Weird script behaviour (was libUrlDownloadToFile & urlProgress)

J. Landman Gay jacque at
Wed Mar 23 17:32:31 EDT 2011

On 3/23/11 4:41 AM, Gerry wrote:
> This is the script that calls the handler:
> on mouseup
> set the blendLevel of me to "10"
> updateSongsList
> end mouseup

Where is the button located? On the card? In a group?

> This is the handler that it calls (I've xxxx'd out some domain details):
> on updateSongsList
> local songsOnDevice, songListOnServer
> play empty
> hide button "stopButton"
> put "Checking for updates..." into field "messages"
> put url "" into
> songListOnServer
> put the dgText of group "Songs" into songsOnDevice
> if the number of lines in songListOnServer>  the number of lines in
> songsOnDevice then
> put "Update received!" into field "messages"
> wait 120
> set the dgText of group "Songs" to songListOnServer
> set the defaultFolder to specialFolderPath("Documents")
> put songsOnServer into URL ("file:songs.txt")
> else
> put "No update received. Rats." into field "messages"
> wait 120
> end if
> put "" into field "messages"
> end updateSongsList

I don't see anything untoward there. Something else is going on.

> As I said previously, this script is not executed if it's in the card
> script, but does when it's in the stack script. That's weird enough,

It's explainable if the button is farther back in the message hierarchy 
than the card. The message path gets a little convoluted in background 

> but if I place it in the card script and I use "Send updateSongsList
> to this card" in the button script it starts executing the card script
> from the top, and I can track that by setting a breakpoint against the
> send command - it jumps from the button script into the card script,
> and I can step through all the lines in that card script, executing
> them as I go.
> Like I said, totally crazy!

Did you happen to insert the card script into the message path?

If it isn't already, try moving your button so that it sits directly on 
the card itself, not in any group. Keep its mouseup handler the way you 
have it above. That will put the card into the message path. Put your 
updateSongsList handler in the card.

I'm not sure what's going on, but it sounds like some kind of message 
path conflict coupled with some kind of recursion.

Jacqueline Landman Gay         |     jacque at
HyperActive Software           |

More information about the use-livecode mailing list