v1::preferences Class Reference

#include <hikogui/settings/preferences.hpp>

Public Member Functions
	preferences () noexcept
	Construct a preferences instance.
	preferences (std::filesystem::path location) noexcept
	Construct a preferences instance.
	preferences (std::string_view location)
	preferences (std::string const &location)
	preferences (char const *location)
	preferences (preferences const &)=delete
	preferences (preferences &&)=delete
preferences &	operator= (preferences const &)=delete
preferences &	operator= (preferences &&)=delete
void	save () const noexcept
	Save the preferences.
void	save (std::filesystem::path location) noexcept
	Save the preferences.
void	load () noexcept
	Load the preferences.
void	load (std::filesystem::path location) noexcept
	Load the preferences.
void	reset () noexcept
	Reset data members to their default value.
template<typename T >
void	add (std::string_view path, observer< T > const &item, T init=T{}) noexcept
	Register an observer to a preferences file.

Data Fields
std::mutex	mutex
	Mutex used to synchronize changes to the preferences.

Friends
class	detail::preference_item_base
template<typename T >
class	detail::preference_item

Detailed Description

user preferences.

A preferences objects maintains a link between observer in the application and a preferences file.

When loading preferences the observer are set to the value in the preferences file. When an observer changes a value the preferences file is updated to reflect this change. For performance reasons multiple modifications are combined into a single save.

An application may open multiple preferences files, for example an application preferences file and a project-specific preferences file. The name of the project-specific preferences file can then be selected by the user.

The preferences file is updated by using the operating system specific call to overwrite an existing file atomically.

Constructor & Destructor Documentation

preferences() [1/2]

v1::preferences::preferences ( )

inlinenoexcept

Construct a preferences instance.

No current preferences file will be selected.

It is recommended to call preferences::load(std::filesystem::path) after the constructor.

preferences() [2/2]

v1::preferences::preferences ( std::filesystem::path location )

inlinenoexcept

Construct a preferences instance.

The current preferences file is changed to the location give.

Parameters

location

The location of the preferences file to load from.

Member Function Documentation

add()

template<typename T >

void v1::preferences::add ( std::string_view path, observer< T > const & item, T init = T{} )

inlinenoexcept

Register an observer to a preferences file.

Parameters

path	The json-path inside the preference file.
item	The observer to monitor.
init	The value of the observer when it is not present in the preferences file.

load() [1/2]

void v1::preferences::load ( )

inlinenoexcept

Load the preferences.

This will load the preferences from the current selected file.

load() [2/2]

void v1::preferences::load ( std::filesystem::path location )

inlinenoexcept

Load the preferences.

This will change the current preferences file to the location given.

Parameters

location

The file to save the preferences to.

reset()

void v1::preferences::reset ( )

inlinenoexcept

Reset data members to their default value.

save() [1/2]

void v1::preferences::save ( ) const

inlinenoexcept

Save the preferences.

This will load the preferences from the current selected file.

save() [2/2]

void v1::preferences::save ( std::filesystem::path location )

inlinenoexcept

Save the preferences.

This will change the current preferences file to the location given.

Parameters

location

The file to save the preferences to.

Field Documentation

mutex

std::mutex v1::preferences::mutex

mutable

Mutex used to synchronize changes to the preferences.

This mutex may be used externally to atomically combine multiple observer modification into a single change of the preferences file.

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

• hikogui/src/hikogui/settings/preferences.hpp