StyleOptions Class Reference

#include <Pt/Forms/StyleOptions.h>

Stores named appearance options. More...

Public Member Functions
	StyleOptions ()
	Constructs an empty options object.
	StyleOptions (const StyleOptions &o)
	Copies o.
	~StyleOptions ()
	Destructor.
StyleOptions &	operator= (const StyleOptions &o)
	Assigns o.
std::size_t	generation () const
	Returns the current change generation.
bool	hasOptions () const
	Returns true if this object contains any local option.
bool	isDefault (const StyleOptions &base) const
	Returns true if this object does not override base.
void	bind (const StyleOptions *inherited)
	Binds this overlay to the parent options inherited.
const StyleOptions *	parent () const
	Returns the bound parent options, or 0.
template<typename T>
const T *	findLocal () const
	Returns the local option of type T, or 0.
template<typename T>
const T *	find () const
	Returns the local or inherited option of type T, or 0.
template<typename T>
const T &	get () const
	Returns the local or inherited option of type T.
template<typename T>
void	set (const T &option)
	Adds or replaces the local option of type T.
template<typename T>
void	reset ()
	Removes the local option of type T if present.

Static Public Member Functions
static StyleOptions	defaults ()
	Returns options filled with the built-in default values.

Static Public Attributes
static const std::size_t	InvalidGeneration = 0
	Invalid generation value.

Detailed Description

A StyleOptions object contains named appearance options, such as the application background, text colors, accent color, contour pen, and default font. A Style uses these values when it prepares the renderers that paint controls.

Application owns the global style options. It creates them from defaults() and uses them with the default PlatinumStyle. To change the application theme, create an options object, change the values that the application requires, and pass it to Application::setStyleOptions(). The application resets its renderers and invalidates its widgets so that the new appearance is applied.

Pt::Forms::StyleOptions options = Pt::Forms::StyleOptions::defaults();
 
options.set(
    Pt::Forms::AccentColorOption(Pt::Gfx::Color(20, 140, 250))
);
options.set(
    Pt::Forms::TextColorOption(Pt::Gfx::Color(30, 30, 30))
);
 
Pt::Forms::Application& app = Pt::Forms::Application::instance();
app.setStyleOptions(options);

The default constructor creates an empty options object. An empty object is useful as a local overlay for a control. A styler binds this overlay to the application options. A local option overrides the option of the same type in the application options, while an option that is not present locally continues to use the application value. Application owns the live global instance, constructed from defaults(). Application::styleOptions() returns that object as const.

findLocal() searches only this object and returns 0 when the option is not stored locally. find() searches this object and then its bound parent. After bind(), get() returns a local or inherited token and throws std::logic_error when the requested option is not available. set() adds or replaces a local option, and reset() removes a local option.

StyleOptions stores tokens that every style can honor. Look-specific metrics stay in the derived style or renderer.

FontOption supports complete and partial font overrides. A local option can change only the font size, weight, or slant while inheriting the font family and all remaining attributes from the application font.

generation() changes when local options or their binding change. Stylers use the generation to detect that a renderer must prepare its drawing state again.

Member Function Documentation

generation()

std::size_t generation

(

)

const

The generation changes when local options or their binding change.

bind()

void bind

(

const StyleOptions *

inherited

)

Rebinding with the same parent and parent generation does no work. Passing 0 removes the parent.

get()

template<typename T>

const T & get

(

)

const

Exceptions

%std::logic_error

if the requested option is not available.