Can't use Qt::UniqueConnection in Qt connect-CodePudding

I have a connect statement that compiles fine, with connection type QueuedConnection. Once I OR it with UniqueConnection, it refuses to compile. I had to re-cast it back to Qt::ConnectionType for it to run. Is this normal/expected behaviour?

I thought the connection method definition would accept an int (which is equivalent to enum) without complaint.

connect(
    mySource, SIGNAL(mySig()),
    this, SLOT(mySlot())),
    static_cast<Qt::ConnectionType> 
    (Qt::QueuedConnection|Qt::UniqueConnection));

CodePudding user response：

I try this Example :

QPushButton *button = new QPushButton();
button->setText("Clicke me ");
ui->gridLayout->addWidget(button);

connect(button,&QPushButton::clicked,this,[](){
qDebug()<<"button is clicked";
}, Qt::UniqueConnection);

what you write In your connect is wrong, because you should follow this style :

connect(object,SIGNAL(mySig()), this,SLOT(mySlot())),Qt::QueuedConnection);

you can't use two Connections at the same time

From

CodePudding user response：

You have to explicitly choose one of the connection types, you cannot have multiple in one connection.

Check the doc for their differences: Qt connections types