OnDragEnter picture event

Declaration
 ENTRY OnDragEnter(IN INT _refId, OUT BOOL _bAllow)
 ; akcie
 END OnDragEnter

Parameters
_refId For global handler - identifier of target graphic object.
_bAllow Defines whether a graphic object is able to process Drop operation.

Description
Picture event is generated over a target graphic object when a user moves the mouse cursor on it for the first time during Drag operation.
There must be determined whether the target graphic object is able to process Drop operation. This can be done globally, if the graphic object cannot take a role of the target object, or based on the format of transferred data. The format can be get by the function %IsDragData.
If the data format is suitable for processing in the graphic object, the target object should enable Drop operation through the parameter _bAllow. Based on this value, a mouse cursor icon, which indicates the possible completion of Drop operation, will be set.
Example
 ENTRY OnDragEnter (IN INT _refID, OUT BOOL _bAllow)
 
 ; test on admissibility of target object
 _bAllow := @FALSE
 
 ; what type of data I have? I can work only with a text
 IF %IsDragData(0, _DF_TEXT) THEN
 _bAllow := @TRUE
 END IF 
 END OnDragEnter

Related pages:

ENTRY - picture event handler
Active picture events

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