added GetButton(), some cleanups

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@14309 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/latex/wx/mouseevt.tex

@@ -1,7 +1,12 @@
 \section{\class{wxMouseEvent}}\label{wxmouseevent}
 
-This event class contains information about mouse events.
-See \helpref{wxWindow::OnMouseEvent}{wxwindowonmouseevent}.
+This event class contains information about the events generated by the mouse:
+they include mouse buttons press and release events and mouse move events.
+
+All mouse events involving the buttons use $1$ for the left mouse button, $2$
+for the middle one and $3$ for the right one. Note that not all mice have
+a middle button so a portable application should avoid relying on the events
+from it.
 
 {\bf NB: } Note that under Windows mouse enter and leave events are not natively supported
 by the system but are generated by wxWindows itself. This has several
@@ -167,9 +172,6 @@ Returns TRUE if the identified mouse button is changing state. Valid
 values of {\it button} are 1, 2 or 3 for left, middle and right
 buttons respectively.
 
-Not all mice have middle buttons so a portable application should avoid
-this one.
-
 \membersection{wxMouseEvent::ButtonDClick}\label{buttondclick}
 
 \func{bool}{ButtonDClick}{\param{int}{ but = -1}}
@@ -214,6 +216,15 @@ Returns TRUE if the mouse was entering the window.
 
 See also \helpref{wxMouseEvent::Leaving}{wxmouseeventleaving}.
 
+\membersection{wxMouseEvent::GetButton}\label{wxmouseeventgetbutton}
+
+\constfunc{int}{GetButton}{\void}
+
+Returns the mouse button which generated this event or $-1$ if no button is
+involved (for mouse move, enter or leave event, for example). The value $1$ is
+returned for the left button down, up and double click events, $2$ and $3$ for
+the same events for the middle and the right buttons respectively.
+
 \membersection{wxMouseEvent::GetPosition}\label{wxmouseeventgetposition}
 
 \constfunc{wxPoint}{GetPosition}{\void}