 (unsigned a)
	For back compatibility only.

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

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

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

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

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

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

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

void	deactivate ()
	Deactivates the widget.

Fl_Image *	deimage ()
	Gets the image that is used as part of the widget label when in the inactive state.

const Fl_Image *	deimage () const
	Gets the image that is used as part of the widget label when in the inactive state.

void	deimage (Fl_Image &img)
	Sets the image to use as part of the widget label when in the inactive state.

void	deimage (Fl_Image *img)
	Sets the image to use as part of the widget label when in the inactive state.

int	deimage_bound () const
	Returns whether the inactive image is managed by the widget.

void	do_callback (Fl_Callback_Reason reason=FL_REASON_UNKNOWN)
	Calls the widget callback function with default arguments.

void	do_callback (Fl_Widget *widget, long arg, Fl_Callback_Reason reason=FL_REASON_UNKNOWN)
	Calls the widget callback function with arbitrary arguments.

void	do_callback (Fl_Widget widget, void arg=0, Fl_Callback_Reason reason=FL_REASON_UNKNOWN)
	Calls the widget callback function with arbitrary arguments.

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

int	h () const
	Gets the widget height.

Fl_Image *	image ()
	Gets the image that is used as part of the widget label when in the active state.

const Fl_Image *	image () const
	Gets the image that is used as part of the widget label when in the active state.

void	image (Fl_Image &img)
	Sets the image to use as part of the widget label when in the active state.

void	image (Fl_Image *img)
	Sets the image to use as part of the widget label when in the active state.

int	image_bound () const
	Returns whether the image is managed by the widget.

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

int	is_label_copied () const
	Returns whether the current label was assigned with copy_label().

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

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

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

Fl_Color	labelcolor () const
	Gets the label color.

void	labelcolor (Fl_Color c)
	Sets the label color.

Fl_Font	labelfont () const
	Gets the font to use.

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

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

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

Fl_Labeltype	labeltype () const
	Gets the label type.

void	labeltype (Fl_Labeltype a)
	Sets the label type.

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

bool	needs_keyboard () const
	Returns whether this widget needs a keyboard.

void	needs_keyboard (bool needs)
	Sets whether this widget needs a keyboard.

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

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

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

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

void	redraw ()
	Schedules the drawing of the widget.

void	redraw_label ()
	Schedules the drawing of the label.

Fl_Color	selection_color () const
	Gets the selection color.

void	selection_color (Fl_Color a)
	Sets the selection color.

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

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

void	set_output ()
	Sets a widget to output only.

void	set_visible ()
	Makes the widget visible.

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

int	shortcut_label () const
	Returns whether the widget's label uses '&' to indicate shortcuts.

void	shortcut_label (int value)
	Sets whether the widget's label uses '&' to indicate shortcuts.

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

int	take_focus ()
	Gives the widget the keyboard focus.

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

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

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

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

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

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.

uchar	type () const
	Gets the widget type.

void	type (uchar t)
	Sets the widget type.

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.

void	user_data (Fl_Callback_User_Data *v, bool auto_free)
	Sets the user data for this widget.

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

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

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

void	visible_focus (int v)
	Modifies keyboard focus navigation.

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

int	w () const
	Gets the widget width.

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

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

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

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

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

virtual	~Fl_Widget ()
	Destroys the widget.

Static Public Member Functions
static Fl_Window *	current ()
	Returns the last window that was made current.

static void	default_callback (Fl_Window , void v)
	Back compatibility: Sets the default callback v for win to call on close event.

static void	default_icon (const Fl_RGB_Image *)
	Sets a single default window icon.

static void	default_icons (const Fl_RGB_Image *[], int)
	Sets the default window icons.

static void	default_icons (HICON big_icon, HICON small_icon)
	Sets the default window icons (Windows platform only).

static const char *	default_xclass ()
	Returns the default xclass.

static void	default_xclass (const char *)
	Sets the default window xclass.

static bool	is_a_rescale ()
	Returns true when a window is being rescaled.

static char	show_next_window_iconic ()
	Returns the static flag whether the next window should be opened iconified.

static void	show_next_window_iconic (char stat)
	Sets a static flag whether the next window should be opened iconified.

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

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

Static Public Member Functions inherited from Fl_Widget
static void	default_callback (Fl_Widget widget, void data)
	The default callback for all widgets that don't set a callback.

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

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

Protected Member Functions
void	default_size_range ()
	Protected method to calculate the default size range of a window.

void	draw () FL_OVERRIDE
	Draws the widget.

virtual void	flush ()
	Forces the window to be drawn, this window is also made current and calls draw().

int	force_position () const
	Returns the internal state of the window's FORCE_POSITION flag.

void	force_position (int force)
	Sets an internal flag that tells FLTK and the window manager to honor position requests.

void	free_icons ()
	Deletes all icons previously attached to the window.

int	is_resizable ()
	Protected method to determine whether a window is resizable.

Protected Member Functions inherited from Fl_Group
Fl_Rect *	bounds ()
	Returns the internal array of widget sizes and positions.

void	draw_child (Fl_Widget &widget) const
	Forces a child to redraw.

void	draw_children ()
	Draws all children of the group.

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

virtual int	on_insert (Fl_Widget *, int)
	Allow derived groups to act when a widget is added as a child.

virtual int	on_move (int, int)
	Allow derived groups to act when a widget is moved within the group.

virtual void	on_remove (int)
	Allow derived groups to act when a child widget is removed from the group.

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

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

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.

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.

void	draw_focus () const
	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 rectangle around the widget.

void	draw_focus (Fl_Boxtype t, int x, int y, int w, int h, Fl_Color bg) 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.

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

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

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

void	h (int v)
	Internal use only.

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

void	w (int v)
	Internal use only.

void	x (int v)
	Internal use only.

void	y (int v)
	Internal use only.

Static Protected Attributes
static Fl_Window *	current_
	Stores the last window that was made current.

Friends
class	Fl_Window_Driver

class	Fl_X

Additional Inherited Members
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 , NEEDS_KEYBOARD = 1<<20 , IMAGE_BOUND = 1<<21 , DEIMAGE_BOUND = 1<<22 , AUTO_DELETE_USER_DATA = 1<<23 , MAXIMIZED = 1<<24 , POPUP = 1<<25 , USERFLAG3 = 1<<29 , USERFLAG2 = 1<<30 , USERFLAG1 = 1<<31 }
	flags possible values enumeration. More...

Detailed Description

This widget produces an actual window.

This can either be a main window, with a border and title and all the window management controls, or a "subwindow" inside a window. This is controlled by whether or not the window has a parent().

Once you create a window, you usually add children Fl_Widget's to it by using window->add(child) for each new widget. See Fl_Group for more information on how to add and remove children.

There are several subclasses of Fl_Window that provide double-buffering, overlay, menu, and OpenGL support.

The window's callback is done if the user tries to close a window using the window manager and Fl::modal() is zero or equal to the window. Fl_Window has a default callback that calls Fl_Window::hide(). Callback reasons can be FL_REASON_CANCELLED if the Escape key was pressed, or FL_REASON_CLOSED when the close button is clicked. FL_WHEN_... flags are ignored.

Constructor & Destructor Documentation

◆ Fl_Window() [1/2]

Fl_Window::Fl_Window	(	int	w,
		int	h,
		const char *	title = `0`
	)

Creates a window from the given width w, height h, and title.

If Fl_Group::current() is not NULL, the window is created as a subwindow of the parent window.

The (w, h) form of the constructor creates a top-level window and asks the window manager to position the window. The (x, y, w, h) form of the constructor either creates a subwindow or a top-level window at the specified location (x, y), subject to window manager configuration. If you do not specify the position of the window, the window manager will pick a place to show the window or allow the user to pick a location. Use position(x, y) or hotspot() before calling show() to request a position on the screen. See Fl_Window::resize() for some more details on positioning windows.

Top-level windows initially have visible() set to 0 and parent() set to NULL. Subwindows initially have visible() set to 1 and parent() set to the parent window pointer.

Fl_Widget::box() defaults to FL_FLAT_BOX. If you plan to completely fill the window with children widgets you should change this to FL_NO_BOX. If you turn the window border off you may want to change this to FL_UP_BOX.

See also: Fl_Window(int x, int y, int w, int h, const char *title)

◆ Fl_Window() [2/2]

Fl_Window::Fl_Window	(	int	x,
		int	y,
		int	w,
		int	h,
		const char *	title = `0`
	)

Creates a window from the given position (x, y), size (w, h) and title.

On a multi-screen system, the values computed by Fl::screen_xywh(int &X, int &Y, int &W, int &H, int n) can be used to discover the coordinates of the area of screen #n. When these screens have various scale factor values, an (x, y) pair may not be enough to specify the targeted screen for the window, because the same (x,y) pair can belong to several screens. In that situation, a call to Fl_Window::screen_num(int) is to be used to identify unambiguously the targeted screen.

See also: Fl_Window(int w, int h, const char *title); Fl::screen_xywh(int &X, int &Y, int &W, int &H, int n)

Note: Under Wayland, it's generally not possible for the client app to control the position of a window in the system. It's only possible to specify on what screen should the compositor place a fullscreen window.

◆ ~Fl_Window()

Fl_Window::~Fl_Window ( )

virtual

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_Window and all of its children can be automatic (local) variables, but you must declare the Fl_Window first so that it is destroyed last.

Member Function Documentation

◆ as_double_window()

virtual class Fl_Double_Window * Fl_Window::as_double_window ( )

inlinevirtual

Return non-null if this is an Fl_Double_Window object.

Reimplemented in Fl_Double_Window.

◆ as_overlay_window()

virtual class Fl_Overlay_Window * Fl_Window::as_overlay_window ( )

inlinevirtual

Return non-null if this is an Fl_Overlay_Window object.

Reimplemented in Fl_Overlay_Window.

◆ as_window() [1/2]

Fl_Window const * Fl_Window::as_window ( ) const

inlinevirtual

Reimplemented from Fl_Widget.

◆ as_window() [2/2]

Fl_Window * Fl_Window::as_window ( )

inlinevirtual

Returns an Fl_Window pointer if this widget is an Fl_Window.

Use this method if you have a widget (pointer) and need to know whether this widget is derived from Fl_Window. If it returns non-NULL, then the widget in question is derived from Fl_Window, and you can use the returned pointer to access its children or other Fl_Window-specific methods.

Return values

NULL	if this widget is not derived from Fl_Window.

Note: This method is provided to avoid dynamic_cast.

See also: Fl_Widget::as_group(), Fl_Widget::as_gl_window()

Reimplemented from Fl_Widget.

◆ border()

void Fl_Window::border ( int b )

Sets whether or not the window manager border is around the window.

The default value is true. With some X window managers, this does not work after show() has been called.

◆ clear_border()

void Fl_Window::clear_border ( )

inline

Fast inline function to turn the window manager border off.

It only works before show() is called.

◆ clear_modal_states()

void Fl_Window::clear_modal_states ( )

inline

Clears the "modal" flags and converts a "modal" or "non-modal" window back into a "normal" window.

Note that there are three states for a window: modal, non-modal, and normal.

You can not change the "modality" of a window whilst it is shown, so it is necessary to first hide() the window, change its "modality" as required, then re-show the window for the new state to take effect.

This method can also be used to change a "modal" window into a "non-modal" one. On several supported platforms, the "modal" state over-rides the "non-modal" state, so the "modal" state must be cleared before the window can be set into the "non-modal" state. In general, the following sequence should work:

win->hide();
win->clear_modal_states();
// Set win to new state as desired, or leave "normal", e.g...
win->set_non_modal();
win->show();

Note: Under some window managers, the sequence of hiding the window and changing its modality will often cause it to be re-displayed at a different position when it is subsequently shown. This is an irritating feature but appears to be unavoidable at present. As a result we would advise to use this method only when absolutely necessary.

See also: void set_modal(), void set_non_modal()

◆ current()

Fl_Window * Fl_Window::current ( )

static

Returns the last window that was made current.

See also: Fl_Window::make_current()

◆ cursor() [1/3]

void Fl_Window::cursor	(	const Fl_RGB_Image *	image,
		int	hotx,
		int	hoty
	)

Changes the cursor for this window using the provided image as cursor's shape.

The window must be show()'n for this function to have any effect. This always calls the system. If you are changing the cursor a lot you may want to keep track of how you set it in a static variable and call this only if the new cursor is different.

The default cursor will be used if the provided image cannot be used as a cursor.

Parameters

image	Sets the cursor size and shape
hotx,hoty	Sets the cursor's active location relatively to top-left of `image` when clicking

See also: cursor(Fl_Cursor), default_cursor()

◆ cursor() [2/3]

void Fl_Window::cursor	(	Fl_Cursor	c,
		Fl_Color	,
		Fl_Color	= `FL_WHITE`
	)

For back compatibility only.

Same as Fl_Window::cursor(Fl_Cursor)

◆ cursor() [3/3]

void Fl_Window::cursor ( Fl_Cursor c )

Changes the cursor for this window.

The window must be show()'n for this function to have any effect. This always calls the system. If you are changing the cursor a lot you may want to keep track of how you set it in a static variable and call this only if the new cursor is different.

The type Fl_Cursor is an enumeration defined in <FL/Enumerations.H>.

See also: cursor(const Fl_RGB_Image*, int, int), default_cursor()

◆ decorated_h()

int Fl_Window::decorated_h ( ) const

Returns the window height including any window title bar and any frame added by the window manager.

Same as h() if applied to a subwindow, or if window is not yet mapped.

Note: Under X11, FLTK is able to compute the size of window titlebars and borders only if these decoration elements are strictly X11-based. When that's not the case, decorated_h() returns the same value as h() and decorated_w() as w(), and FLTK cannot access window decorations.; Under X11 again, the values returned by decorated_h() and decorated_w() may not be reliable during a resize operation. The size of decoration elements of a window is best computed when the window is first mapped.

◆ decorated_w()

int Fl_Window::decorated_w ( ) const

Returns the window width including any frame added by the window manager.

Same as w() if applied to a subwindow, or if window is not yet mapped.

See also: decorated_h().

◆ default_cursor() [1/2]

void Fl_Window::default_cursor	(	Fl_Cursor	c,
		Fl_Color	,
		Fl_Color	= `FL_WHITE`
	)

For back compatibility only.

same as Fl_Window::default_cursor(Fl_Cursor)

◆ default_cursor() [2/2]

void Fl_Window::default_cursor ( Fl_Cursor c )

Sets the default window cursor.

This is the cursor that will be used after the mouse pointer leaves a widget with a custom cursor set.

See also: cursor(const Fl_RGB_Image*, int, int), default_cursor()

◆ default_icon()

void Fl_Window::default_icon ( const Fl_RGB_Image * icon )

static

Sets a single default window icon.

If icon is NULL the current default icons are removed.

Parameters

[in] icon default icon for all windows subsequently created or NULL

See also: Fl_Window::default_icons(const Fl_RGB_Image *[], int); Fl_Window::icon(const Fl_RGB_Image *); Fl_Window::icons(const Fl_RGB_Image *[], int)

Note: See Window icons for the Wayland platform.

◆ default_icons() [1/2]

void Fl_Window::default_icons	(	const Fl_RGB_Image *	icons[],
		int	count
	)

static

Sets the default window icons.

The default icons are used for all windows that don't have their own icons set before show() is called. You can change the default icons whenever you want, but this only affects windows that are created (and shown) after this call.

The given images in icons are copied. You can use a local variable or free the images immediately after this call.

Parameters

[in]	icons	default icons for all windows subsequently created
[in]	count	number of images in `icons`. Set to 0 to remove the current default icons

See also: Fl_Window::default_icon(const Fl_RGB_Image *); Fl_Window::icon(const Fl_RGB_Image *); Fl_Window::icons(const Fl_RGB_Image *[], int)

Note: See Window icons for the Wayland platform.

◆ default_icons() [2/2]

static void Fl_Window::default_icons	(	HICON	big_icon,
		HICON	small_icon
	)

static

Sets the default window icons (Windows platform only).

Convenience function to set the default icons using Windows' native HICON icon handles.

The given icons are copied. You can free the icons immediately after this call.

Parameters

[in]	big_icon	default large icon for all windows subsequently created
[in]	small_icon	default small icon for all windows subsequently created

See also: Fl_Window::default_icon(const Fl_RGB_Image *); Fl_Window::default_icons(const Fl_RGB_Image *[], int); Fl_Window::icon(const Fl_RGB_Image *); Fl_Window::icons(const Fl_RGB_Image *[], int); Fl_Window::icons(HICON, HICON)

◆ default_size_range()

void Fl_Window::default_size_range ( )

protected

Protected method to calculate the default size range of a window.

This method is called internally prior to showing a window to ensure that the window's size range values are calculated if a resizable() widget has been set but size_range() has not been called explicitly.

This method does nothing if size_range() has been called before.

Otherwise FLTK tries to figure out the window's size range from the setting of the window's resizable() widget as follows and roughly in the given order.

If resizable() is NULL (this is the default) then the window cannot be resized and the resize border and max-size control will not be displayed for the window.
If either dimension of resizable() is zero, then the window cannot resize in that direction.
The resizable() widget is clipped to the window area.
The non-resizable portion of the window is calculated as the difference of the window's size and the clipped resizable() widget's size.
If either dimension of the clipped resizable() widget is greater than 100, then 100 is considered its minimum width/height. This allows the resizable widget to shrink below its original size.
Finally the minimum width/height of the window is set to the non-resizable portion plus the width/height of the resizable() widget as calculated above.

In simple words:

It is assumed that the resizable() widget can be indefinitely enlarged and/or shrunk to a minimum width/height of 100 unless it is smaller than that, which is then considered the minimum.
The window's size_range() minimum values are set to the sum of the non-resizable portion of the window and the previously calculated minimum size of the resizable() widget.

Examples:

Fl_Window win(400, 400);
win.resizable(win);
// win.size_range(100, 100, 0, 0);

The minimum size of the resizable is 100, hence the minimum size of the total window is also 100 in both directions.

Fl_Window win(400, 400);
Fl_Box box(20, 20, 360, 360);
win.resizable(box);
// win.size_range(140, 140, 0, 0);

The calculated minimum width and height would be 20 + 100 + 20 in both dimensions.

Fl_Window win(400, 400);
Fl_Box box(200, 0, 500, 300); // note: width 500 too large: clipped
win.resizable(box);
// win.size_range(300, 200, 0, 0);

The width of the resizable is clipped to 200, hence the minimum size of the total window is also 200 (fix) + 100 (min. resizable) in x direction. The minimum value in y direction is 100 (resizable) + 100 (fixed part).

The calculation is based on clipping the resizable widget to the window area to prevent programming errors and the assumption that the resizable widget can be shrunk to 100x100 or its original size, whichever is smaller.

If this is not what you want, please use Fl_Window::size_range() explicitly so you can set any appropriate range.

◆ default_xclass() [1/2]

const char * Fl_Window::default_xclass ( )

static

Returns the default xclass.

See also: Fl_Window::default_xclass(const char *)

◆ default_xclass() [2/2]

void Fl_Window::default_xclass ( const char * xc )

static

Sets the default window xclass.

The default xclass is used for all windows that don't have their own xclass set before show() is called. You can change the default xclass whenever you want, but this only affects windows that are created (and shown) after this call.

The given string xc is copied. You can use a local variable or free the string immediately after this call.

If you don't call this, the default xclass for all windows will be "FLTK". You can reset the default xclass by specifying NULL for xc.

If you call Fl_Window::xclass(const char *) for any window, then this also sets the default xclass, unless it has been set before.

Parameters

[in] xc default xclass for all windows subsequently created

See also: Fl_Window::xclass(const char *)

◆ draw()

void Fl_Window::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 = &scrollbar; // scrollbar is an embedded Fl_Scrollbar

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

Fl_Widget

Fl_Widget is the base class for all widgets in FLTK.

Definition Fl_Widget.H:104

Reimplemented from Fl_Group.

◆ flush()

void Fl_Window::flush ( )

protectedvirtual

Forces the window to be drawn, this window is also made current and calls draw().

Reimplemented in Fl_Double_Window, Fl_Gl_Window, and Fl_Overlay_Window.

◆ force_position() [1/2]

int Fl_Window::force_position ( ) const

inlineprotected

Returns the internal state of the window's FORCE_POSITION flag.

Return values

1	if flag is set
0	otherwise

See also: force_position(int)

◆ force_position() [2/2]

void Fl_Window::force_position ( int force )

inlineprotected

Sets an internal flag that tells FLTK and the window manager to honor position requests.

This is used internally and should not be needed by user code.

Parameters

[in] force 1 to set the FORCE_POSITION flag, 0 to clear it

◆ free_icons()

void Fl_Window::free_icons ( )

protected

Deletes all icons previously attached to the window.

See also: Fl_Window::icons(const Fl_RGB_Image *icons[], int count)

◆ free_position()

void Fl_Window::free_position ( )

inline

Undoes the effect of a previous resize() or show() so that the next time show() is called the window manager is free to position the window.

This is for Forms compatibility only.

Deprecated:: please use force_position(0) instead

◆ fullscreen()

void Fl_Window::fullscreen ( )

Makes the window completely fill one or more screens, without any window manager border visible.

You must use fullscreen_off() to undo this.

Note: On some platforms, this can result in the keyboard being grabbed. The window may also be recreated, meaning hide() and show() will be called.

See also: void Fl_Window::fullscreen_screens()

◆ fullscreen_screens()

void Fl_Window::fullscreen_screens	(	int	top,
		int	bottom,
		int	left,
		int	right
	)

Sets which screens should be used when this window is in fullscreen mode.

The window will be resized to the top of the screen with index top, the bottom of the screen with index bottom, etc.

If this method is never called, or if any argument is < 0, then the window will be resized to fill the screen it is currently on.

See also: void Fl_Window::fullscreen()

◆ handle()

int Fl_Window::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.

One exception to the rule in the previous paragraph is if you really want to override the behavior of the base class. This requires knowledge of the details of the inherited class.

In rare cases you may want to return 1 from your handle() method although you don't really handle the event. The effect would be to filter event processing, for instance if you want to dismiss non-numeric characters (keypresses) in a numeric input widget. You may "ring the bell" or show another visual indication or drop the event silently. In such a case you must not call the handle() method of the base class and tell FLTK that you consumed the event by returning 1 even if you didn't do anything with it.

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.

◆ hide()

void Fl_Window::hide ( )

virtual

Removes the window from the screen.

If the window is already hidden or has not been shown then this does nothing and is harmless.

Reimplemented from Fl_Widget.

◆ hotspot()

void Fl_Window::hotspot	(	int	x,
		int	y,
		int	offscreen = `0`
	)

Positions the window so that the mouse is pointing at the given position, or at the center of the given widget, which may be the window itself.

If the optional offscreen parameter is non-zero, then the window is allowed to extend off the screen (this does not work with some X window managers).

See also: position()

◆ icon() [1/3]

const void * Fl_Window::icon ( ) const

Gets the current icon window target dependent data.

Deprecated:: in 1.3.3

◆ icon() [2/3]

void Fl_Window::icon ( const Fl_RGB_Image * icon )

Sets or resets a single window icon.

A window icon can be changed while the window is shown, but this may be platform and/or window manager dependent. To be sure that the window displays the correct window icon you should always set the icon before the window is shown.

If a window icon has not been set for a particular window, then the default window icon (see links below) or the system default icon will be used.

This method makes an internal copy of the icon pixel buffer, so once set, the Fl_RGB_Image instance can be freed by the caller.

Parameters

[in] icon icon for this window, NULL to reset window icon.

See also: Fl_Window::default_icon(const Fl_RGB_Image *); Fl_Window::default_icons(const Fl_RGB_Image *[], int); Fl_Window::icons(const Fl_RGB_Image *[], int)

Note: See Window icons for the Wayland platform.

◆ icon() [3/3]

void Fl_Window::icon ( const void * ic )

Platform-specific method to set the window icon usable on Windows and X11 only.

See Setting the Icon of a Window for its use under X11, and Setting the Icon of a Window under Windows.

Deprecated:: in 1.3.3 in favor of platform-independent methods Fl_Window::icon(const Fl_RGB_Image *icon) and Fl_Window::icons(const Fl_RGB_Image *icons[], int count).

◆ iconize()

void Fl_Window::iconize ( )

Iconifies the window.

If you call this when shown() is false it will show() it as an icon. If the window is already iconified this does nothing.

Call show() to restore the window.

When a window is iconified/restored (either by these calls or by the user) the handle() method is called with FL_HIDE and FL_SHOW events and visible() is turned on and off.

There is no way to control what is drawn in the icon except with the string passed to Fl_Window::xclass(). You should not rely on window managers displaying the icons.

◆ icons() [1/2]

void Fl_Window::icons	(	const Fl_RGB_Image *	icons[],
		int	count
	)

Sets the window icons.

You may set multiple window icons with different sizes. Dependent on the platform and system settings the best (or the first) icon will be chosen.

The given images in icons are copied. You can use a local variable or free the images immediately after this call.

If count is zero, current icons are removed. If count is greater than zero (must not be negative), then icons[] must contain at least count valid image pointers (not NULL). Otherwise the behavior is undefined.

Parameters

[in]	icons	icons for this window
[in]	count	number of images in `icons`. Set to 0 to remove the current icons

See also: Fl_Window::default_icon(const Fl_RGB_Image *); Fl_Window::default_icons(const Fl_RGB_Image *[], int); Fl_Window::icon(const Fl_RGB_Image *)

Note: See Window icons for the Wayland platform.

◆ icons() [2/2]

void Fl_Window::icons	(	HICON	big_icon,
		HICON	small_icon
	)

Sets the window icons using HICON handles (Windows platform only).

The given icons are copied. You can free the icons immediately after this call.

Parameters

[in]	big_icon	large window icon
[in]	small_icon	small window icon

◆ is_resizable()

int Fl_Window::is_resizable ( )

protected

Protected method to determine whether a window is resizable.

If size_range() has not yet been called this method calculates the default size range values by calling default_size_range().

This method is for internal use only. The returned value is a bit mask and non-zero if the window is resizable in at least one direction.

Returns: non-zero if the window is resizable

Return values

0	the window is not resizable
1	the window is resizable in horizontal direction (w)
2	the window is resizable in vertical direction (h)
3	the window is resizable in both directions (w and h)

See also: default_size_range()

◆ make_current()

void Fl_Window::make_current ( )

Sets things up so that the drawing functions in <FL/fl_draw.H> will go into this window.

This is useful for incremental update of windows, such as in an idle callback, which will make your program behave much better if it draws a slow graphic. Danger: incremental update is very hard to debug and maintain!

This method only works for the Fl_Window and Fl_Gl_Window derived classes.

◆ maximize()

void Fl_Window::maximize ( )

Maximizes a top-level window to its current screen.

This function is effective only with a show()'n, resizable, top-level window. Bordered and borderless windows can be used.

See also: Fl_Window::un_maximize(), Fl_Window::maximize_active()

◆ modal()

unsigned int Fl_Window::modal ( ) const

inline

Returns true if this window is modal.

◆ os_id()

fl_uintptr_t Fl_Window::os_id ( )

Returns a platform-specific identification of a shown window, or 0 if not shown.

Note

This identification may differ from the platform-specific reference of an Fl_Window object used by functions fl_x11_xid(), fl_mac_xid(), fl_x11_find(), and fl_mac_find().

X11 platform: the window's XID.
macOS platform: The window number of the window’s window device.
other platforms: 0.

◆ resize()

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

virtual

Changes the size and position of the window.

If shown() is true, these changes are communicated to the window server (which may refuse that size and cause a further resize). If shown() is false, the size and position are used when show() is called. See Fl_Group for the effect of resizing on the child widgets.

You can also call the Fl_Widget methods size(x,y) and position(w,h), which are inline wrappers for this virtual function.

A top-level window can not force, but merely suggest a position and size to the operating system. The window manager may not be willing or able to display a window at the desired position or with the given dimensions. It is up to the application developer to verify window parameters after the resize request.

Reimplemented from Fl_Group.

◆ screen_num()

void Fl_Window::screen_num ( int screen_num )

Set the number of the screen where to map the window.

Call this and set also the window's desired position before show()'ing the window. This can be necessary when a system has several screens with distinct scaling factor values because the window's x() and y() may not suffice to uniquely identify one screen. To see that, consider a system with two screens where the screen at left is A pixel-wide and has a scale factor of 1 whereas the screen at right has a scale factor of 2. For the sake of simplicity, consider only the X coordinates of windows. FLTK coordinates translate directly to pixel coordinates on the left screen, whereas FLTK coordinates multiplied by 2 correspond to pixel coordinates on the right screen. Consequently, FLTK coordinates between A/2 + 1 and A-1 can map to both screens. Both window coordinates and screen number are necessary to uniquely identify where a window is to be mapped.

◆ set_menu_window()

void Fl_Window::set_menu_window ( )

inline

Marks the window as a menu window.

This is intended for internal use, but it can also be used if you write your own menu handling. However, this is not recommended.

This flag is used for correct "parenting" of windows in communication with the windowing system. Modern X window managers can use different flags to distinguish menu and tooltip windows from normal windows.

This must be called before the window is shown and cannot be changed later.

◆ set_modal()

void Fl_Window::set_modal ( )

inline

A "modal" window, when shown(), will prevent any events from being delivered to other windows in the same program, and will also remain on top of the other windows (if the X window manager supports the "transient for" property).

Several modal windows may be shown at once, in which case only the last one shown gets events. You can see which window (if any) is modal by calling Fl::modal().

◆ set_non_modal()

void Fl_Window::set_non_modal ( )

inline

A "non-modal" window (terminology borrowed from Microsoft Windows) acts like a modal() one in that it remains on top, but it has no effect on event delivery.

There are three states for a window: modal, non-modal, and normal.

◆ set_tooltip_window()

void Fl_Window::set_tooltip_window ( )

inline

Marks the window as a tooltip window.

This is intended for internal use, but it can also be used if you write your own tooltip handling. However, this is not recommended.

This flag is used for correct "parenting" of windows in communication with the windowing system. Modern X window managers can use different flags to distinguish menu and tooltip windows from normal windows.

This must be called before the window is shown and cannot be changed later.

Note: Since Fl_Tooltip_Window is derived from Fl_Menu_Window, this also clears the menu_window() state.

◆ shape() [1/2]

void Fl_Window::shape ( const Fl_Image & img )

Set the window's shape with an Fl_Image.

See also: void shape(const Fl_Image* img)

◆ shape() [2/2]

void Fl_Window::shape ( const Fl_Image * img )

Assigns a non-rectangular shape to the window.

This function gives an arbitrary shape (not just a rectangular region) to an Fl_Window. An Fl_Image of any dimension can be used as mask; it is rescaled to the window's dimension as needed.

The layout and widgets inside are unaware of the mask shape, and most will act as though the window's rectangular bounding box is available to them. It is up to you to make sure they adhere to the bounds of their masking shape.

The img argument can be an Fl_Bitmap, Fl_Pixmap, Fl_RGB_Image or Fl_Shared_Image:

With Fl_Bitmap or Fl_Pixmap, the shaped window covers the image part where bitmap bits equal one, or where the pixmap is not fully transparent.
With an Fl_RGB_Image with an alpha channel (depths 2 or 4), the shaped window covers the image part that is not fully transparent.
With an Fl_RGB_Image of depth 1 (gray-scale) or 3 (RGB), the shaped window covers the non-black image part.
With an Fl_Shared_Image, the shape is determined by rules above applied to the underlying image. The shared image should not have been scaled through Fl_Image::scale().

Platform details:

On the unix/linux platform, the SHAPE extension of the X server is required. This function does control the shape of Fl_Gl_Window instances.
On the Windows platform, this function does nothing with class Fl_Gl_Window.
On the Mac platform, OS version 10.4 or above is required. An 8-bit shape-mask is used when img is an Fl_RGB_Image: with depths 2 or 4, the image alpha channel becomes the shape mask such that areas with alpha = 0 are out of the shaped window; with depths 1 or 3, white and black are in and out of the shaped window, respectively, and other colors give intermediate masking scores. This function does nothing with class Fl_Gl_Window.

The window borders and caption created by the window system are turned off by default. They can be re-enabled by calling Fl_Window::border(1).

A usage example is found at example/shapedwindow.cxx.

Version: 1.3.3

◆ show() [1/2]

void Fl_Window::show ( )

virtual

Puts the window on the screen.

This has the side effect of opening the display, if not done before.

If the window is already shown then it is restored and raised to the top. This is really convenient because your program can call show() at any time, even if the window is already up. It also means that show() serves the purpose of raise() in other toolkits.

Fl_Window::show(int argc, char **argv) is used for top-level windows and allows standard arguments to be parsed from the command-line.

Note: For some obscure reasons Fl_Window::show() resets the current group by calling Fl_Group::current(0). The comments in the code say "get rid of very common user bug: forgot end()". Although this is true it may have unwanted side effects if you show() an unrelated window (maybe for an error message or warning) while building a window or any other group widget.

Todo:: Check if we can remove resetting the current group in a later FLTK version (after 1.3.x). This may break "already broken" programs though if they rely on this "feature".

See also: Fl_Window::show(int argc, char **argv)

Reimplemented from Fl_Widget.

◆ show() [2/2]

void Fl_Window::show	(	int	argc,
		char **	argv
	)

Puts the window on the screen with show() and parses command-line arguments.

This call should be used for top-level windows, at least for the first (main) window. It allows standard arguments to be parsed, as done by Fl::args(int, char **), from the command-line. You can use argc and argv from main(int argc, char **argv) for this call.

This call also sets up some system-specific internal variables, that is, it sets FL_SELECTION_COLOR and calls Fl::background(), Fl::background2(), Fl::foreground() with default or X resources-given values, and calls Fl::scheme(const char *) for the current scheme. On X11, it also calls Fl::dnd_text_ops(int), Fl_Tooltip::enable(int), Fl::visible_focus(int) with X resources-given values.

Parameters

argc	command-line argument count, usually from main()
argv	command-line argument vector, usually from main()

See also: virtual void Fl_Window::show(); Fl::args(int, char **)

◆ show_next_window_iconic() [1/2]

static char Fl_Window::show_next_window_iconic ( )

inlinestatic

Returns the static flag whether the next window should be opened iconified.

Note: This is an internal function, you should not use this in user code.

Please use Fl_Window::iconize() to iconify a window.

◆ show_next_window_iconic() [2/2]

static void Fl_Window::show_next_window_iconic ( char stat )

inlinestatic

Sets a static flag whether the next window should be opened iconified.

Note: This is an internal function, you should not use this in user code.

Please use Fl_Window::iconize() instead.

◆ shown()

int Fl_Window::shown ( )

inline

Returns non-zero if show() has been called (but not hide() ).

You can tell if a window is iconified with (w->shown() && !w->visible()).

◆ size_range()

void Fl_Window::size_range	(	int	minWidth,
		int	minHeight,
		int	maxWidth = `0`,
		int	maxHeight = `0`,
		int	deltaX = `0`,
		int	deltaY = `0`,
		int	aspectRatio = `0`
	)

Sets the allowable range the user can resize this window to.

We recommend to call size_range() if you have a resizable() widget in a main window, and to call it after setting the resizable() and before show()'ing the window for best cross platform compatibility.

If this function is not called, FLTK tries to figure out the range when the window is shown. Please see the protected method default_size_range() for details.

It is undefined what happens if the current window size does not fit in the constraints passed to size_range().

Note: This only works for top-level windows and the exact behavior can be platform specific. To work correctly across all platforms size_range() must be called after setting the resizable() widget of the window and before the window is show()'n.

Calling size_range() after the window has been shown may work on some but not all platforms. If you need to change the size_range() after the window has been shown, then you should consider to hide() and show() the window again, i.e. call hide(), size_range(), and show() in this order.

Typical usage: call

size_range(minWidth, minHeight);

Fl_Window::size_range

void size_range(int minw, int minh, int maxw=0, int maxh=0, int dw=0, int dh=0, int aspect=0)

Sets the allowable range the user can resize this window to.

Definition Fl_Window.cxx:665

after setting the resizable widget and before calling show(). This ensures that the window cannot be resized smaller than the given values by user interaction.

maxWidth and maxHeight might be useful in some special cases but less frequently used.

The other optional parameters deltaX, deltaY, and aspectRatio are not recommended because they may not work on all platforms and may even under X11 not be supported by all Window Managers.

Parameters

[in]	minWidth,minHeight	The smallest the window can be. Either value must be greater than 0.
[in]	maxWidth,maxHeight	The largest the window can be. If either is equal to the minimum then you cannot resize in that direction. If either is zero then FLTK picks a maximum size in that direction such that the window will fill the screen.
[in]	deltaX,deltaY	These are size increments. The window will be constrained to widths of `minWidth + N * deltaX`, where N is any non-negative integer. If these are less or equal to 1 they are ignored (this is always ignored on Windows).
[in]	aspectRatio	A flag that indicates that the window should preserve its aspect ratio. This only works if both the maximum and minimum have the same aspect ratio (ignored on Windows and by many X window managers).

◆ un_maximize()

void Fl_Window::un_maximize ( )

Returns a previously maximized top-level window to its previous size.

See also: Fl_Window::maximize()

◆ wait_for_expose()

void Fl_Window::wait_for_expose ( )

Waits for the window to be displayed after calling show().

Fl_Window::show() is not guaranteed to show and draw the window on all platforms immediately. Instead this is done in the background; particularly on X11 it will take a few messages (client server roundtrips) to display the window. Usually this small delay doesn't matter, but in some cases you may want to have the window instantiated and displayed synchronously.

Currently (as of FLTK 1.3.4) this method has an effect on X11 and Mac OS. On Windows, show() is always synchronous. The effect of show() varies with versions of Mac OS X: early versions have the window appear on the screen when show() returns, later versions don't. If you want to write portable code and need this synchronous show() feature, add win->wait_for_expose() on all platforms, and FLTK will just do the right thing.

This method can be used for displaying splash screens before calling Fl::run() or for having exact control over which window has the focus after calling show().

If the window is not shown(), this method does nothing.

Note: Depending on the platform and window manager wait_for_expose() may not guarantee that the window is fully drawn when it is called. Under X11 it may only make sure that the window is mapped, i.e. the internal (OS dependent) window object was created (and maybe shown on the desktop as an empty frame or something like that). You may need to call Fl::flush() after wait_for_expose() to make sure the window and all its widgets are drawn and thus visible.; FLTK does the best it can do to make sure that all widgets get drawn if you call wait_for_expose() and Fl::flush(). However, dependent on the window manager it can not be guaranteed that this does always happen synchronously. The only guaranteed behavior that all widgets are eventually drawn is if the FLTK event loop is run continuously, for instance with Fl::run().

See also: virtual void Fl_Window::show()

Example code for displaying a window before calling Fl::run()

Fl_Double_Window win = new Fl_Double_Window(...);
 
// do more window initialization here ...
 
win->show();                // show window
win->wait_for_expose();     // wait, until displayed
Fl::flush();                // make sure everything gets drawn
 
// do more initialization work that needs some time here ...
 
Fl::run();                  // start FLTK event loop

Note that the window will not be responsive until the event loop is started with Fl::run().

◆ xclass() [1/2]

const char * Fl_Window::xclass ( ) const

Returns the xclass for this window, or a default.

See also: Fl_Window::default_xclass(const char *); Fl_Window::xclass(const char *)

◆ xclass() [2/2]

void Fl_Window::xclass ( const char * xc )

Sets the xclass for this window.

A string used to tell the system what type of window this is. Mostly this identifies the picture to draw in the icon. This only works if called before calling show().

Under X, this is turned into a XA_WM_CLASS pair by truncating at the first non-alphanumeric character and capitalizing the first character, and the second one if the first is 'x'. Thus "foo" turns into "foo, Foo", and "xprog.1" turns into "xprog, XProg".

Under Microsoft Windows, this string is used as the name of the WNDCLASS structure, though it is not clear if this can have any visible effect.

Since: FLTK 1.3 the passed string is copied. You can use a local variable or free the string immediately after this call. Note that FLTK 1.1 stores the pointer without copying the string.

If the default xclass has not yet been set, this also sets the default xclass for all windows created subsequently.

See also: Fl_Window::default_xclass(const char *)

Member Data Documentation

◆ current_

Fl_Window * Fl_Window::current_

staticprotected

Stores the last window that was made current.

See current() const

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

Fl_Window.H
Fl_arg.cxx
fl_cursor.cxx
Fl_Window.cxx
Fl_Window_fullscreen.cxx
Fl_Window_hotspot.cxx
Fl_Window_iconize.cxx

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Fl_Window() [1/2]

◆ Fl_Window() [2/2]

◆ ~Fl_Window()

Member Function Documentation

◆ as_double_window()

◆ as_overlay_window()

◆ as_window() [1/2]

◆ as_window() [2/2]

◆ border()

◆ clear_border()

◆ clear_modal_states()

◆ current()

◆ cursor() [1/3]

◆ cursor() [2/3]

◆ cursor() [3/3]

◆ decorated_h()

◆ decorated_w()

◆ default_cursor() [1/2]

◆ default_cursor() [2/2]

◆ default_icon()

◆ default_icons() [1/2]

◆ default_icons() [2/2]

◆ default_size_range()

◆ default_xclass() [1/2]

◆ default_xclass() [2/2]

◆ draw()

◆ flush()

◆ force_position() [1/2]

◆ force_position() [2/2]

◆ free_icons()

◆ free_position()

◆ fullscreen()

◆ fullscreen_screens()

◆ handle()

◆ hide()

◆ hotspot()

◆ icon() [1/3]

◆ icon() [2/3]

◆ icon() [3/3]

◆ iconize()

◆ icons() [1/2]

◆ icons() [2/2]

◆ is_resizable()

◆ make_current()

◆ maximize()

◆ modal()

◆ os_id()

◆ resize()

◆ screen_num()

◆ set_menu_window()

◆ set_modal()

◆ set_non_modal()

◆ set_tooltip_window()

◆ shape() [1/2]

◆ shape() [2/2]

◆ show() [1/2]

◆ show() [2/2]

◆ show_next_window_iconic() [1/2]

◆ show_next_window_iconic() [2/2]

◆ shown()

◆ size_range()

◆ un_maximize()

◆ wait_for_expose()

◆ xclass() [1/2]

◆ xclass() [2/2]

Member Data Documentation

◆ current_