🚀 go-pugleaf

"Jonathan Starr" <starr@belsoft.com> wrote in message
news:3f838962$1@newsgroups.borland.com...
> I have a Multiple Document Interface app.  I assign a handler for
> OnDragOver for the main form.   I run the app, and drag a file
> from the desktop to the app's main form.  The handler does not
> get called.

It is not supposed to be.  The OnDrag... events are only for the VCL's own
use when dragging VCL controls around within the application itself.  They
are not meant for interacting with the rest of the system at all.

For what you ask, you need to either:

1) call DragAcceptFiles() at program startup and then intercept WM_DROPFILES
messages, using DragQueryFile() and DragQueryPoint() to obtain information
about each dropped file (this is the easier way to go).

2)  Create your own IDropTarget-derived object and then call
RegisterDragDrop() at program startup and RevokeDragDrop() at program
termination.  When a drop occurs, your IDropTarget will be called into by
the system to handle the operation (this is the way Microsoft recommends
people to go).

All of this is documented in the Win32 API documentation.


Gambit