[Interest] mouse events: how to handle left and right button pressed?

[Rui Maciel]

I'm trying to handle mouse events which include the case where multiple 
mouse buttons are pressed. The reference page on QMouseButton[1] states 
that "[t]he button state is a combination of Qt::LeftButton 
<http://doc.qt.nokia.com/4.7/qt.html#MouseButton-enum>, Qt::RightButton 
<http://doc.qt.nokia.com/4.7/qt.html#MouseButton-enum>, Qt::MidButton 
<http://doc.qt.nokia.com/4.7/qt.html#MouseButton-enum> using the OR 
operator." From this, it would be expected that an event where multiple 
buttons were pressed would be handled in a way similar to the following 
code:


<code>
switch(event->buttons() )
{
case Qt::LeftButton:
std::cerr << "left" << std::endl;
break;

case Qt::RightButton:
std::cerr << "right" << std::endl;
break;

case (Qt::LeftButton | Qt::RightButton):
std::cerr << "both" << std::endl;
break;

default:
std::cerr << "other" << std::endl;
break;
}
</code>

Yet, when I try to compile this code, the following error message is 
displayed:

<message>
InputState.c++:22:41: error: temporary of non-literal type 
‘QFlags<Qt::MouseButton>’ in a constant expression
</message>


Does anyone know if it's possible to handle mouse events with multiple 
buttons pressed through a switch() statement? If it isn't possible then 
what alternatives are available?


Thanks in advance,
Rui Maciel

[1] http://doc.qt.nokia.com/4.7/qmouseevent.html#buttons