problem with drag-dropping a text string

Peter Brigham pmbrig at
Fri Apr 11 10:29:16 EDT 2008

I still can't get it to work. Jacque, thanks for the tip about the  
allowableDragActions -- that makes the copy vs move part work  
reliably. But no matter what I do I can't set the dragdata (or the  
dragdata["text"]) to a modified text string and get it to drop into  
the target field. I've tried transforming the text in a dragStart  
handler per Eric's suggestion and setting the dragdata then, I've  
tried doing it in a dragEnter in the target field script. I even  
tried using a global, myDragData, that is set in the drag start and  
then in the dragenter handler I set the dragdata["text"] to  
myDragData. All fail. No matter what I do I have not been able to  
*set* the dragData or the dragData["text"] to any string and have it  
actually drop that string into my target field. It's acting as though  
the 'set the dragData...' command is ignored no matter where I try to  
do it.

Also, an empty dragDrop handler in the target field blocks the drop.  
Doesn't this mean that the dragDrop message is sent *before* the  
drop? So it still seems to me that if I could set the dragData at  
all, I ought to be able to do it in the dragDrop handler in the  
target field. Well, I'll take a look at the tutorial on the subject  
when I get a moment (I already have a full-time non-rev job...).

Could someone try setting the dragData["text"] to "finally got it to  
work!" and give me a recipe?

Peter M. Brigham
pmbrig at

> "J. Landman Gay" <jacque at> wrote:
>> Eric Chatonet wrote:
>>> Sounds better to set all this in a dragStart handler:
>>> on dragStart
>>>   set the dragImage to <ID>
>>>   [set the dragImageOffset to <point>]
>>>   set the dragData[<type>] to <data>
>>> end dragStart
>>> In your case: set the dragData["text"] to Transform(the
>>> dragData["text"]) -- specific function
>> That didn't work either until I remembered to set the
>> allowableDragActions. Then it worked.
>> Peter, try that. I was getting bizarre results too until I  
>> remembered to
>> set that property in a dragStart handler. It's a new keyword as of  
>> 2.9.
>> One thing I noticed. If I set the allowableDragActions to "move,copy"
>> (the example in the docs) or "copy,move" it will only move text,  
>> even if
>> the target field sets the dragaction to "copy".
>> -- 
>> Jacqueline Landman Gay         |     jacque at
>> HyperActive Software           |
> Peter M. Brigham wrote:
> I am trying to modify the dragdata before a text string is dropped,
> and it's not working, so I must be doing something wrong. The idea is
> for the user to select some text from one field (unlocked), and drag
> it to to a target field (unlocked), and I want to insert a tab in
> place of a space in the text and drop the modified text into the
> target field. Both fields are in the same group on the same card.
> Here's my script (in the target field):
> on dragDrop
>    set the dragaction to "copy"
>    put the dragData into mLine -- works fine, so does using the
> 'dragData["text"]'
>    set the itemdelimiter to tab
>    put item 2 of mLine into mChunk
>    put length(word 1 of mChunk) into w
>    put tab into char w+1 of mChunk
>    put mChunk into item 2 of mLine
>    set the dragdata to mLine
>    -- set the dragdata["text"] to mLine -- I tried this too
>    pass dragDrop
> end dragDrop
> There are no other handlers in the script, and no other dragdrop
> handlers in the group, card, or stack scripts.
> The original selected text is dropped without modification into the
> target field. The dragDrop handler is getting triggered, since
> setting a breakpoint and doing the drag-drop opens up the script in
> the debugger, and the data is manipulated correctly as I step through
> the script, so at the end mLine contains the proper string -- but the
> original string is what appears in the target field, even when I
> substitute 'set the dragdata to "something inane"'. So the command
> 'set the dragData to...' is being ignored, apparently.
> I tried instead modifying the dragdata in a dragStart handler in the
> starting field, but it seems that the dragdata is not yet set at that
> point, since "put the dragdata into mLine" shows mLine = empty in the
> debugger, which doesn't really make sense -- shouldn't the engine
> know by that point what the dragdata is?
> I tried putting a 'wait 25 millisecs with messages' line just after
> setting the dragdata, before passing the dragdrop, figuring maybe
> setting the dragdata property takes a little time for some reason
> (but why should it?) -- still no go.
> Uh oh, another problem -- suddenly, setting the dragAction to "copy"
> now doesn't work. I swear it was working before. I just tried setting
> the dragaction in a dragstart handler and in a dragleave handler in
> the starting field, as well as in the dragdrop handler in the target
> field, but in all cases the text is moved instead of being copied,
> unless of course I hold down the optionkey. I *swear* it was working
> properly before...! Oh -- the problem is the wait with messages
> command that I just put in -- this apparently allows the dragaction
> to reset to "none." When I take out the wait command the text is
> copied and not moved. Well, that's a relief. But the original problem
> remains.
> This is the first time I've messed around with drag/drop, but there
> seems to be a problem setting the dragddata. Is there something I'm
> overlooking? I'm using a Mac iBook G4, OSX 10.4.1, Studio 2.9 build
> 610. Running in the IDE -- but suspending development tools doesn't
> work, so it's not an obvious IDE problem. Restarting Rev didn't do it
> either. Help!

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