Detecting a "grabEnter"?

Eric Chatonet eric.chatonet at
Thu Sep 4 13:16:09 CDT 2008

Bonsoir David,

When you use Rev 2.9 feature, Rev sets the blendlevel of the  
dragImage you specified to a value that makes it enough transparent  
to see what you hover when dragging.
This blend level can't be specified and is set by the engine.
If you accept it, it might solve your problem because you no longer  
drag a Rev object then objects on the current card receive dragEnter  
and dragLeave messages you can easily handle.
If you don't accept this automated blend level, run you own and  
detect where is the mouseloc.

"How to manage drag and drop #2" tutorial might help you:
This stack explores all ways to manage Drag and Drop especially with  
Rev 2.9 new features:
In one Rev window, between two Rev windows, from Rev or towards Rev  
with text, images, files, etc.
How to create a drag image on-the-fly, a tools palette and many other  
Scripts fully commented.

You will access this tutorial through "Tutorials Picker" a free  
plugin that interfaces with the So Smart Software website in order to  
display all available tutorials stacks directly from the web.
You will find it by going to
Revolution/Plugins or Tutorials section.

Best regards from Paris,
Eric Chatonet.
Plugins and tutorials for Revolution:
Email: eric.chatonet at

Le 4 sept. 08 à 19:55, dfepstein at a écrit :

> Bonjour Eric,
> Your suggestion is intriguing but I haven't understood it.  What is  
> an "automatic blend level"?  If by script I set the dragged  
> object's blendLevel to 50, I still do not detect a mouseEnter when  
> it's dragged over another object.
> Many thanks.
> David Epstein
>> Bonjour David,
>> Actually, 2.9 drag and drop feature is able to solve your problem if
>> you accept dragged object's automatic blend level.
>> Le 4 sept. 08 à 15:49, dfepstein at a écrit :
>>> My question about "grabEnter" has led to an interesting broader
>>> discussion of the relative merits of grab vs mouseMove..
>>> I would be happy to write a more complicated "mouseMove"-controlled
>>> script, but as far as I can tell that won't solve the problem I
>>> posed. If the user is dragging an object, whether using "grab" or
>>> by a script reacting to "mouseMove" events, no objects beneath that
>>> object receive a mouseEnter or mouseLeave message, because the
>>> mouse remains within the object being dragged.
>>> I can think of ways of amending Transcript that would solve this
>>> problem--probably by extending the current usage of the various
>>> messages associated with drag and drop actions. But is there any
>>> way to do what I want with the language as it is? Capturing
>>> "mouseMove" doesn't tell me "what control the dragged object has
>>> just moved on top of" unless at each nudge of the mouse I compare
>>> the mouseLoc with the rectangles of all potential target objects.
>>> David Epstein

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