As an exercise, I updated Tim Crowson’s Multi_ImporterPPG addon with a DragAndDrop event, so you can import multiple files with a single drag-and-drop. You can download the modified version here.

Here’s the DragAndDrop event handler. The doit() function is also used by the Import menu command; I just had to generalize it a bit to work in either case (menu or drag-and-drop).

def Multi_Importer_DragAndDrop_OnEvent( in_ctxt ):

	action = in_ctxt.GetAttribute( "DragAndDropAction" )
	source = in_ctxt.GetAttribute( "DragSource" )

	if action == constants.siSourceDragAction:
		if re.search( r"\obj$", source, re.I ):
			in_ctxt.SetAttribute( "DragSourceSupported", True )
		elif re.search( r"fbx$", source, re.I ): 
			in_ctxt.SetAttribute( "DragSourceSupported", True )
		elif re.search( r"emdl$", source, re.I ): 
			in_ctxt.SetAttribute( "DragSourceSupported", True )
		elif re.search( r"lwo$", source, re.I ): 
			in_ctxt.SetAttribute( "DragSourceSupported", True )
		else:
			in_ctxt.SetAttribute( "DragSourceSupported", False )
		
	
	if action == constants.siSourceDropAction:

		Application.SetValue('preferences.Interaction.autoinspect', False, '')

		if not Application.ActiveSceneRoot.Properties( 'Multi_Importer' ):
			vtcol = Application.AddProp('Multi_Importer','Scene_Root')
			p = Application.Dictionary.GetObject( vtcol.Value("Value") )

			# Set the flag that hides certain parts of the PPG layout
			p.Parameters("bMenuCommand").Value = False

			# Inspect the PPG in modal mode
			Application.InspectObj( vtcol.Value("Value"), "", "", 4 )

			p.Parameters("bMenuCommand").Value = True
			
		p = Application.ActiveSceneRoot.Properties('Multi_Importer')

		options = { 
			'OBJgrouping' : p.Parameters('importOBJgrouping').Value,
			'OBJhrc' : p.Parameters('importOBJhrc').Value,
			'importOBJnormals' : p.Parameters('importOBJNormals').Value,
			'includeOBJmat' : p.Parameters('includeOBJMaterial').Value,
			'includeOBJuv' : p.Parameters('includeOBJUV').Value,
			'includeOBJwrap' : p.Parameters('includeOBJUVWrap').Value,
			'fbxScale' : p.Parameters('fbxScale').Value,
			'importEMDLasRef' : p.Parameters('importEMDLasRef').Value,
			'lwoScaleFactor' : p.Parameters('lwoScaleFactor').Value
			}
		
		doit( source, options )
	
	return True