Passing QLabel as a parameter in Qt Creator gives error

Question

I am trying to pass a QLabel as a parameter to another function that is supposed to change the style of the label:

main
{
...
setSeatColor(ui->lblPan2Seat5B, 2);

}


void setSeatColor(QLabel& lbl, int i)
{
   if(i == 1)
   {
    lbl.setStyleSheet("QLabel { background-color : blue; color : white; }");
   }
   else if(i == 2)
   {
    lbl.setStyleSheet("QLabel { background-color : red; color : white; }");
   }
   else if(i == 3)
   {
    lbl.setStyleSheet("QLabel { background-color : green; color : white; }");
   }
   else
   {
    lbl.setStyleSheet("QLabel { background-color : rgb(240,240,240); color : back; }");
   }
}

The error in the function:

"No matching function for call to setSeatColor(QLabel*&,int)"

Your help is much appreciated!

Answer 1

You pass a QLabel pointer to a function that takes a QLabel&, so replace this call:

setSeatColor(ui->lblPan2Seat5B, 2);

with this one (notice the dereference operator *)

setSeatColor(*ui->lblPan2Seat5B, 2);

//you can use extra parentheses for your colleagues, so that they can understand what are you doing there: setSeatColor( *(ui->lblPan2Seat5B), 2); - that way is a little clearer that you intend to dereference the lblPan2Seat5B not the ui that is dereferenced by the -> operator