Topic: Selection of single entity of certain type

[MickD]

Hi All,

pretty much related to this thread but more pointed at what I'm trying to do http://www.theswamp.org/index.php?topic=39799.msg450962#msg450962

I haven't worked with selection sets with filters much in the past and I normally use GetEntity for single objects - no problem there.
Now I need to select a single object of a certain type and GetSelection with options and a filter sounds like it should work.

The way I understand it, if I set the SingleOnly and/or SinglePickInSpace properties to true I should only be able to select one item (and preferably not by selection window).

The filter is also failing as I can select not only multiple entities but I can select any entity type as well.

Code - C#: [Select]

1.         [CommandMethod("test")]
2.         public static void testSinglePick()
3.         {
4.             PromptSelectionOptions pso = new PromptSelectionOptions();
5.             pso.MessageForAdding = "Select a single POLYLINE object:\n";
6.             pso.MessageForRemoval = "Wrong selection, try again.";
7.             pso.SinglePickInSpace = true;
8.             pso.SingleOnly = true;
9.             TypedValue[] filterList = new TypedValue[1]{
10.                         new TypedValue((int) DxfCode.Start, "*POLYLINE"),
11.                     };
12.             SelectionFilter filter = new SelectionFilter(filterList);
13.             var ed = Bricscad.ApplicationServices.Application.DocumentManager.MdiActiveDocument.Editor;
14.             var promptResult = ed.GetSelection(pso, filter);
15.             ed.WriteMessage("You selected {0} objects.\n", promptResult.Value.Count);
16.         }
17.  

Thank you,
Mick

[Jeff H]

Hi Mick,
I am pretty sure I got idea from gile
but I use

Code - C#: [Select]

1.                 AllowedClassFilter acf = new AllowedClassFilter(typeof(BlockReference));
2.                 PromptSelectionResult psr = Ed.GetSelection(acf);
3.  

with

Code - C#: [Select]

1.     public class AllowedClassFilter
2.     {
3.         /// <summary>
4.         /// The PTRS
5.         /// </summary>
6.         private HashSet<IntPtr> ptrs = new HashSet<IntPtr>();
7.  
8.         /// <summary>
9.         /// Gets the allowed class PTRS.
10.         /// </summary>
11.         /// <value>
12.         /// The allowed class PTRS.
13.         /// </value>
14.         internal ICollection<IntPtr> AllowedClassPtrs { get { return ptrs; } }
15.  
16.         /// <summary>
17.         /// Initializes a new instance of the <see cref="AllowedClassFilter"/> class.
18.         /// </summary>
19.         /// <param name="types">The types.</param>
20.         public AllowedClassFilter(params Type[] types)
21.         {
22.             foreach (Type typ in types)
23.             {
24.                 AddAllowedClass(typ);
25.             }
26.         }
27.  
28.         /// <summary>
29.         /// Adds the allowed class.
30.         /// </summary>
31.         /// <param name="type">The type.</param>
32.         public void AddAllowedClass(Type type)
33.         {
34.             ptrs.Add(RXClass.GetClass(type).UnmanagedObject);
35.         }
36.     }
37.  

And extension methods to call it

Code - C#: [Select]

1.   public static PromptSelectionResult GetSelection(this Editor ed, PromptSelectionOptions options, AllowedClassFilter classFilter)
2.         {
3.             return ed.GetSelection((PromptSelectionOptions)null, classFilter);
4.         }
5.  
6.         /// <summary>
7.         /// Gets the selection.
8.         /// </summary>
9.         /// <param name="ed">The ed.</param>
10.         /// <param name="filter">The filter.</param>
11.         /// <param name="classFilter">The class filter.</param>
12.         /// <returns></returns>
13.         public static PromptSelectionResult GetSelection(this Editor ed, SelectionFilter filter, AllowedClassFilter classFilter)
14.         {
15.             return ed.GetSelection((SelectionFilter)null, classFilter);
16.         }
17.  
18.         /// <summary>
19.         /// Gets the selection.
20.         /// </summary>
21.         /// <param name="ed">The ed.</param>
22.         /// <param name="classFilter">The class filter.</param>
23.         /// <returns></returns>
24.         public static PromptSelectionResult GetSelection(this Editor ed, AllowedClassFilter classFilter)
25.         {
26.             return ed.GetSelection((PromptSelectionOptions)null, (SelectionFilter)null, classFilter);
27.         }
28.  
29.         /// <summary>
30.         /// Gets the selection.
31.         /// </summary>
32.         /// <param name="ed">The ed.</param>
33.         /// <param name="options">The options.</param>
34.         /// <param name="filter">The filter.</param>
35.         /// <param name="classFilter">The class filter.</param>
36.         /// <returns></returns>
37.         public static PromptSelectionResult GetSelection(this Editor ed, PromptSelectionOptions options, SelectionFilter filter, AllowedClassFilter classFilter)
38.         {
39.             AllowedClassPtrs = classFilter.AllowedClassPtrs;
40.             ed.SelectionAdded += new SelectionAddedEventHandler(ed_ClassFilterSelectionAdded);
41.  
42.             try
43.             {
44.                 if (options != null)
45.                 {
46.                     if (filter != null)
47.                     {
48.                         return ed.GetSelection(options, filter);
49.                     }
50.                     else
51.                     {
52.                         return ed.GetSelection(options);
53.                     }
54.                 }
55.                 else if (filter != null)
56.                 {
57.                     return ed.GetSelection(filter);
58.                 }
59.                 else
60.                 {
61.                     return ed.GetSelection();
62.                 }
63.             }
64.             finally
65.             {
66.                 ed.SelectionAdded -= new SelectionAddedEventHandler(ed_ClassFilterSelectionAdded);
67.             }
68.         }
69.  
70.         /// <summary>
71.         /// The allowed class PTRS
72.         /// </summary>
73.         private static ICollection<IntPtr> AllowedClassPtrs;
74.  
75.         /// <summary>
76.         /// Handles the ClassFilterSelectionAdded event of the ed control.
77.         /// </summary>
78.         /// <param name="sender">The source of the event.</param>
79.         /// <param name="e">The <see cref="SelectionAddedEventArgs"/> instance containing the event data.</param>
80.         private static void ed_ClassFilterSelectionAdded(object sender, SelectionAddedEventArgs e)
81.         {
82.             ObjectId[] ids = e.AddedObjects.GetObjectIds();
83.             for (int i = 0; i < ids.Length; i++)
84.             {
85.                 if (!AllowedClassPtrs.Contains(ids[i].ObjectClass.UnmanagedObject))
86.                     e.Remove(i);
87.             }
88.         }
89.  

[MickD]

Why is that you always find/remember the solution just after you post a question.....

I used GetEntity with PromptEntityOptions like so:

Code - C#: [Select]

1.         [CommandMethod("test")]
2.         public static void testSinglePick()
3.         {
4.             PromptEntityOptions peo = new PromptEntityOptions("Select a polyline");
5.             peo.SetRejectMessage("wrong entity type sucker!"); // must set this first!!
6.             peo.AddAllowedClass(typeof(Polyline), true);
7.  
8.             var ed = Bricscad.ApplicationServices.Application.DocumentManager.MdiActiveDocument.Editor;
9.             var promptResult = ed.GetEntity(peo);
10.             ed.WriteMessage("You selected an {0} object.\n", promptResult.ObjectId.ObjectClass.DxfName);
11.         }
12.  

Edit:
Thanks Jeff! Will soak that in as it will come in handy, cheers.

[Keith Brown]

Why is that you always find/remember the solution just after you post a question.....

Has never happened to me.