Pre- and Post-Picking Objects
Windows only
Overview
The normal operation for commands that manipulate geometric objects is to allow the user to either pre-pick or post-pick the objects. Occasionally, though, it might be necessary for commands to want to allow for both pre-picked and post-picked objects. That is, after it has been determined that objects were pre-picked, allow the user to continue to pos-pick more objects.
Sample
The following code sample demonstrates this capability…
CRhinoCommand::result CCommandTest::RunCommand( const CRhinoCommandContext& context )
{
bool bObjectsWerePreSelected = false;
bool bObjectsWerePostSelected = false;
ON_SimpleArray<const CRhinoObject*> obj_list;
// Select some objects. Allow for pre-selected objects
CRhinoGetObject go;
go.SetCommandPrompt( L"Select objects" );
go.EnablePreSelect( TRUE );
go.GetObjects( 0, 0 );
if( go.CommandResult() != CRhinoCommand::success )
return go.CommandResult();
// Add the selected objects to our list
int i;
for( i = 0; i < go.ObjectCount(); i++ )
{
const CRhinoObjRef& objref = go.Object(i);
const CRhinoObject* obj = objref.Object();
if( obj )
obj_list.Append( obj );
}
// Determine of the bjects were pre-selected
// or post-selected.
if( go.ObjectsWerePreSelected() )
bObjectsWerePreSelected = true;
else
bObjectsWerePostSelected = true;
// If objects were pre-selected, then select
// more objects. But, ignore pre-selected ones.
if( bObjectsWerePreSelected )
{
go.EnablePreSelect( FALSE );
go.EnableDeselectAllBeforePostSelect( FALSE );
go.GetObjects( 0, 0 );
if( go.CommandResult() != CRhinoCommand::success )
return go.CommandResult();
for( i = 0; i < go.ObjectCount(); i++ )
{
const CRhinoObjRef& objref = go.Object(i);
const CRhinoObject* obj = objref.Object();
if( obj )
obj_list.Append( obj );
}
bObjectsWerePostSelected = true;
}
if( obj_list.Count() == 0 )
return CRhinoCommand::nothing;
//
// TODO: do something with the object list here
//
// The normal behavior of commands is that when they finish,
// objects that were pre-selected remain selected and objects
// that were post-selected will not be selected. Because we
// potentially could have both, we'll try to do something
// consistent.
if( bObjectsWerePreSelected && bObjectsWerePreSelected )
{
for( i = 0; i < obj_list.Count(); i++ )
{
const CRhinoObject* obj = obj_list[i];
if( obj && obj->IsSelected() )
obj->Select( false );
}
context.m_doc.Redraw();
}
return CRhinoCommand::success;
}