Mouse.Button (gb.qt4)
Static Property Read Button As Integer
Return which button is pressed or released during a
MouseDown or
MouseUp event.
Be careful using this property to detect Right and Middle buttons if your program needs to be portable.
The underlying GUI toolkits report things differently.
GTK will show a value of 3 for Right mouse button and 2 for Middle
QT will show a value of 2 for Right mouse button and 3 for Middle
Both GTK and QT show a value of 1 for Left mouse button.