[Oberon] Defining code for MM + MR

[mcintosh at vima.austin.tx.us]

In V4, the "Viewers" each have "Handlers" and it is the
procedure Handle where the MM+MR interclick is interpreted.

I looked at the S3 (BlueBottle 5/22/02) procedure TextFrames.Handle, which 
handles the type Oberon.InputMsg with the procedure TextFrames.Edit.  
In that procedure, the keys variable handles the various mouse clicks.

The MM+MR command, for example, is located deep under
    IF X < F.X + Min(F.left, barW) THEN
    ...
    ELSE
    ...
      ELSIF 1 IN Keys THEN
      ...
          IF (pos >= 0) & ~(2 IN keysum) THEN CallCmd(OpenCmd, F, pos, FALSE) END


One thing that this means is that each type of Viewer, and indeed each frame in a viewer, has a
custom action for the MM+MR command.  In principle, I could have one text open with two viewers
and have two different actions for the MM+MR key sequence.  (Hopefully, they would both 
be conceptually some type of "Open" action.


Aubrey McIntosh <mcintosh at vima.austin.tx.us>
Assistant Professor of Chemistry
University of Minnesota, Morris
600 E. 4th St.
Morris, MN 56267-2134