QSignalBlocker

QSignalBlocker Class

Exception-safe wrapper around QObject::blockSignals(). More...

Header:	#include <QSignalBlocker>
qmake:	QT += core
Since:	Qt 5.3

List of all members, including inherited members

Note: All functions in this class are reentrant.

Public Functions

	QSignalBlocker(QObject *o)
	QSignalBlocker(QObject &o)
	QSignalBlocker(QSignalBlocker &&other)
	~QSignalBlocker()
void	reblock()
void	unblock()
QSignalBlocker &	operator=(QSignalBlocker &&other)

Detailed Description

Exception-safe wrapper around QObject::blockSignals().

QSignalBlocker can be used wherever you would otherwise use a pair of calls to blockSignals(). It blocks signals in its constructor and in the destructor it resets the state to what it was before the constructor ran.


  {
  const QSignalBlocker blocker(someQObject);
  // no signals here
  }

is thus equivalent to


  const bool wasBlocked = someQObject->blockSignals(true);
  // no signals here
  someQObject->blockSignals(wasBlocked);

except the code using QSignalBlocker is safe in the face of exceptions.

See also QMutexLocker and QEventLoopLocker.

Member Function Documentation

QSignalBlocker::QSignalBlocker(QObject *o)

Default constructs an instance of QSignalBlocker.

QSignalBlocker::QSignalBlocker(QObject &o)

Default constructs an instance of QSignalBlocker.

QSignalBlocker::QSignalBlocker(QSignalBlocker &&other)

Move-copy constructor.

QSignalBlocker::~QSignalBlocker()

Destroys the instance of QSignalBlocker.

void QSignalBlocker::reblock()

void QSignalBlocker::unblock()

QSignalBlocker &QSignalBlocker::operator=(QSignalBlocker &&other)

Move-assignment operator.

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