Rollover tooltip - code.
I don't know if this is exactly what you're looking for, but this snippet from @Anonymous shows how to add somethin in the AutoCAD tooltip.
/// PointMonitorClient.cs Copyright(c) 2009 Tony Tanzillo
/// CaddZone AutoCAD Programming Samples - PointMonitorClient.cs
///
/// This sample code shows how to use the Editor's PointMonitor
/// event to display information about the entity currently under
/// the pickbox in AutoCAD's tooltip.
///
/// In this example, we display the length of the Curve object
/// which the pickbox is hovering over, but in practicle use you
/// may display anything at all about any type of object(s).
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.DatabaseServices;
using Acad = Autodesk.AutoCAD.ApplicationServices.Application;
[assembly: ExtensionApplication(typeof(PointMonitorToolTipExample.PointMonitorClient))]
namespace PointMonitorToolTipExample
{
// IExtensionApplication
public class MyApplication : IExtensionApplication
{
public void Initialize()
{
PointMonitorClient.Initialize();
}
public void Terminate()
{
}
}
internal class PointMonitorClient
{
// This is a dummy method that invokes the static constructor
// below. We place code that should never run more than once in
// the static constructor, because .NET guarantees us that a
// static c'tor will never run multiple times.
public static void Initialize()
{
}
// Handle the PointMonitor event of all currently open documents,
// and add event handlers to manage the point monitor events of
// all subsequently opened and closed documents:
// Static constructor
static PointMonitorClient()
{
Acad.DocumentManager.DocumentCreated += documentCreated;
Acad.DocumentManager.DocumentToBeDestroyed += documentToBeDestroyed;
foreach (Document doc in Acad.DocumentManager)
doc.Editor.PointMonitor += pointMonitor;
}
// The DocumentCreated event handler adds the PointMonitor event handler
// to each subsequently-opened document:
static void documentCreated(object sender, DocumentCollectionEventArgs e)
{
if (e.Document != null)
e.Document.Editor.PointMonitor += pointMonitor;
}
// The DocumentToBeDestroyed event handler removes the PointMonitor
// event handler from each document when it is closing:
static void documentToBeDestroyed(object sender, DocumentCollectionEventArgs e)
{
if (e.Document != null)
e.Document.Editor.PointMonitor -= pointMonitor;
}
// The PointMonitor Event Handler
static void pointMonitor(object sender, PointMonitorEventArgs e)
{
// For this purpose we ignore events triggered by keyboard input:
if ((e.Context.History & PointHistoryBits.FromKeyboard) == PointHistoryBits.FromKeyboard)
return;
// Get all entities in the aperture target:
FullSubentityPath[] paths = e.Context.GetPickedEntities();
// If none were found, bail out
if (paths == null || paths.Length == 0)
return;
// There will be one FullSubentityPath in the array for each
// top-level entity in the aperture target, so when there's
// multiple entities in aperture target, we must select the
// correct one.
//
// The first ObjectId in the first FullSubEntityPath (if there's
// more than one) is the entity that should be highlighted by
// rollover highlighting, so we use that same object here. Note
// that this example does not support nested objects even though
// that's possible given the data returned by GetPickedEntities().
ObjectId[] ids = paths[0].GetObjectIds();
if (ids == null || ids.Length == 0)
return;
ObjectId id = ids[0]; // The first ObjectId is the top-level entity
// Use the RXClass returned by the ObjectId's ObjectClass property
// to determine if the object is a Curve. Note that this is a more
// efficient way to query the type of an object, verses opening it
// and examining its managed wrapper type:
if (id.IsValid && id.ObjectClass.IsDerivedFrom(curveClass))
{
// Start a transaction:
using (Transaction tr = id.Database.TransactionManager.StartTransaction())
{
// Open the object and cast it to a Curve:
Curve curve = tr.GetObject(id, OpenMode.ForRead) as Curve;
// Try to get the curve's length:
double length = curve.TryGetLength(-1.0);
// If a valid length was returned, then
// convert it to current distance units
// format and add that to the tooltip text:
if (length > 0.0)
{
e.AppendToolTipText(
string.Format(
"Curve length: {0}",
Converter.DistanceToString(length)));
}
tr.Commit();
}
}
}
static RXClass curveClass = RXObject.GetClass(typeof(Curve));
static RXClass blockRefClass = RXClass.GetClass(typeof(BlockReference));
}
public static class ExtensionMethods
{
// This extension method returns the length of any curve
// which has a valid length (Rays and XLines do not have
// a length, or more precisely, are of infinite length, so
// we must deal with those as well as various other cases).
// When a curve doesn't have a valid length or is of infinite
// length, an exception is thrown by one of the members used
// here, so we just catch the exception and return the default
// parameter.
// Note that some curves (namely arcs and elliptical arcs)
// do not necessarily have a start parameter of 0.0, which
// means their length is the distance from the start param
// to the end param, so we must subtract the distance to the
// point at the start param from the distance to the point
// at the end param to ensure we get the actual length:
public static double TryGetLength(this Curve curve, double defaultValue)
{
try
{
return Math.Abs(curve.GetDistanceAtParameter(curve.EndParam) - curve.GetDistanceAtParameter(curve.StartParam));
}
catch
{
return defaultValue;
}
}
public static int CountInsertsInSpace(this BlockTableRecord btr, ObjectId spaceId)
{
int cnt = 0;
foreach (ObjectId brId in btr.GetBlockReferenceIds(true, false))
{
BlockReference br = (BlockReference)brId.GetObject(OpenMode.ForRead);
if (br.OwnerId == spaceId) cnt++;
}
return cnt;
}
}
}
Besides the code posted by @_gile, If you want to make the rollover tooltip more presentable, you may want to read this article of mine posted about 2 years ago:
https://drive-cad-with-code.blogspot.com/2016/12/custom-autocad-entity-tool-tip.html
assuming you know AutoCAD .NET API programming well.
Now, after second reading of your original post and your reply, it seems you are not interested in doing your own rollowner tip in AutoCAD.
So, I am not sure what you want and what does "... get the code for the rollover tooltip..." mean, especially, what does "code" mean here? Also. if you want to do something similar to AutoCAD's rollover tip in different application other than AutoCAD, I am afraid nothing discussed in this forum would help you, because all things discussed USE APIs provided by AutoCAD and HAVE TO BE running in AutoCAD.