Hey all.

I am in the process of converting a pretty big 1.1 project to 2.0 and I have a couple of questions;

1. The original code uses controls as resources (build action: embedded resources) and they are loading the xaml from the Manifest Resource Stream to initiate the controls. That does still work, however it doesn't work on nested controls. ie:

If Control2 is inside Control1 it's fails when trying to XamlReader.Load (XamlParseException) Control1 to add it on a page . I recreated this with a very simple example and as far as I can see this just doesn't work anymore.

2. When using usercontrol I would like to use a base class like you can do in WPF (see this post for example: http://geekswithblogs.net/lbugnion/archive/2007/03/02/107747.aspx) but this as well gives me XamlParseException. It's kind of strange because the editor seems to support it fine. It does work if you don't do the xaml bit but then you have to manually change the *g.cs file anytime you do a change.

I can of course fix these things with workaround but it's a project with 100+ controls and I would to not have to rebuild them all. So if anyone know to fix either one of the two please let me know.

Cheers,

-Thomas-

bratta:

If Control2 is inside Control1 it's fails when trying to XamlReader.Load (XamlParseException) Control1 to add it on a page . I recreated this with a very simple example and as far as I can see this just doesn't work anymore.

That's interesting. Can you send your sample to me? My id is mchlsync AT gmail.com. I would like to take a look and will get back to you if I found the solution.

bratta:

2. When using usercontrol I would like to use a base class like you can do in WPF (see this post for example: http://geekswithblogs.net/lbugnion/archive/2007/03/02/107747.aspx) but this as well gives me XamlParseException. It's kind of strange because the editor seems to support it fine. It does work if you don't do the xaml bit but then you have to manually change the *g.cs file anytime you do a change.

I tried as below. It works for me.

1. Create SL project.
2. MyUserControlBase.cs
3. Inherits from UserControl
   
   namespace SL2Test {
       public class MyUserControlBase : UserControl {
           public string DoSomething() {
               return "Ahh! bad attemps!";
           }
       }
   }
   
   
   
4. In Page.xaml.cs
   
   namespace SL2Test {
       public partial class Page : MyUserControlBase {
           public Page() {
               InitializeComponent();
   
           }
   
       }
   }
   
   
   
5. In Page.xaml,
   
   <MyUserControlBase x:Class="SL2Test.Page"
       xmlns="http://schemas.microsoft.com/client/2007"
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
       Width="400" Height="300">
       <Canvas Width="400" Height="300" Background="Red">
       </Canvas>
   </MyUserControlBase>
   
   

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Best Regards,
Michael Sync

Blog : http://michaelsync.net
Feed : http://michaelsync.net/feed

Hey.

Thanks for your quick reply. I will give the namespace thing another try. It's 5am and I am getting quite tired so that might be why ;)

I sent you an example on the nesting resources problem.

Thanks,

-Thomas-

Re 2: You are right. That does seems to work the way you explained. However my problem is that I have my baseclasses in another namespace (in this case another assembly as well, but it doesn't matter, it errors as soon as you specify namespace).

So it's something like this:

<euc:Test1 x:Class="UserControls.Page"
xmlns=http://schemas.microsoft.com/client/2007
xmlns:x=http://schemas.microsoft.com/winfx/2006/xaml
xmlns:euc="clr-namespace:ExternalUserControl;assembly=ExternalUserControl">
...
</euc:Test1>

 Hi,

I received your mail and also replied to you. It might be something wrong with your project. I have tested with new porject. It's working fine.

You can download the sample from this link. http://michaelsync.net/demo/SL2TestNestedCtls.zip 

(If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)

Best Regards,
Michael Sync

Blog : http://michaelsync.net
Feed : http://michaelsync.net/feed

Hey again.

Yes, nesting usercontrols works fine, which is what I am doing now (just annoying having to change all the current controls). The problem arises when they are controls with a build action of "embedded resources" and you use the InitializeFromXaml to load in the XAML (please see the example I sent you).

I have made all the controls that had custom controls inside them to usercontrols to make this work. Only real problem I have now is the second one, having to manually update all the *g.cs files everytime I change a xaml file or if I do a rebuild....

Cheers,

-Thomas-

oh.  I though you are having the problem with nested controls.

bratta:

Only real problem I have now is the second one, having to manually update all the *g.cs files everytime I change a xaml file or if I do a rebuild....

You mean, you can't use like that?

<MyUserControlBase x:Class="SL2Test.Page"
    xmlns="http://schemas.microsoft.com/client/2007"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Width="400" Height="300">
    <Canvas Width="400" Height="300" Background="Red">
    </Canvas>
</MyUserControlBase>

(If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)

Best Regards,
Michael Sync

Blog : http://michaelsync.net
Feed : http://michaelsync.net/feed

Yes I can. But that limits me to use a class in the same namespace as the control. Since I have loads of controls they are divided in different namespaces and I have one class in another namespace that I want to use as the baseclass. In WPF that works by referencing the namespace with an xmlns.

Example (app is called SilverlightApplication2):

BaseClass:
namespace SilverlightApplication2.AnotherNameSpace
{
  public class Class1: UserControl
  {}
}

It works in the designer, it builds fine etc but in InitializeComponent it errors on this line:
System.Windows.Application.LoadComponent(this, new System.Uri("/SilverlightApplication2;component/Page.xaml", System.UriKind.Relative));

Error:
A first chance exception of type 'System.Windows.Markup.XamlParseException' occurred in System.Windows.dll
Additional information: AG_E_UNKNOWN_ERROR [Line: 6 Position: 95]

So it seems the application load component doesn't support that xaml syntax.

Any ideas?

Thanks,

-Thomas-

 Hi.

 If you want to use "{yourUserControl}.g.cs" for automatic binding xaml object, I don't know how it's possible.

But if you want to port a 1.1 project to 2.0, there is a simple way.

Try this.

  1. xaml file's BuildAction must be changed 'SilverlightPage'(or 'EmbededResource') to 'Resource'. 

  2. in 1.1,

         System.IO.Stream s = this.GetType().Assembly.GetManifestResourceStream("{xaml file's path in 1.1 Style}");
         _root = (Canvas)this.InitializeFromXaml(new System.IO.StreamReader(s).ReadToEnd());

     Change this part as follows. 

          System.Windows.Resources.StreamResourceInfo sri = System.Windows.Application.GetResourceStream(new System.Uri("{xaml file's path in 2.0 Style}", System.UriKind.Relative));
            string sXaml = (new System.IO.StreamReader(sri.Stream)).ReadToEnd();
            this._root  = InitializeFromXaml(sXaml) as Canvas;

   and I make a remark about 'xaml file's path'

    in 1.1 ->   '{namespace}.{filename}.xaml'

    in 2.0 -> '/{assemblyname}; component/{subdirectory}/{filename}.xaml'   

   If you change like this, you cannot use auto-generation of xaml object. So you must manually bind all xaml object to use, as you did in 1.1 alpha. 

   but you don't need to update all the *g.cs files everytime.

  I hope that this answered your question. Good luck!

Hello, there're some issues related to UserControl inheriting that we're investigating... I'm surprised to see this works:

<MyUserControlBase x:Class="SL2Test.Page"
    xmlns="http://schemas.microsoft.com/client/2007"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Width="400" Height="300">
    <Canvas Width="400" Height="300" Background="Red">
    </Canvas>
</MyUserControlBase>

Actually it shouldn't work. MyUserControlBase is not in the namespace http://schemas.microsoft.com/client/2007. This xml namespaces maps to a series of clr namespaces such as System.Windows.Controls. But there's no way it can map to your own namespace. Also this behavior is inconsistent with WPF.

This is likely to be a bug. I'll redirect this to our product team. Thanks for letting us know.

shanaolanxing - Please mark the posts as answers if they help and unmark if they don't.

Yi-Lun Luo - MSFT:

'm surprised to see this works:

:)  The solution that I found is breaking the SL rules? :) How can we add our own namespace to  http://schemas.microsoft.com/client/2007?

(If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)

Best Regards,
Michael Sync

Blog : http://michaelsync.net
Feed : http://michaelsync.net/feed

You're right. This can be a work round.

In the class library project's AssemblyInfo.cs file, add this:

[assembly: XmlnsDefinition("http://schemas.microsoft.com/client/2007", "YourNamespace")]

Now after you add reference to this assembly in your main project, you can use any classes in this namespace in your XAML files.

But without the namespace mapping, your original code should not work. So this still seems to be an issue...

shanaolanxing - Please mark the posts as answers if they help and unmark if they don't.

Guntae Park: Thanks. Though that still doesn't seems to sort my nesting problems. The only I could find to fix that was making all the 1.1 controls that had controls inside them into UserControls.

Yi-Lun Luo: That's works! It's a bit nasty but beats having to change the *.g.cs file everytime. Thanks for that!

Thanks all,

-Thomas-

bratta:

Guntae Park: Thanks. Though that still doesn't seems to sort my nesting problems. The only I could find to fix that was making all the 1.1 controls that had controls inside them into UserControls.

Sorry, Thomas. I'm a lit bit busy with using Web service and  Astoria in Silverlight. I will take a look the issue now.. I hope it should work. otherwise, Yi-Lun can help us too.

(If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)

Best Regards,
Michael Sync

Blog : http://michaelsync.net
Feed : http://michaelsync.net/feed

Hey Michael,

Thanks for that. However; I have already made my controls into usercontrol so I don't need a fix for that anymore. You might want to wait and see if anyone else have that problem before spending more time on it.

Apriciate your help.

-Thomas-

Did anyone ever find a solution to the nested controls issue?

I'm in the same situation. Had a 1.1 app, that uses nested controls, and I get XamlParseExceptions in 2.0.

Anyone fixed this?

What about Canvas? Should I use UserControl instead, as the first element in my controls' xaml file?

--
MartinHN

↑ Grab this Headline Animator

I just tested with nested control. The way that I mentioned earlier is working. Actually, the problem that we were having is not the nested control issue. The problem is about putting Base Class in different namespace.

I posted the sample in this link (http://michaelsync.net/2008/03/24/silverlight-2-beta1-user-control-inheritance) but I didn't put the base control in different namespace. If you want this, please change as below based on the sample from the link above.

1. Change BaseControl.cs

namespace SL2Controls.Anothernamespace {
    public class BaseControl : UserControl {

    }
}
 

2. update assemblyinfo

[assembly: XmlnsDefinition("http://schemas.microsoft.com/client/2007", "SL2Controls.Anothernamespace")]

3. Update InheritedControl.xaml.cs

public partial class InheritedControl : SL2Controls.Anothernamespace.BaseControl {
        public InheritedControl() {
            InitializeComponent();
        }
    }

OR

Add using SL2Controls.Anothernamespace; 

4.  Update InheritedControl.g.cs

 public partial class InheritedControl : SL2Controls.Anothernamespace.BaseControl {

OR

using SL2Controls.Anothernamespace; 

Updating the generated file is suck but we have no other way to do that.  If you run the sample, you will see it works. if you edit the XAML file, you won't need to modify the generated file. It's strange thing.

(If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)

Best Regards,
Michael Sync

Blog : http://michaelsync.net
Feed : http://michaelsync.net/feed

There is a workaround if you want to inherit from a "BaseControl" class in another namespace without having to update the generated ".g.cs" file.  This hack is to include the base control's namespace in a resource.  This works because the autogenerated file adds a "using" statement for any namespace referenced in the Resources.

To apply this workaround, use Michael's steps #1, #2, and #3 (from the previous post). Instead of editing the generated file (step #4), add a reference to the clr-namespace, and then use this namespace in the Resources. 

1. <BaseControl x:Class="SL2Controls.InheritedControl"  
2. xmlns="http://schemas.microsoft.com/client/2007"  
3. xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"  
4. Width="400" Height="300"
5. xmlns:basecontrol="clr-namespace:SL2Controls.Anothernamespace"  
6. > 
7. <BaseControl.Resources>
8. <basecontrol:anyclass x:Name="anyname" />
9. </BaseControl.Resources>

Steve Nyholm "snyhol"
blog: http://www.AListForEverything.com