Gtk::Adjustment Class Reference

A class representing an adjustable bounded value. More...

Collaboration diagram for Gtk::Adjustment:

Public Member Functions
virtual	~Adjustment ()
GtkAdjustment*	gobj ()
	Provides access to the underlying C GtkObject.
const GtkAdjustment*	gobj () const
	Provides access to the underlying C GtkObject.
	Adjustment (double value, double lower, double upper, double step_increment=1, double page_increment=10, double page_size=0)
	Constructor to create an Adjustment object.
void	changed ()
	Emits a "changed" signal from the Adjustment.
void	value_changed ()
	Emits a "value_changed" signal from the Adjustment.
void	clamp_page (double lower, double upper)
	Updates the Adjustment value to ensure that the range between the parameters lower and upper is in the current page (i.e. between value and value + page_size).
void	set_value (double value)
	Sets the current value of the Adjustment.
double	get_value () const
	Gets the current value of the adjustment.
void	set_lower (double lower)
	Sets the minimum value of the adjustment.
double	get_lower () const
	Retrieves the minimum value of the adjustment.
void	set_upper (double upper)
	Sets the maximum value of the adjustment.
double	get_upper () const
	Retrieves the maximum value of the adjustment.
void	set_step_increment (double step_increment)
	Sets the step increment of the adjustment.
double	get_step_increment () const
	Retrieves the step increment of the adjustment.
void	set_page_increment (double page_increment)
	Sets the page increment of the adjustment.
double	get_page_increment () const
	Retrieves the page increment of the adjustment.
void	set_page_size (double page_size)
	Sets the page size of the adjustment.
double	get_page_size () const
	Retrieves the page size of the adjustment.
void	configure (double value, double lower, double upper, double step_increment, double page_increment, double page_size)
	Sets all properties of the adjustment at once.
Glib::SignalProxy0< void >	signal_changed ()
Glib::SignalProxy0< void >	signal_value_changed ()
Protected Member Functions
virtual void	on_changed ()
virtual void	on_value_changed ()
Related Functions
(Note that these are not member functions.)
Gtk::Adjustment*	wrap (GtkAdjustment* object, bool take_copy=false)
	A Glib::wrap() method for this object.

Detailed Description

A class representing an adjustable bounded value.

The Gtk::Adjustment object represents a value which has an associated lower and upper bound, together with step and page increments, and a page size. It is used within several gtkmm widgets, including Gtk::SpinButton, Gtk::Viewport, and Gtk::Range (which is a base class for Gtk::HScrollbar, Gtk::VScrollbar, Gtk::HScale, and Gtk::VScale).

The Gtk::Adjustment object does not update the value itself. Instead it is left up to the owner of the Gtk::Adjustment to control the value.

The owner of the Gtk::Adjustment typically calls the value_changed() and changed() functions after changing the value and its bounds. This results in the emission of the "value_changed" or "changed" signal respectively.

Constructor & Destructor Documentation

virtual Gtk::Adjustment::~Adjustment ( ) [virtual]

Gtk::Adjustment::Adjustment	(	double	value,
		double	lower,
		double	upper,
		double	step_increment = `1`,
		double	page_increment = `10`,
		double	page_size = `0`
	)

Constructor to create an Adjustment object.

Parameters:

	value	The initial value
	lower	The minimum value
	upper	The maximum value
	step_increment	The step increment
	page_increment	The page increment
	page_size	The page size

Member Function Documentation

void Gtk::Adjustment::changed ( )

Emits a "changed" signal from the Adjustment.

This is typically called by the owner of the Adjustment after it has changed any of the Adjustment fields other than the value.

void Gtk::Adjustment::clamp_page	(	double	lower,
		double	upper
	)

Updates the Adjustment value to ensure that the range between the parameters lower and upper is in the current page (i.e. between value and value + page_size).

If this range is larger than the page size, then only the start of it will be in the current page. A "changed" signal will be emitted if the value is changed.

Parameters:

	upper	The upper value.
	lower	The lower value.

void Gtk::Adjustment::configure	(	double	value,
		double	lower,
		double	upper,
		double	step_increment,
		double	page_increment,
		double	page_size
	)

Sets all properties of the adjustment at once.

Use this function to avoid multiple emissions of the "changed" signal. See set_lower() for an alternative way of compressing multiple emissions of "changed" into one.

Since gtkmm 2.14:

Parameters:

	value	The new value.
	lower	The new minimum value.
	upper	The new maximum value.
	step_increment	The new step increment.
	page_increment	The new page increment.
	page_size	The new page size.

double Gtk::Adjustment::get_lower ( ) const

Retrieves the minimum value of the adjustment.

Since gtkmm 2.14:

Returns:: The current minimum value of the adjustment.

double Gtk::Adjustment::get_page_increment ( ) const

Retrieves the page increment of the adjustment.

Since gtkmm 2.14:

Returns:: The current page increment of the adjustment.

double Gtk::Adjustment::get_page_size ( ) const

Retrieves the page size of the adjustment.

Since gtkmm 2.14:

Returns:: The current page size of the adjustment.

double Gtk::Adjustment::get_step_increment ( ) const

Retrieves the step increment of the adjustment.

Since gtkmm 2.14:

Returns:: The current step increment of the adjustment.

double Gtk::Adjustment::get_upper ( ) const

Retrieves the maximum value of the adjustment.

Since gtkmm 2.14:

Returns:: The current maximum value of the adjustment.

double Gtk::Adjustment::get_value ( ) const

Gets the current value of the adjustment.

See set_value().

Returns:: The current value of the adjustment.

const GtkAdjustment* Gtk::Adjustment::gobj ( ) const [inline]

Provides access to the underlying C GtkObject.

Reimplemented from Gtk::Object.

GtkAdjustment* Gtk::Adjustment::gobj ( ) [inline]

Provides access to the underlying C GtkObject.

Reimplemented from Gtk::Object.

virtual void Gtk::Adjustment::on_changed ( ) [protected, virtual]

virtual void Gtk::Adjustment::on_value_changed ( ) [protected, virtual]

void Gtk::Adjustment::set_lower ( double lower )

Sets the minimum value of the adjustment.

When setting multiple adjustment properties via their individual setters, multiple "changed" signals will be emitted. However, since the emission of the "changed" signal is tied to the emission of the "GObject::notify" signals of the changed properties, it's possible to compress the "changed" signals into one by calling Glib::object_freeze_notify() and Glib::object_thaw_notify() around the calls to the individual setters.

Alternatively, using a single Glib::object_set() for all the properties to change, or using configure() has the same effect of compressing "changed" emissions.

Since gtkmm 2.14:

Parameters:

lower

The new minimum value.

void Gtk::Adjustment::set_page_increment ( double page_increment )

Sets the page increment of the adjustment.

See set_lower() about how to compress multiple emissions of the "changed" signal when setting multiple adjustment properties.

Since gtkmm 2.14:

Parameters:

page_increment

The new page increment.

void Gtk::Adjustment::set_page_size ( double page_size )

Sets the page size of the adjustment.

See set_lower() about how to compress multiple emissions of the "changed" signal when setting multiple adjustment properties.

Since gtkmm 2.14:

Parameters:

page_size

The new page size.

void Gtk::Adjustment::set_step_increment ( double step_increment )

Sets the step increment of the adjustment.

See set_lower() about how to compress multiple emissions of the "changed" signal when setting multiple adjustment properties.

Since gtkmm 2.14:

Parameters:

step_increment

The new step increment.

void Gtk::Adjustment::set_upper ( double upper )

Sets the maximum value of the adjustment.

Note that values will be restricted by <literal>upper - page-size</literal> if the page-size property is nonzero.

See set_lower() about how to compress multiple emissions of the "changed" signal when setting multiple adjustment properties.

Since gtkmm 2.14:

Parameters:

upper

The new maximum value.

void Gtk::Adjustment::set_value ( double value )

Sets the current value of the Adjustment.

Parameters:

value

The new value of the Adjustment.

Glib::SignalProxy0< void > Gtk::Adjustment::signal_changed ( )

Prototype:: void on_my_changed()

Glib::SignalProxy0< void > Gtk::Adjustment::signal_value_changed ( )

Prototype:: void on_my_value_changed()

void Gtk::Adjustment::value_changed ( )

Emits a "value_changed" signal from the Adjustment.

This is typically called by the owner of the Adjustment after it has changed the Adjustment value field.

Friends And Related Function Documentation

Gtk::Adjustment* wrap	(	GtkAdjustment *	object,
		bool	take_copy = `false`
	)			`[related]`

A Glib::wrap() method for this object.

Parameters:

	object	The C instance.
	take_copy	False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns:: A C++ instance that wraps this C instance.

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

gtkmm/adjustment.h

Gtk::Adjustment Class Reference

Public Member Functions

Protected Member Functions

Related Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation