<![CDATA[Passing Parameters to Slots]]>A slot seems to work as expected without a parameter passed to it as follows:

@ connect (ui->pushButton, SIGNAL (clicked()), this, SLOT(goal_seek()));

//...code...

void MainWindow::goal_seek()
{
double seek = 5;
QTableWidgetItem *itab7= new QTableWidgetItem;
QString A2 = QString::number(seek);
itab7->setText(A2);
ui->tableWidget_2->setItem(0,7, itab7);
}
@

However, when I use the same code, the slot does not work with the parameter passed to it, as shown below:

@
connect (ui->pushButton, SIGNAL (clicked()), this, SLOT(goal_seek(5.0)));

void MainWindow::goal_seek(double seek)
{
double seek = 5;
QTableWidgetItem *itab7= new QTableWidgetItem;
QString A2 = QString::number(seek);
itab7->setText(A2);
ui->tableWidget_2->setItem(0,7, itab7);
}
@

Can one use parameters for slots, and if so, how?

]]>https://forum.qt.io/topic/37976/passing-parameters-to-slotsRSS for NodeSat, 05 Sep 2026 14:06:27 GMTTue, 18 Feb 2014 11:41:36 GMT60<![CDATA[Reply to Passing Parameters to Slots on Tue, 18 Feb 2014 13:53:18 GMT]]>One of solutions is:
@ connect (ui->pushButton, SIGNAL (clicked()), this, SLOT(some_slot()));
//code...
void MainWindow::some_slot()
{
goal_seek(5);
}
@
or
@
connect (ui->pushButton, SIGNAL (clicked()), this, SLOT(some_slot()));
connect (ui->pushButton, SIGNAL (clicked(int)), this, SLOT(goal_seek(int)));
//code...

void MainWindow::some_slot()
{
emit clicked(5);
}
@
it depends from your code structure.

]]>https://forum.qt.io/post/215306https://forum.qt.io/post/215306Tue, 18 Feb 2014 13:53:18 GMT<![CDATA[Reply to Passing Parameters to Slots on Tue, 18 Feb 2014 12:13:52 GMT]]>It doesn't work. Where does the emit code go?

]]>https://forum.qt.io/post/215297https://forum.qt.io/post/215297Tue, 18 Feb 2014 12:13:52 GMT<![CDATA[Reply to Passing Parameters to Slots on Tue, 18 Feb 2014 12:00:06 GMT]]>You are doing it wrong. You can't pass static values to slots in the connect assignment. You need to emit a value together with your signal:
@
// header
signals:
void clicked(int) const;

// source
connect (usomeObject, SIGNAL (clicked(int)), this, SLOT(goal_seek(int)));

// signal emission:
emit clicked(5);
@

]]>https://forum.qt.io/post/215294https://forum.qt.io/post/215294Tue, 18 Feb 2014 12:00:06 GMT