XAML extension question

[Lloyd Dupont]

In my application I want to display some data in a list box.
I need to display the data as a picture.

My 1st idea was to create a ValueConverter to convert my datas to
ImageSource
But this has a few problem, the biggest one is there is no parameter!
So I though of MarkupExtension
something like that:
<ListBox ItemsSource={Bi nding Document.Maps}>
<ItemTemplate >
<Image Source="{local: Map2Image PreviewDpi=24, Background=fals e}" />
</ItemTemplate>
</ListBox>

but here, problem, in the Map2ImageExtens ion.ProvideValu e(IServiceProvi der)
I don't ave the current data, worst, I have no idea to get it.

I was able to get the IProvideValueTa rget but it only knows about the
"Image" object, not about the current item.
I tried to look into the "Binding" and "BindingBas e" code with reflector,
but I don't understand what's going on...
Any tip?


Otherwise I could write a specialized viewer FrameworkElemen t, but I though
of using MarkupExtension might be a nice way to solve the problem....

[=?Utf-8?B?SG9yc3QgS2xlaW4=?=]

RE: XAML extension question

Hi Lloyd


I don't have an answer to your problem. Sorry.
But today I have the same problem and don't know how to get the instance of
the ServiceProvider .

In my case I want get the "ObjectDataProv ider"
How can tell us how we can get our ServiceObjects?


My Xaml:

<ObjectDataProv ider x:Key="VitoPati ent" ObjectType="{x: Type
VFC:GetDataComm and}" MethodName="Exe cute">
.....

<StackPanel VFW:DesignView. DataContext="{B inding
Source={VFW:MyD ynamicResource VitoPatient},
Path=ParentObje cts[Person__Patient]}">
.....

My Class:

<MarkupExtensio nReturnType(Get Type(Object)),
TypeConverter(G etType(DynamicR esourceExtensio nConverter))_
Public Class MyDynamicResour ce
Inherits System.Windows. DynamicResource Extension

Public Overrides Function ProvideValue(By Val serviceProvider As
System.IService Provider) As Object
If (Not VitoResourceMan ager.DesignMode ) Then
If (GetType(Object DataProvider).I sInstanceOfType (serviceProvide r))
Then
Return MyBase.ProvideV alue(servicePro vider)
Else
Return MyBase.ProvideV alue(servicePro vider)
End If
Else
Return VitoApplication .FindDynamicRes ource(Me.Resour ceKey.ToString)
End If
End Function

Public Sub New()
MyBase.New()
End Sub

Public Sub New(ByVal resourceKey As Object)
MyBase.New(reso urceKey)
End Sub

End Class

[Lloyd Dupont]

Re: XAML extension question

Hi,

--

Hi Lloyd
>
>
I don't have an answer to your problem. Sorry.
But today I have the same problem and don't know how to get the instance
of
the ServiceProvider .
>
In my case I want get the "ObjectDataProv ider"
How can tell us how we can get our ServiceObjects?
>
>

when I read you VB code it looks a bit strange to me... :-/
anyway here is pseudo C# code (i.e. from the top of my head) to lookup for
object by name (define before the object using this markp extension, same
restriction as in StaticResource)

class MyMarkup : MarkupExtension
{
public object ProvideValue(IS erviceProvider sp)
{
if(sp == null)
return null
IProvideValueTa rget pvt =
(IProvideValueT arget)sp.GetSer vice(typeof(IPr ovideValueTarge t));
if(pvt == null)
return null;
FrameworkElemen t fe = pvt.Target as FrameworkElemen t;
if(fe == null)
return null;

DependencyObjec t do = fr.FindName("aN ame");
// ... whatever you need to ...
}
}

[=?Utf-8?B?SG9yc3QgS2xlaW4=?=]

Re: XAML extension question

Hi Lloyd

Thanks a lot that looks good to get the TargetObjetct.

But How can I get the Source?

In my case the
<ObjectDataProv ider x:Key="VitoPati ent" ObjectType="{x: Type
VFC:GetDataComm and}" MethodName="Exe cute">

Best regards Horst

[Lloyd Dupont]

Re: XAML extension question

mmhh... I don't understand the question?..
what is this source you talk about?

anyway your only hope is a FindName() (or FindResource()) call to get other
object on the UI.
Binding use an internal Expression class which sets up event listener and
can


"Horst Klein" <HorstKlein@dis cussions.micros oft.comwrote in message
news:47CB3366-391E-462B-A550-BE9D978813DC@mi crosoft.com...

Hi Lloyd
>
Thanks a lot that looks good to get the TargetObjetct.
>
But How can I get the Source?
>
In my case the
<ObjectDataProv ider x:Key="VitoPati ent" ObjectType="{x: Type
VFC:GetDataComm and}" MethodName="Exe cute">
>
Best regards Horst