Using custom contextual ribbon tabs

By Adam Nagy

In AutoCAD when you start editing an MTEXT, then a Text Editor contextual tab appears in the Ribbon. How could I do something similar myself? E.g. when the user selects my custom entity then my own contextual tab would appear.

Solution

If you already have a contextual tab and you want to hook it up, so that it is shown under certain conditions then this is what you have to do.

1) You have to create a contextual selection rule xaml file.
You need to name it in a way that it ends with ContextualTabSelectorRules.xaml and starts with something that makes it unique. The best thing is to use your Registered Developer Symbol for that purpose
[RDS – Registered Developer Symbol: visit http://www.autodesk.com/developer and select Symbol Registration]
So mine would be AEN1ContextualTabSelectorRules.xaml

You can have a look at the [AutoCAD install folder]AcContextualTabSelectorRules.xaml file for ideas on what our xaml needs to contain.

On Vista and Windows 7 be careful if you copy and edit the AcContextualTabSelectorRules.xaml file. In that case take care about disabling the UAC when editing the copied file: with UAC enabled the copy operation works (requests administrator rights) but the editing writes transparently into the VirtualStore (because of limited rights), i.e. the original file is still just the copy and the subsequent changes are in a different place and only visible to the editor.

2) In the rule you create you can either use already available functions like Selection.ContainsOnly("Arc") or create your own assembly with some utility functions and use them from the selector rules file. That’s what we’ll do in this sample.
As you can see we will create an assembly called Aen1Helper with a Functions class that has a static function called ShowMyTab and then we can use it in the Aen1ContextualTabSelectorRules.xaml file the following way:

Aen1Helper.Functions.ShowMyTab(Selection)            ]]>

3) Then create a simple Class Library in Visual Studio which references acmgd.dll, acdbmgd.dll and WindowsBase assemblies [make sure that Copy Local is set to false for all of them]. You could implement any logic for controlling the appearance of your tab, but we’ll do something simple. Our rule will be based on the type of entity being selected and the name of the current document.

using System;         using Autodesk.AutoCAD.Windows.Data;    using Autodesk.AutoCAD.DatabaseServices;    using Autodesk.AutoCAD.ApplicationServices;         namespace Aen1Helper    {      public class Functions      {        public static bool ShowMyTab(object selObj)        {          Selection sel = (Selection)selObj;          if (sel.Count < 1 || !sel.ContainsOnly(new string[] {"Line"}))            return false;               if (Application.DocumentManager.MdiActiveDocument.            Name.EndsWith("Drawing1.dwg"))            return true;               return false;        }      }    }

4) Once both AEN1ContextualTabSelectorRules.xaml and Aen1Helper.dll have been placed in the AutoCAD install folder you can start AutoCAD and go into the CUI dialog to associate your rule with your contextual tab. Mine is called Aen1Tab.
Just drag Ribbon > Tabs > Aen1Tab onto Ribbon > Contextual Tab States > Aen1 Selection Rule and click OK
Now when you select a line in a document whose name ends with Drawing1.dwg then Aen1 Tab will appear