内容

• 公共函数
• 详细描述

QSignalBlocker 类

异常安全包裹器围绕 QObject::blockSignals () 更多...

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

• 所有成员列表，包括继承成员

注意： 此类的所有函数 可重入 .

公共函数

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

详细描述

异常安全包裹器围绕 QObject::blockSignals ()

QSignalBlocker can be used whereever 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.

另请参阅 QMutexLocker and QEventLoopLocker .

成员函数文档编制

QSignalBlocker:: QSignalBlocker ( QObject * object )

Constructor. Calls object ->blockSignals(true).

QSignalBlocker:: QSignalBlocker ( QObject & object )

这是重载函数。

调用 object .blockSignals(true).

QSignalBlocker:: QSignalBlocker ( QSignalBlocker && other )

Move-constructs a signal blocker from other . other will have a no-op destructor, while repsonsibility for restoring the QObject::signalsBlocked () state is transferred to the new object.

QSignalBlocker:: ~QSignalBlocker ()

Destructor. Restores the QObject::signalsBlocked () state to what it was before the constructor ran, unless unblock () has been called without a following reblock (), in which case it does nothing.

void QSignalBlocker:: reblock ()

重新阻塞之后信号，基于先前 unblock ().

The numbers of reblock() and unblock () calls are not counted, so every reblock() undoes any number of unblock () calls.

void QSignalBlocker:: unblock ()

Temporarily restores the QObject::signalsBlocked () state to what it was before this QSignaBlocker's constructor ran. To undo, use reblock ().

The numbers of reblock () and unblock() calls are not counted, so every unblock() undoes any number of reblock () calls.

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

Move-assigns this signal blocker from other . other will have a no-op destructor, while repsonsibility for restoring the QObject::signalsBlocked () state is transferred to this object.

The object's signals this signal blocker was blocking prior to being moved to, if any, are unblocked except in the case where both instances block the same object's signals and *this is unblocked while other is not, at the time of the move.