message path and other errors (long post)

Kurt Kaufman kkaufman at
Wed Apr 23 19:38:01 CDT 2003

[This long bug report is something I probably wouldn't post to the list 
except that since the stack in question is distributed with the Rev. 2 
beta, it could be easily tested by others, if they are so inclined, and 
so might be useful in tracking down some potential problems in the 
current beta.]

Rev. 2 beta 2
Mac OS 10.2.5
Stack:  "MIDIBuilder" version 020915 (included as Rev. 2 sample stack)

I have in the (single) card script, in the handler for the "mousedown" 
event,  the function "playAtOnce".
The handler for playAtOnce is located outside of the mousedown handler, 
but on the same card script. In Rev 1.1.1, the message is handled as I 
expected with no apparent errors.  But in Rev 2, the following error is 
generated each time a mousedown event occurs:

Type	Handler: can't find handler
Object	playAtOnce
Hint	playStarted

The error is not such that activity stops, since the stack continues to 
function as expected, i.e. the function playAtOnce does execute.

Have there been any changes made to the message path such that a 
handler arranged as above is now "incorrect"?

A few other errors, probably unrelated:

1) Visible field problem:

There is a "Help" field which is hidden on startup (just in case the 
stack previously crashed with the field visible):

on preopencard
hide field "Help"
end preopencard

Oddly, once when I attempted to open MIDIBuilder, it opened with the 
Help field visible, and even though the field has the mouseup handler 
"hide me", no amount of clicking on the field (or setting its visible 
property to false) would hide it.  I then quit and reopened it in Rev, 
2, still experiencing the same problem.  I subsequently opened the same 
stack in Rev. 1.1.1, and the field was properly hidden.  Upon reopening 
it in Rev. 2, the field was hidden.
Since then I have not been able to recreate this problem.

2) inadvertent menuitem "adjustments":

In MIDIBuilder there is a popup menu "Meter" which contains the 
following script:

on menupick theMeter
   switch theMeter
   case "2\4"
     put binaryEncode("H8","02021808") after gMidMeter
   case "3\4"
     put binaryEncode("H8","03021808") after gMidMeter
   end switch
end menupick

When the stack is first opened the menu appears as "4/4" (the default). 
  But the first time there is a mousedown upon the menu, all of its four 
menuitems lose their "/" character, i.e. "2/4" becomes "24"; "3/4" 
becomes "34", etc.  -Big problem, since a MIDI file cannot be generated 
without appropriate data that is added based on the selection of one of 
the specific menuitems as I wrote them.

I note that in the "What's New" file, we have the following:
- Placing a backslash (\) before menu metacharacters such as "(" now 
escapes those characters, so that they are shown as-is in the menu.

Could this have something to do with the inadvertent menu "adjustments" 

3)  QT player object problems

When playing a MIDI file (as a MIDI sequence preview in MIDIBuilder, 
for instance) or an audio file (an audio "movie") in a QT player 
object, the "controller thumb" does not scroll horizontally with the 
progress of the playing file.  I note the problem is previously 
identified with QT 5; this happens with QT 6.1.1.


More information about the use-livecode mailing list