\inmodule QtCore More...

#include <qtranslator.h>

Inheritance diagram for QTranslator:

Collaboration diagram for QTranslator:

Public Member Functions
	QTranslator (QObject *parent=nullptr)
	Constructs an empty message file object with parent parent that is not connected to any file.

	~QTranslator ()
	Destroys the object and frees any allocated resources.

virtual QString	translate (const char context, const char sourceText, const char *disambiguation=nullptr, int n=-1) const
	Returns the translation for the key (context, sourceText, disambiguation).

virtual bool	isEmpty () const
	Returns `true` if this translator is empty, otherwise returns `false`.

QString	language () const

QString	filePath () const

bool	load (const QString &filename, const QString &directory=QString(), const QString &search_delimiters=QString(), const QString &suffix=QString())
	Loads filename + suffix (".qm" if the suffix is not specified), which may be an absolute file name or relative to directory.

bool	load (const QLocale &locale, const QString &filename, const QString &prefix=QString(), const QString &directory=QString(), const QString &suffix=QString())

bool	load (const uchar *data, int len, const QString &directory=QString())

Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)
	Constructs an object with parent object parent.

virtual	~QObject ()
	Destroys the object, deleting all its child objects.

virtual bool	event (QEvent *event)
	This virtual function receives events to an object and should return true if the event e was recognized and processed.

virtual bool	eventFilter (QObject watched, QEvent event)
	Filters events if this object has been installed as an event filter for the watched object.

QString	objectName () const

Q_WEAK_OVERLOAD void	setObjectName (const QString &name)
	Sets the object's name to name.

void	setObjectName (QAnyStringView name)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

QBindable< QString >	bindableObjectName ()

bool	isWidgetType () const
	Returns `true` if the object is a widget; otherwise returns `false`.

bool	isWindowType () const
	Returns `true` if the object is a window; otherwise returns `false`.

bool	isQuickItemType () const
	Returns `true` if the object is a QQuickItem; otherwise returns `false`.

bool	signalsBlocked () const noexcept
	Returns `true` if signals are blocked; otherwise returns `false`.

bool	blockSignals (bool b) noexcept
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it).

QThread *	thread () const
	Returns the thread in which the object lives.

void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children.

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
	This is an overloaded function that will start a timer of type timerType and a timeout of interval milliseconds.

int	startTimer (std::chrono::milliseconds time, Qt::TimerType timerType=Qt::CoarseTimer)

void	killTimer (int id)
	Kills the timer with timer identifier, id.

template<typename T >
T	findChild (const QString &aName=QString(), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns the child of this object that can be cast into type T and that is called name, or \nullptr if there is no such object.

template<typename T >
QList< T >	findChildren (const QString &aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects.

template<typename T >
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

const QObjectList &	children () const
	Returns a list of child objects.

void	setParent (QObject *parent)
	Makes the object a child of parent.

void	installEventFilter (QObject *filterObj)
	Installs an event filter filterObj on this object.

void	removeEventFilter (QObject *obj)
	Removes an event filter object obj from this object.

QMetaObject::Connection	connect (const QObject sender, const char signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const

bool	disconnect (const char signal=nullptr, const QObject receiver=nullptr, const char *member=nullptr) const

bool	disconnect (const QObject receiver, const char member=nullptr) const

void	dumpObjectTree () const
	Dumps a tree of children to the debug output.

void	dumpObjectInfo () const
	Dumps information about signal connections, etc.

bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value.

bool	setProperty (const char *name, QVariant &&value)

QVariant	property (const char *name) const
	Returns the value of the object's name property.

QList< QByteArray >	dynamicPropertyNames () const

QBindingStorage *	bindingStorage ()

const QBindingStorage *	bindingStorage () const

QObject *	parent () const
	Returns a pointer to the parent object.

bool	inherits (const char *classname) const
	Returns `true` if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns `false`.

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe

Signals inherited from QObject
void	destroyed (QObject *=nullptr)
	This signal is emitted immediately before the object obj is destroyed, after any instances of QPointer have been notified, and cannot be blocked.

void	objectNameChanged (const QString &objectName, QPrivateSignal)
	This signal is emitted after the object's name has been changed.

Static Public Member Functions inherited from QObject
static QMetaObject::Connection	connect (const QObject sender, const char signal, const QObject receiver, const char member, Qt::ConnectionType=Qt::AutoConnection)
	\threadsafe

static QMetaObject::Connection	connect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::ContextTypeForFunctor< Func2 >::ContextType context, Func2 &&slot, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 &&slot)

static bool	disconnect (const QObject sender, const char signal, const QObject receiver, const char member)
	\threadsafe

static bool	disconnect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &member)

static bool	disconnect (const QMetaObject::Connection &)
	Disconnect a connection.

template<typename Func1 , typename Func2 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::FunctionPointer< Func2 >::Object receiver, Func2 slot)

template<typename Func1 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const QObject receiver, void **zero)

Protected Member Functions inherited from QObject
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns \nullptr.

int	senderSignalIndex () const

int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal.

bool	isSignalConnected (const QMetaMethod &signal) const

virtual void	timerEvent (QTimerEvent *event)
	This event handler can be reimplemented in a subclass to receive timer events for the object.

virtual void	childEvent (QChildEvent *event)
	This event handler can be reimplemented in a subclass to receive child events.

virtual void	customEvent (QEvent *event)
	This event handler can be reimplemented in a subclass to receive custom events.

virtual void	connectNotify (const QMetaMethod &signal)

virtual void	disconnectNotify (const QMetaMethod &signal)

	QObject (QObjectPrivate &dd, QObject *parent=nullptr)

Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr

Properties inherited from QObject
QString	objectName
	the name of this object

Related Symbols inherited from QObject
template< class T > T	qobject_cast (const QObject *object)
	Returns the given object cast to type T if the object is of type T (or of a subclass); otherwise returns \nullptr.

template< typename T > T	qFindChildqFindChildren (const QObject *obj, const QString &name)()

template< typename T > QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()

	QObjectList
	\macro Q_CLASSINFO(Name, Value)

Detailed Description

\inmodule QtCore

The QTranslator class provides internationalization support for text output.

An object of this class contains a set of translations from a source language to a target language. QTranslator provides functions to look up translations in a translation file. Translation files are created using \l{Qt Linguist}.

The most common use of QTranslator is to: load a translation file, and install it using QCoreApplication::installTranslator().

Here's an example main() function using the QTranslator:

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
    QTranslator translator;
    // look up e.g. :/i18n/myapp_de.qm
    if (translator.load(QLocale(), "myapp"_L1, "_"_L1, ":/i18n"_L1))
        QCoreApplication::installTranslator(&translator);
 
    QPushButton hello(QCoreApplication::translate("main", "Hello world!"));
    hello.resize(100, 30);
 
    hello.show();
    return app.exec();
}

Note that the translator must be created before the application's widgets.

Most applications will never need to do anything else with this class. The other functions provided by this class are useful for applications that work on translator files.

Definition at line 18 of file qtranslator.h.

Constructor & Destructor Documentation

◆ QTranslator()

QTranslator::QTranslator ( QObject * parent = nullptr )

explicit

Constructs an empty message file object with parent parent that is not connected to any file.

Definition at line 380 of file qtranslator.cpp.

◆ ~QTranslator()

QTranslator::~QTranslator ( )

Destroys the object and frees any allocated resources.

Definition at line 389 of file qtranslator.cpp.

References d, QCoreApplication::instance(), and QCoreApplication::removeTranslator().

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Member Function Documentation

◆ filePath()

QString QTranslator::filePath ( ) const

Since: 5.15

Returns the path of the loaded translation file.

The file path is empty if no translation was loaded yet, the loading failed, or if the translation was not loaded from a file.

Definition at line 1120 of file qtranslator.cpp.

References d.

◆ isEmpty()

bool QTranslator::isEmpty ( ) const

virtual

Returns true if this translator is empty, otherwise returns false.

This function works with stripped and unstripped translation files.

Reimplemented in ProxyTranslator.

Definition at line 1093 of file qtranslator.cpp.

References d.

Referenced by QCoreApplication::installTranslator().

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◆ language()

QString QTranslator::language ( ) const

Since: 5.15

Returns the target language as stored in the translation file.

Definition at line 1105 of file qtranslator.cpp.

References d.

◆ load() [1/3]

bool QTranslator::load	(	const QLocale &	locale,
		const QString &	filename,
		const QString &	prefix = `QString()`,
		const QString &	directory = `QString()`,
		const QString &	suffix = `QString()`
	)

Since: 4.8

Loads filename + prefix + \l{QLocale::uiLanguages()}{ui language name} + suffix (".qm" if the suffix is not specified), which may be an absolute file name or relative to directory. Returns true if the translation is successfully loaded; otherwise returns false.

The previous contents of this translator object are discarded.

If the file name does not exist, other file names are tried in the following order:

\list 1

File name without suffix appended.
File name with ui language part after a "_" character stripped and suffix.
File name with ui language part stripped without suffix appended.
File name with ui language part stripped further, etc. \endlist

For example, an application running in the locale with the following \l{QLocale::uiLanguages()}{ui languages} - "es", "fr-CA", "de" might call load(QLocale(), "foo", ".", "/opt/foolib", ".qm"). load() would replace '-' (dash) with '_' (underscore) in the ui language and then try to open the first existing readable file from this list:

\list 1

/opt/foolib/foo.es.qm
/opt/foolib/foo.es
/opt/foolib/foo.fr_CA.qm
/opt/foolib/foo.fr_CA
/opt/foolib/foo.fr.qm
/opt/foolib/foo.fr
/opt/foolib/foo.de.qm
/opt/foolib/foo.de
/opt/foolib/foo.qm
/opt/foolib/foo.
/opt/foolib/foo \endlist

On operating systems where file system is case sensitive, QTranslator also tries to load a lower-cased version of the locale name.

Definition at line 728 of file qtranslator.cpp.

References d, directory, find_translation(), and QString::isEmpty().

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◆ load() [2/3]

bool QTranslator::load	(	const QString &	filename,
		const QString &	directory = `QString()`,
		const QString &	search_delimiters = `QString()`,
		const QString &	suffix = `QString()`
	)

Loads filename + suffix (".qm" if the suffix is not specified), which may be an absolute file name or relative to directory.

Returns true if the translation is successfully loaded; otherwise returns false.

If directory is not specified, the current directory is used (i.e., as \l{QDir::}{currentPath()}).

The previous contents of this translator object are discarded.

If the file name does not exist, other file names are tried in the following order:

\list 1

File name without suffix appended.
File name with text after a character in search_delimiters stripped ("_." is the default for search_delimiters if it is an empty string) and suffix.
File name stripped without suffix appended.
File name stripped further, etc. \endlist

For example, an application running in the fr_CA locale (French-speaking Canada) might call load("foo.fr_ca", "/opt/foolib"). load() would then try to open the first existing readable file from this list:

\list 1

/opt/foolib/foo.fr_ca.qm
/opt/foolib/foo.fr_ca
/opt/foolib/foo.fr.qm
/opt/foolib/foo.fr
/opt/foolib/foo.qm
/opt/foolib/foo \endlist

Usually, it is better to use the QTranslator::load(const QLocale &, const QString &, const QString &, const QString &, const QString &) function instead, because it uses \l{QLocale::uiLanguages()} and not simply the locale name, which refers to the formatting of dates and numbers and not necessarily the UI language.

Definition at line 442 of file qtranslator.cpp.

References d, directory, dotQmLiteral(), QString::endsWith(), fi, i, QFileInfo::isFile(), QString::isNull(), QFileInfo::isReadable(), isRelative(), QStringLiteral, QFileInfo::setFile(), and QString::size().

Referenced by main(), and quick_test_main_with_setup().

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◆ load() [3/3]

bool QTranslator::load	(	const uchar *	data,
		int	len,
		const QString &	directory = `QString()`
	)

Definition at line 752 of file qtranslator.cpp.

References d, directory, magic, and MagicLength.

◆ translate()

QString QTranslator::translate	(	const char *	context,
		const char *	sourceText,
		const char *	disambiguation = `nullptr`,
		int	n = `-1`
	)		const

virtual

Returns the translation for the key (context, sourceText, disambiguation).

If none is found, also tries (context, sourceText, ""). If that still fails, returns a null string.

Note: Incomplete translations may result in unexpected behavior: If no translation for (context, sourceText, "") is provided, the method might in this case actually return a translation for a different disambiguation.

If n is not -1, it is used to choose an appropriate form for the translation (e.g. "%n file found" vs. "%n files found").

If you need to programmatically insert translations into a QTranslator, this function can be reimplemented.

See also: load()

Reimplemented in ProxyTranslator.

Definition at line 1082 of file qtranslator.cpp.

References context, and d.

Referenced by QCoreApplication::translate().

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

qtbase/src/corelib/kernel/qtranslator.h
qtbase/src/corelib/kernel/qtranslator.cpp

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QTranslator()

◆ ~QTranslator()

Member Function Documentation

◆ filePath()

◆ isEmpty()

◆ language()

◆ load() [1/3]

◆ load() [2/3]

◆ load() [3/3]

◆ translate()