When I reference a control library Visual Studio does not enable me to drag CompositeControl descendants onto the WebPage as the control is hidden/disabled depending on the whether I show all controls.

If I change the descendant to be of type WebControl and change the class name and recompile it appears fine. If I then change it back to descend from CompositeControl and keep the class name Visual Studio still keeps the icon and lets me drag it onto the web page.

In all cases I can manually cobble together the tags to show it and visual studio will render the control, allow me to modify properties etc.

This behavior seems very unusual to me especially since several of the new controls like Login, ChangePassword, SiteMapPath, and Wizard descend from CompositeControl. Is this expected behavior and if so, why? This seems like a bug to me.

Hi,

do you have small sample of such control for a repro?

You are just inheriting from it, have you added or modified anything else?

It is easy to reproduce:

1. Create a new web site project.
2. Right click in the solution explorer on the top-most node (Solution <solution-name>) and Add New Project.
3. Select Class Library.
4. Add Reference to the new class library and include System.Web.
5. Modify Class1.cs to be as follows:
using System;
using System.Collections.Generic;
using System.Text;
using System.Web.UI.WebControls;

namespace ClassLibrary1
{
    public class Class1 : WebControl
    {
    }

    public class Class2 : CompositeControl
    {
    }
}
6. Build the solution and switch over to Default.aspx in Design view. Note that Class1 is now available but Class2 is not.

This is a known bug in Whidbey when automatically creating such toolbox items derived from a base abstract class.  A workaround for now would be to explicitly add/pick these controls using the "Choose Toolbox Items" dialog.

Thanks!    - Ibrahim

I'm having trouble with the "Add/Pick" workaround.  My control shows as disabled.  When I right click on the toolbox, press choose items,  find my control (which is checked but shows as greyed out on the toolbox), press OK, nothing shows up on my default.aspx page and the control still shows as greyed out on the toolbox.

Please explain this workaround in more detail or point me to the bug report with the details. 

For me, composite controls sometimes show up, and other times they do not.  I don't understand what causes the apparent randomness.  This problem is very frustrating.

I am having this same problem - some of my custom server controls will not appear in the toolbox, and some of those that do appear will not actually work (as in, they cannot be dragged onto an aspx page).

I think this has to do with the type of base class that I am inheriting from. I'm extending some of the Telerik controls, and those that inherit from their controls that do not inherit directly from a stock asp.net control suffer this same problem.

A workaround would be welcomed as this is a prety serious problem for me.

 

I think I just solved this problem - try changing the class declaration from

 

   class foo : base { ... }

to

   public class foo : base { ... }

 

doesn't help me I don't think.  This is what my declaration looks like. I was hoping to hear from the Microsoft person ( ibrahimm ) who is on this thread also.  I'm about to post a blog entry with a very nice CAPTCHA control I wrote but I'm nervous I will get bombarded with people saying it doesn't work.  All Microsoft's controls seem to work, why not mine?

 [Designer(typeof(TemplateControlDesigner))]
    [ParseChildren(true)]
    [PersistChildren(false)]
    [DefaultProperty("Title")]
    [DefaultEvent("OnVerified")]
    [ToolboxBitmap(typeof(PeterKellner.Utils.CaptchaUltimateControl), "toolbaricon.bmp")]
    [ToolboxData("<{0}:CaptchaUltimateControl runat=server></{0}:CaptchaUltimateControl>")]
    public class CaptchaUltimateControl : CompositeControl
    {
    
ibrahimm?  Help please.

pkellner:

ibrahimm?  Help please.

Any help yet?  Just running into this same issue myself now...looking for help...?

I'm also stumped by this....

I was following the example in:

http://msdn2.microsoft.com/en-us/library/ms379565.aspx

 

I'm also experiencing this problem, and followed the tutorial JGriffiths linked to - could someone please help with this problem??

 

hello, has anyone found a solution to this problem?

i tried creating a custom composite control but instead of inheriting it from 'CompositeControl' class, i used 'WebControl' class and 'INamingContainer' interface. after building the code, my custom composite control started to appear in the VS2005 SP1 toolbox.
 

public class MyCompositeControl : WebControl, INamingContainer
{

// some code here...

}
 

I think SP1 fixed a lot of these issues. If I have the project with web controls in it, in the solution, they often appear like they should. However, if I just reference the dll file, the problem is still there, and I haven't found a way around that.

i'm not really sure what you mean by SP1 has fixed a lot of these issues coz i have SP1 installed but the problem still persists. so, in building my custom composite control i didn't inherit from CompositeControl class but instead inherited from 'WebControls' and 'INamingContainer'. By doing this, my custom composite control appears in the toolbox.

I mean that I had less of a problem once SP1 was installed, and that if you inherit from e.g. CompositeControl, have the project in your solution and go to design view it should appear in the toolbox. Glad you solved it another way though.