tbq::SettingsIni Class Reference

Class used to manage INI configuration file. More...

Public Types
using	CbHook = std::function<bool(const QFileInfo &fileInfo)>
	Custom callback hook use to implement custom behaviour.

Public Member Functions
bool	loadSettings (const QFileInfo &fileInfo)
	Load settings from INI configuration file.
QFileInfo	getPath () const
void	groupBegin (TOOLBOXQT_QTCOMPAT_STR_VIEW keyGroup)
void	groupEnd ()
void	setValue (TOOLBOXQT_QTCOMPAT_STR_VIEW key, const QVariant &value)
QVariant	getValue (TOOLBOXQT_QTCOMPAT_STR_VIEW key, const QVariant &defaultValue=QVariant()) const
	Use to retrieve value from .ini file.
QString	getString (TOOLBOXQT_QTCOMPAT_STR_VIEW key, const QString &defaultValue=QString()) const
	Use to retrieve a string from .ini file.
void	setHooksPreLoadSettings (CbHook hookPreload)
	Use to set custom behaviour before loading settings.
void	setHooksPostLoadSettings (CbHook hookPostload)
	Use to set custom behaviour after loading settings.

Detailed Description

Class used to manage INI configuration file.

This class allow to easily manage settings depending on a .ini file.
It will allow for example to not have to remember path of configuration file each time we need it !

Note

Don't use this class if INI format is not mandatory, QSettings already provide a way to manage other format without settings parameters each time at: https://doc.qt.io/qt-6/qsettings.html#basic-usage

To use this class in a project, it will be easier to create a singleton from it adpated to our specific configuration file.
This class also allow to have a custom behaviour for pre and post load operations of the configuration file via setHooksPreLoadSettings() and setHooksPostLoadSettings().
We can defines custom ones like this:

• Header file:

  #ifndef PREFERENCES_H
  #define PREFERENCES_H
   
  #include "toolboxqt/core/settingsini.h"
   
  #include <QVersionNumber>
   
  #define mPrefs  (Preferences::instance())
   
  class Preferences final : public QObject
  {
      Q_OBJECT
      APP_DISABLE_COPY_MOVE(Preferences)
   
  public:
      static Preferences& instance();
   
  public:
      void setup(const QFileInfo &fileInfo);
   
  private:
      Preferences();
   
  private:
      bool preLoadSettings(const QFileInfo &fileInfo);
      bool postLoadSettings(const QFileInfo &fileInfo);
   
  private:
      tbq::SettingsIni m_settings;
   
  private:
      static const QVersionNumber SUPPORT_VERSION;
  };
   
  #endif // PREFERENCES_H

• Source file:

  #include "preferences.h"
   
  #include "toolboxqt/core/corehelper.h"
   
  const QVersionNumber Preferences::SUPPORT_VERSION = QVersionNumber(1, 0, 0);
   
  Preferences& Preferences::instance()
  {
      static Preferences instance;
      return instance;
  }
   
  Preferences::Preferences()
  {
      /* Nothing to do */
  }
   
  void Preferences::setup(const QFileInfo &fileInfo)
  {
      // Here we use "std::bind", but we could have also used a lambda function instead
      m_settings.setHooksPreLoadSettings(std::bind(&Preferences::preLoadSettings, this, std::placeholders::_1));
      m_settings.setHooksPostLoadSettings(std::bind(&Preferences::postLoadSettings, this, std::placeholders::_1));
   
      m_settings.loadSettings(fileInfo);
  }
   
  bool Preferences::preLoadSettings(const QFileInfo &fileInfo)
  {
      /* Verify that configuration file exists */
      const QString filePath = fileInfo.absoluteFilePath();
      if(!QFile::exists(filePath)){
          const QString err = QString("Could not find configuration file: %1").arg(filePath);
          tbq::CoreHelper::quitApplication(err);
          return false;
      }
   
      return true;
  }
   
  bool Preferences::postLoadSettings(APP_VAR_UNUSED const QFileInfo &fileInfo)
  {
      static const QString KEY_VERSION_FILE = "app/version_cfg_file";
   
      /* Verify configuration version compatibility */
      const QString semverStr = m_settings.getValue(KEY_VERSION_FILE).toString();
      const QVersionNumber semver = QVersionNumber::fromString(semverStr);
   
      if(semver.majorVersion() < SUPPORT_VERSION.majorVersion() || semver.majorVersion() > SUPPORT_VERSION.majorVersion()){
          QString err = QString("Unable to load configuration file of application, version is unsupported [read: %1, major-supported: %2]")
          .arg(semver.toString()).arg(SUPPORT_VERSION.majorVersion());
   
          tbq::CoreHelper::quitApplication(err);
          return false;
      }
   
      /* Update file settings properties */
      m_settings.setValue(KEY_VERSION_FILE, SUPPORT_VERSION.toString());
   
      return true;
  }

Then we only have to initialize it in our main:

#include "mainwindow.h"
 
#include <QApplication>
 
#include "preferences.h"
 
/*****************************/
/* Macro definitions         */
/*****************************/
#define APP_CFG_FILE    "configurations/configuration.ini"
 
/*****************************/
/* Main method               */
/*****************************/
int main(int argc, char *argv[])
{
    /* Manage application properties */
    QApplication app(argc, argv);
 
    /* Set application configuration file */
    Preferences::instance().setup(QFileInfo(APP_CFG_FILE));
 
    /* Create main window */
    MainWindow mainWindow;
    mainWindow.show();
 
    return app.exec();
}

Then we can use it anywhere with:

mPrefs.getValue("mySection/myKey");

Member Typedef Documentation

CbHook

using tbq::SettingsIni::CbHook = std::function<bool(const QFileInfo &fileInfo)>

Custom callback hook use to implement custom behaviour.

Parameters

[in]

fileInfo

Path to configuration file used with loadSettings()

Note

Defining custom hook is not mandatory, default are provided (they do nothing excepting returning true).

Returns

Must return true if succeed.

See also

setHooksPreLoadSettings(), setHooksPostLoadSettings()

Member Function Documentation

loadSettings()

bool tbq::SettingsIni::loadSettings

(

const QFileInfo &

fileInfo

)

Load settings from INI configuration file.

Parameters

fileInfo

INI configuration file to use

Returns

Return true if loading succeed.

See also

setHooksPreLoadSettings(), setHooksPostLoadSettings()

getValue()

QVariant tbq::SettingsIni::getValue	(	TOOLBOXQT_QTCOMPAT_STR_VIEW	key,
		const QVariant &	defaultValue = QVariant() ) const

Use to retrieve value from .ini file.

Parameters

[in]	key	Key of parameter to retrieve at format section/my_field.
[in]	defaultValue	Value to use if the setting key doesn't exist

Returns

Returns value associated to key or defaultValue if field doesn't exists.

See also

getString()

setValue()

getString()

QString tbq::SettingsIni::getString	(	TOOLBOXQT_QTCOMPAT_STR_VIEW	key,
		const QString &	defaultValue = QString() ) const

Use to retrieve a string from .ini file.

This method differs from getValue() because here, default value will also be returned if the field exist but the value is empty.

Parameters

[in]	key	Key of parameter to retrieve at format section/my_field.
[in]	defaultValue	Value to use if: The setting key doesn't exist Retrieved string value is empty

Returns

Returns value associated to key or defaultValue

See also

getValue()

setValue()

setHooksPreLoadSettings()

void tbq::SettingsIni::setHooksPreLoadSettings

(

CbHook

hookPreload

)

Use to set custom behaviour before loading settings.

Parameters

hookPreload

Custom callback to use

See also

setHooksPostLoadSettings()

setHooksPostLoadSettings()

void tbq::SettingsIni::setHooksPostLoadSettings

(

CbHook

hookPostload

)

Use to set custom behaviour after loading settings.

Parameters

hookPostload

Custom callback to use

See also

setHooksPreLoadSettings()

---

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

• include/toolboxqt/core/settingsini.h
• src/core/settingsini.cpp