UpdateSourceTrigger / Silverlight - silverlight-4.0

In the MSDN documentation, it documents that you can set the UpdateSourceTrigger to an event of your choosing...
MSDN UpdateSourceTrigger Documentation
I can't seem to get this to work in Silverlight, as it is seems to want either Explicit or Default...
If this is only for WPF - how can you tell from the documentation that Silverlight is excluded?

The UpdateSourceTrigger is not an event, but an enumeration.
See http://msdn.microsoft.com/en-us/library/system.windows.data.updatesourcetrigger.aspx
So, what you are seeing are the choices available to Silverlight.

Silverlight 5 adds support for PropertyChanged for UpdateSourceTrigger. You can find an example here.

Related

Page Navigation in Windows 8 XAML (without using code behind)

For my windows 8 application i am trying to navigate between pages with out using code behind.
For example, i have one image in my UI without creating tapped event for that image i need to navigate to another page,
<Image Source="ms-appx:///Assets/Logo.png" Width="155" Height="110" Tapped="{ // Navigation method here }"/>
Is it possible to navigate between pages like this...? If possible, how can i get this to work??
XAML is just a declarative language without action part so code behind is an essential part of it.
All interactions work via events and event can be handled in a code behind only. So what you want is not possible with XAML(at least with WinRT XAML).
If you are asking if you can specify the code inside the .xaml file, then no, that is not possible.
If you are asking if you can avoid adding code to the .xaml.cs file, then yes, that is possible. You will still need to specify a method but it can even be done as a simple lambda. You will need to use the Command hooks rather than the Event Hooks, e.g.
<Button Command="{Binding GoConnectionCommand}" ... />
The code for this command is usually defined in the ViewModel as part of the MVVM pattern, and Josh Smith explains it far better than I will.
AlSki mentioned using a ViewModel. Although technically the ViewModel is not part of the "code behind" for the XAML file, it's still code and I believe you were asking for a no code solution.
ixSci is correct that there is no way to do this out of the box without code behind in WinRT XAML.
In full WPF it's possible to do this using a behavior called NavigateToScreenAction. You can read about it here. Unfortunately behaviors don't ship out of the box with WinRT, but they can be added back in by an open source project called WinRtBehaviors.
There is no NavigateToScreenAction behavior for WinRT, but one could be created. There is a good article on creating behaviors with the library here. It will obviously require code to create the behavior, but after it's created you could use it in XAML without any code.
Really, the short answer is it's not possible to navigate without code on WinRT.
Dev support, design support and more awesome goodness on the way: http://bit.ly/winappsupport

Metro equivalent for HeaderedItemsControl

Converting a WPF application from .Net 4.0 to Metro.
It uses HeaderedItemsControl in various places.
I have not been able to find that control or a replacement candidate in Metro (Windows.UI.Xaml namespace)
So what is the recommended control in Metro to provide the functionality of HeaderedItemsControl?
You could easily create one by deriving from ItemsControl and adding a few simple dependency properties. You can see which properties are present in the WPF version here. You might not need all of them, but from a quick glance I can see a Header property which is just an object type. You would put a ContentPresenter in your HeaderedItemsControl's ControlTemplate and bind its Content to the HeaderProperty using TemplateBinding. Then bind the HeaderTemplate to the ContentTemplate of the ContentPresenter, etc.
Not sure how useful it is though to port WPF XAML code directly to WinRT. You're just asking for trouble in terms of code compatibility, but also porting a likely desktop-designed UI to a more touch-centric world.

How to add an Array in WinRT XAML

I am looking to declare an array in XAML. I can do this in WPF. Just can't seem to find the right namespace in WinRT. Anyone know?
<Page xmlns:list="?Something?">
<Page.Resources>
<x:Int32 x:Name="MyScalarValue">123</x:Int32>
<list:Array x:Name="MyValueList">
<x:Int32>123</x:Int32>
<x:Int32>456</x:Int32>
<list:Array>
</Page.Resources>
</Page>
x:Array (and x:Static and a few other ones) aren't presently supported in WinRT. For that matter, x:Array isn't supported in Silverlight either, despite developers pushing for it.
Given the fact that the XAML implementation for WinRT appears to be more closely aligned with SL than WPF, this isn't too surprising.
Edit - some more info regarding SL4+ vs. WPF differences:
"Notable omissions here that exist in WPF or [MS-XAML] are x:Array, x:Code, x:Type, and code access modifiers."
Also, a delta between SL4 and the WinRT implementation here, and its associated links, makes it clear that these bits didn't magically make it into WinRT when they were (and still are) omitted from SL.

How do I make a property mandatory on a custom user control?

I have a custom control and would like the properties to be mandatory (not default) when a programmer codes the control. Is there a good way to do this without throwing exceptions in the program?
I think you should pass the mandatory fields in constructor define only 'get' property against it.
That's what Jon Skeet the great says about it here :)
I decided to use a smart-tag panel using a custom designer. Maybe this will help someone else...
http://msdn.microsoft.com/en-us/library/ms171829.aspx

WinRT XAML apps + missing [XmlnsDefinition] attribute

There is not [XmlnsDefinition] attribute in XAML metro style applications, based on WinRT.
How my custom namespace mappings from WPF/SL apps should be migrated to WinRT XAML apps?
Looks like XmlnsDefinitionAttribute is missing. There is XmlnsDefinition struct but that is of not much use since there is no way to use it to set custom namespace mappings.
A discussion at https://social.msdn.microsoft.com/Forums/windowsapps/en-US/026baea0-6324-46ee-956a-72dbb4c90ca1/xmlnsdefinition-replacement-in-winrt?prof=required says:
there is no analogous attribute.
You might be able to provide similar data in a custom
IXamlMetadataProvider implementation, but since that is automatically
generated for you I'm not sure it can be overridden.